MRI Boards

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The stalk of the pituitary gland is also known as the: A. Infundibulum B. Basil ganglia C. Cauda equina D. Hilum

A; A small outgrowth of the ventral wall of the embryo brain from which the pars nervosa (the posterior lobe) of the pituitary gland develops is also called the infundibulum. (Another name for this structure is the pituitary stalk.)

Relaxation time

After excitation the longitudinal magnetization returns toward equilibrium with a time constant T1 and the transverse magnetization decays toward zero with a time constant T2

Fast Fourier Transformation(FFT)

Algorithm for fast reconstruction of raw data into an MR image

Inflow technique

Also referred to as Time of Flight (TOF) MR angiography

Fat Saturation

An MR technique used to suppress signal from fat protons, yielding a "water only" image, utilizing a chemically selective presaturation pulse

Spin echo

An MRI pulse sequence whose signal is an echo resulting from the refocusing of magnetization after the application of 90o and 180o RF pulses

Phase

An angular relationship describing the degree of synchronism between sinusoidal waveforms of the same frequency

Phantom

An artificial object that can be imaged to test the performance and quality of a magnetic resonance system

Oblique

An imaging technique which produces images along planes that are not perpendicular to the X,Y, or Z axes

How do you produce an oblique slice with gradients

Apply two gradients at the same time. EX: coronal and sagittal will give you an oblique

The echo time is the A. Time between the 180º inverting pulse and the 90º RF excitation pulse B. Time between the 90º RF pulse and the peak of the signal in the receiver coil C. Time it takes for the flip angle to reach the Ernst angle of peak signal D. Time between two 90º RF pulses

The effect by which a patient may experience a visual stimulation, described as "seeing stars", is known as: A. Magnetic personality effect B. Magnetophosphenes C. Magneto-dynamic effect D. Magnet dynamic contrast susceptibility effect

The energy used to form MRI images is ____________ the patient's tissues. A. Attenuated by B. Emitted from C. Amplified from D. Reflected off

The first major branch of the abdominal aorta is the celiac trunk, which branches into the ________ arteries. A. Renal, mesenteric and iliac B. Gastric, hepatic and splenic C. Pulmonary, portal and gastric D. Hepatic, mesenteric and iliac

The general public is limited to a magnetic field of ___________? A. 1 Gauss B. 5 Gauss C. 10 Gauss D. 1 Tesla

The general public is limited to a magnetic field of: A. 1 Gauss B. 5 Gauss C. 10 Gauss D. 1 Tesla

The individual nerve roots that leave the lower portion of the spinal cord and progress downward are termed the __________ or "horse's tail." A. Equestrenoma B. Cauda equina C. Cervico-medullary junction D. Supraspinal ligament

The net magnetization vector (NMV), when aligned with the magnetic field direction, is aligned __________. A. Along the transverse axis B. Along the longitudinal axis C. 90º perpendicular to the direction of the magnetic field D. Both A & C

The optimal imaging plane for evaluation of the degree of curvature due to scoliosis would be: A. Axial B. Coronal C. Sagittal D. Weight bearing

The optimal imaging plane to demonstrate the carpal bones and the interosseous ligaments would be: A. Axial B. Coronal C. Sagittal D. None of the above

The optimal technique to visualize the circle of willis would be: A. 2D TOF B. 3D TOF C. 2D PCA D. 3D PCA

The patient image display with sequence parameter visualization is located in the _________. A. Equipment room B. Scan control room C. Magnet room D. Green room

The percentage of patients reported to have reactions to gadolinium MRI contrast are: A. None B. Less than 1% C. 10% D. 42.57%

The pixel size of the images which result from a 3D acquisition using a 240mm FOV, a 272 x 272 matrix, 32 slices and a volume of 64 mm is: A. 0.56 x 0.56 mm B. 0.88 x 0.88 mm C. 1.12 x 1.12 mm D. 1.58 x 1.58 mm

The protons that align themselves with the direction of the static magnetic field (B0) exist in a ___________energy state than those anti-parallel to the magnetic field. A. Aliased B. Lower C. Higher D. Chemical Shifted

The pulse sequence that should be utilized the least in a patient with implanted metallic hardware is: A. Spin echo B. Gradient echo C. Inversion recovery D. Fast spin echo

The vertebral body will display a _________ signal intensity on T1 weighted images in the presence of fracture, infection or neoplasm. A. Hyperintense B. Hypointense C. Isointense D. None of the above

Two gradients applied at the same time during slice selection are utilized for: A. Reducing the cryogen boil off rate B. Encoding oblique slice planes C. Eliminating residual transverse magnetization for steady state D. Encoding 3D volumes for MRA

What effect would decreasing the FOV have on the spatial resolution of an image? A. None B. Increase C. Decrease D. K space filled faster

What effect would using a steep slice select slope and/or narrow bandwidth have on slice thickness? A. Partial volume averaging will occur B. Slices will be thin C. Slices will be thick D. Slices will cross-talk

What is a fast spin echo? A. 90° RF followed by 180° RF B. 90° RF followed by train of 180° RF pulses C. 180° RF followed by 90°RF D. variable° RF followed by gradient to produce echo

What is the TR range for a Proton density contrast weighted image ? A 350-700ms B. 1600- 4000ms C. 2000- 6000ms D 80 - 120ms

What type of magnet is used with most MRI systems currently manufactured? A. Resistive B. Superconducting C. Permanent D. Refrigerator

What type of magnet is used with most systems currently manufactured? A. Permanent B. Superconducting C. Resistive D. Upright

What would be the most useful sequence for evaluation of an acute stroke? A. Inversion recovery B. Diffusion weighted sequence C. Spin echo T2 D. Fat suppressed T1

When gradient moment nulling is used as an imaging option in MR sequences: A. SNR is degraded B. The minimum TE is increased C. The minimum TE is decreased D. More slices are available per TR

When imaging the female pelvis, the plane best suited for uterine anatomy would be: A. Axial B. Sagittal C. Coronal D. None of the above

When imaging the wrist, the optimal plane to visualize the carpal tunnel is: A. Sagittal B. Axial C. Coronal D. FAI oblique parallel to femoral neck

When moving blood enters a magnetic field, an effect on the ECG seen as a "T wave swelling" or spike occurs, also known as: A. Hypertensive effect B. Magnetohydrodynamic effect C. Dynamothoracic effect D. Dynamometer

When positioning a patient for a shoulder MRI, the patient should be centered at what anatomic landmark? A. Coronoid process B. Coracoid process C. Scapular wing D. Biceps tendon distal insertion

Which RF pulse is always absent in a gradient echo sequence? A. 90° excitation pulse B. 180° refocusing pulse C. Presaturation pulse D. Flip angle pulse

Which RF pulse refocuses a decaying spin echo? A. 90° B. 180° C. 67° D. 30°

Which dural venous sinuses drain from the confluence of sinuses (by the internal occipital protuberance) to the mastoid portion of the temporal? A. Superior sagittal sinus B. Transverse sinuses C. Ethmoid sinuses D. Sigmoid sinuses

Which factors controls the amount of T2 weighting in an image? A. TR B. TE C. Flip angle D. NEX

Which fissure divides the frontal and parietal lobes from the temporal lobes? A. Salty fissure B. Sylvian fissure C. Anterior fissure D. Longitudinal fissure

Which of the following is NOT affected by changing the slice thickness? A. The signal-to-noise ratio of the image B. The T1 contrast C. The image resolution D. The anatomical coverage

Which parameter will provide the better spatial resolution? A. 4mm slice thickness; 256 x 192 matrix B. 4mm slice thickness; 256 x 256 matrix C. 6mm slice thickness; 256 x 192 matrix D. 6mm slice thickness; 256 x 256 matrix

Which spinal ligament is vertically oriented, connecting the dorsal tips of the spinous processes? A. Ligamentum flavum B. Supraspinous ligament C. Interspinous ligament D. Intertransverse ligament

_______ may be defined as a personal injury; or as "a civil action other than a breach of contract." A. Res Ipsa Loquitur B. Tort C. Respondeat superior D. Statutory law

________ and _________ won the Nobel Prize in 1952 for their invention of equipment which could measure the magnetic resonance in solids and fluids. A. Lauterbur; Mansfield B. Bloch; Purcell C. Bloch; Maxwell D. Larmor; Fourier E. Faraday; Rabi

_________ is a file on the computer where the collected echoes are stored prior to being processed into an image by the Fourier Transform. A. Analog to digital converter B. Raw data C. K-space D. A gradient

____________ can be described as water molecules moving the same way in every direction. A. Anisotropic diffusion B. Isotropic diffusion C. Anisotropic voxel D. Isotropic voxel

_____________ is a tort doctrine that states employers are responsible for the actions of their employees. A. Liability B. Respondeat superior C. Res ipsa loquitur D. HIPAA

Calculate the voxel volume for the following pulse sequence parameters: TR 450, TE 20, FOV 24cm, 320 x 320 matrix, 3mm slice thickness. A. 0.75mm3 B. 1.69mm3 C. 1.75mm3 D. 2.25mm3

B FOV x 10 to make MM; FOV/ phase matrix X FOV/ freq matrix x slice thickness 24x 10= 240 240/ 320(0.75) x 240/320(.75) x 3 = 1.687

Calculate the pixel area for the following sequence: TR 4000, TE 120, FOV 28cm, 304 x 304 matrix, 2 NEX, ETL 12. A. 0.76 mm2 B. 0.85 mm2 C. 0.92 mm2 D. 1.84 mm2

B FOV/ matrix x FOV/matrix =pixel area 280/304 x 280/304 = .85

The scan time of a fast spin echo sequence utilizing a TR of 3500ms, a TE of 90ms, a 256x256 matrix, 1NSA, a 220mm FOV and an echo train length of 5 is ______ minutes, approximately. A. 2 B. 3 C. 8 D. 11

B TR x phase Matrix x NEX / ETL / 1000 3500 x 256 x 1 / 5 = 179,200 / 1000= 179.2 sec= 2.98 min

On T2 weighted images of the spine, the CSF (cerebrospinal fluid) appears: A. Isointense to the spinal cord B. Hyperintense to the spinal cord C. Hypointense to the spinal cord D. None of the above

B hyperintense= high signal

Calculate the scan time for a spin echo sequence with the following parameters: TR 450, TE 20, 224 x 256 matrix, 3 NSA, 4mm slice thickness. A. 1 min 16 sec B. 5 min 2 sec C. 5 min 4 sec D. 5 min 46 sec

B; TR x Phase Matrix x NEX / 1000 to get into seconds

Calculate the scan time for a spin echo sequence with the following parameters: TR 400, TE 25, 192 x 256 matrix, 2 NSA, 3mm slice thickness. A. 2 min 24 sec B. 2 min 34 sec C. 2 min 56 sec D. 3 min 6 sec E. 3 min 34 sec

B; TR x Phase matrix X NEX / 1000

Calculate the scan time for a fast spin echo sequence with the following parameters: FOV 16cm, TR 2500, TE 90, 208 x 256 matrix, 6 NEX, 5 mm slice thickness, 18 ETL. A. 2 min 24 sec B. 2 min 53 sec C. 2 min 56 sec D. 3 min 6 sec E. 3 min 34 sec

B; TR x Phase matrix X NEX/ ETL / 1000

The insular cortex is primarily responsible for: A. Speech B. Motor control; cognitive function C. Auditory response D. Insulating the white matter

B; The insulae play a role in diverse functions usually linked to emotion or the regulation of the body's homeostasis. These functions include perception, motor control, self-awareness, cognitive functioning, and interpersonal experience.

If the NEX is increased from 2 to 6, the signal-to-noise ratio increase would be: A. 1.4 B. 1.7 C. 2 D. 4

B; square root of the % increase.

A prescription requesting an MRI to evaluate an islet cell tumor would indicate a study of the ________? A. Internal auditory canals B. Mediastinum C. Pancreas D. Talus of the ankle

A reduction in FOV will result in: A. Decrease in spatial resolution B. Increase in SNR C. Decrease in SNR D. None of the above E. A and C only

Adequate patient care dictates a patient having an MRI should be __________ monitored. A. EtCO2 (End-Tidal CO2) B. PG (peripheral gating) C. Visually and/or verbally D. Not at all

All of the following are TRUE except: A. Excitation is the process of moving the net magnetization away from the Z axis B. Magnetic field gradients are static C. The RF field oscillates at the Faraday frequency D. The resonance frequency in a 1.5 Tesla magnet is 63.86 Mhz

All of the following are non-ferrous substances EXCEPT: A. Plastic B. Titanium C. Iron D. Copper

All of the following are true mechanisms of saturation EXCEPT: A. A saturation pulse excites hydrogen protons to a frequency that gives no signal on the image B. Partial saturation yields T1 weighting; occurs when NMV >90° C. Partial saturation yields T1 weighting; occurs when NMV is 180° D. Full saturation suppresses longitudinal magnetization; occurs when NMV is 180°

All of the following are true regarding gadolinium EXCEPT: A. Gadolinium chelates do not pass normal blood-brain barrier B. Gadolinium is not FDA approved for whole body MRA C. Gadolinium has six unpaired electrons D. Gadolinium chelates do pass a disrupted blood-brain barrier

An aortic arch root aneurysm is located: A. In the external iliac artery B. Directly proximal to the common carotid bifurcation C. In the ascending segment of the thoracic aorta D. Proximal to the bifurcation of the abdominal aorta

An increase in TR will produce all of the following EXCEPT: A. Increase the signal-to-noise ratio B. Decrease T1 weighting C. Decrease the number of available slices D. Increase scan time

Choose the correct slice thickness to create an isotropic voxel for the following: TR 2000, TE 90, Matrix 256 x 256, FOV 32cm. A. 0.75 mm B. 1.25 mm C. 2.00 mm D. 2.50 mm

Consistent room temperature of 65-75°F, humidity of 50-70%, and sufficient air flow in the MR scan room is recommended to: A. Reduce the cryogen boil off rate B. Minimize the risk of local surface coil burns C. Make patients less vulnerable to the RF heating effects D. Keep the shim and gradient coils from overheating

Decreasing the receiver bandwidth (narrow rBW): A. Increases the contrast based on T1 tissue relaxation times B. Decreases the SNR of the image C. Increases the SNR of the image D. Inverts the SNR of the image E. Does not affect the SNR of the image

Doubling the magnetic field strength will: A. Increase the SNR factor by half B. Decrease the SNR factor by half C. Yield an increase of double the SNR D. Yield a decrease of double the SNR

During a post surgical MRI of the lumbar spine, the evaluation of post operative surgical regions and/or the possibility of scar tissue can be best accomplished by: A. Axial slice plane; T1 weighted post gadolinium B. Axial slice plane; T2 weighted post gadolinium C. Sagittal slice plane; T1 weighted post gadolinium D. Sagittal slice plane; T2 weighted post gadolinium

FSE is an abbreviation for: A. Fractional spin excitation B. Fourier sampling echo C. Fast spin echo D. Fast sampling excitation

For a given number of slices, which of the following pulse sequences uses the most 180° RF pulses during each TR period? A. Spin echo B. Gradient echo C. Dual contrast spin echo D. Inversion recovery

For patients that have undergone surgery for herniated disc in the lumbar spine, gadolinium contrast enhancement can be utilized to distinguish recurrent disc from post-operative scar tissue because: A. Post-operative scar does not enhance; recurrent disc enhances B. Post-operative scar enhances; recurrent disc does not enhance C. Disc enhances more slowly than post-operative scar D. Neither disc nor post-operative scar enhance

Gradient moment nulling is used to compensate for: I. First order motion II. Second order motion III. Slow flowing vessels IV. Fast flowing vessels A. I and II B. I, II and III C. I and III D. I and IV E. I, II, III and IV

How many cranial nerves are there? A. 6 B. 9 C. 12 D. 15

IV Gadolinium contrast administration is indicated for: A. MRCP B. MRA of the renal arteries C. Central nervous system D. A & C only

If a brain exam is being perfomed and the request is made to rule out microadenoma due to elevated prolactin levels, a protocol with thin cuts through the ____________ should be performed. A. Internal Auditory Canals B. Orbits/Optic nerves C. Pituitary gland D. VII and VIII Cranial Nerves

If a brain exam is being performed and the request is made to rule out acoustic neuroma, a protocol with thin cuts through the _________ should be performed. A. Pituitary gland B. Orbits/Optic nerves C. Internal Auditory Canals D. Thyroid Gland

If a transverse/axial slice plane has been selected, the __________ is enabled to alter the magnetic field around the patient's body. A. X gradient B. Y gradient C. Z gradient D. Shim coils

If the maximum slices in a set TR is 10, and the necessary number of slices for a given sequence's anatomical coverage is 26, how many acquisitions (packages) will be required? A. 1 B. 2 C. 3 D. 4

If the radiologist requires 3mm slices axially acquired through the IAC, with a slice gap of 0.5mm, and requires 4.2cm total coverage, how many slices must be selected? A. 6 B. 9 C. 12 D. 15

If the third ventricle is dilated, but the fourth ventricle is not, there would then be pathology associated with: A. Insular cortex B. Basal ganglia C. Aqueduct of Sylvius D. Lateral ventricles

Immediately following the application of the 90° RF pulse, the transverse magnetization is: A. Eliminated B. The same as longitudinal magnetization C. Non-zero D. Zero

In _____, Damadian and his team constructed the first super conducting NMR scanner and produced the first image of the human thorax, which took almost 5 hours to scan A. 1946 B. 1952 C. 1977 D. 1981

In a dual contrast spin echo sequence with echo times of 25ms and 90ms, the second echo image has __________ than the first echo image I. more T2 contrast II. lower signal-to-noise ratio III. more T1 contrast A. I only B. III only C. I & II only D. I & III only

In a spin echo pulse sequence, an echo is produced from: A. Flip angle B. A gradient C. A combination of two or more RF pulses D. A 90º RF pulse

In a spin echo sequence, the time between the 90° RF pulse and the 180° RF pulse is known as the: A. TR B. TE C. 1/2 TE D. TI E. Double Echo

In order to acquire an extracranial time-of-flight arterial MRA, a presaturation pulse would be applied in which location to saturate unwanted blood flow? A. Superior to slice group, inferior to cardiac margin B. Inferior to slice group, inferior to brain stem C. Superior to slice group, superior to brain stem D. Inferior to slice group, proximal to carotid bifurcation

In the 1930's- _______________ detected and measured single states of rotation of atoms and molecules, determining the magnetic moments of the nuclei A. Felix Bloch B. Richard Ernst C. Isidor Isaac Rabi D. Sir Joseph Larmor

In the year ______, Schering's _________ IV Gadolinium contrast gets the first approval by the FDA A. 1977; Indomitable B. 1981; Iodinatable C. 1988; Magnevist D. 1991; RARE

In which of the following pulse sequences would you expect to find the shortest TR? A. Fast spin echo B. Inversion recovery C. Gradient echo D. Spin echo

Lengthening TR with a short TE in a spin echo sequence will: A. Increase T2 weighting B. Increase T1 weighting C. Increase proton density weighting D. Increase inversion time to null signal from fat

Long TR and Short TE exhibit which type of contrast A. T1 B T2 C Proton Density D IR

On an image of the thoracic spine in the sagittal plane, utilizing a 28cm FOV, the vertebral disc levels can be determined by: A. Using small dipole magnets to move isocenter to the spine B. Using the sternal notch as a landmark and counting from T1 C. Using a large FOV localizer and optional vit E markers to count down from C2 D. Using lead mammo markers over the xiphoid

Patient screening in the MR environment should occur ________. A. When the patient fills out most of the questionnaire B. For most patients C. More than once, by trained professional(s) D. For adults only

Patients with suspected intra-ocular metallic foreign bodies must be screened for metal prior to entering the MR scan room. This can be accomplished by: A. Waving a horseshoe magnet over the retina B. Covering one eye at a time and reading a letter chart from 10 feet distance C. Taking Xrays of the orbital region and obtaining documented radiologist clearance D. Wearing lead lined glasses during the procedure

Patients with tattooed eyeliner or other ferrous pigment eye region cosmetics should be advised of what possible complication during the MR exam? A. Temporary discoloration of the eyeliner/makeup B. Permanent dislodgement of the tattooed area C. Temporary skin irritation or swelling of the eyes or surrounding tissues D. Temporary discoloration of eye pigment irregardless of the presence of contact lenses

Phase contrast MRA techniques produce images in which the signal intensity within the vessel is dependent upon the: A. Field of view selected B. The T1 time of the tissue C. Velocity of the flowing blood D. Larmor frequency of arterial versus venous blood

RF heating is more of a concern in ________ sequences. A. Gradient echo B. Inversion recovery C. Fast spin echo D. Time of flight

Reducing the TE: A. Increases the contrast based on T1 tissue relaxation times B. Reduces saturation effects C. Decreases the contrast based on T2 tissue relaxation times D. Increases fat suppression E. Increases signal from fluids

Regions of the body that do not quickly dissipate thermal absorption from SAR during MR procedures are: A. Head and neck B. Liver and kidneys C. Eyes and testicles D. Spine and sacrum E. All of the above

TR is short for: A. Time to Repeat (scans) B. T1 Recovery C. Repetetion time D. T2 Rephasing

The __________ is the soft, jelly-like, inner portion of the intervertebral disc. A. Conus medullaris B. Cauda equina C. Nucleus pulposus D. Annulus fibrosus

The __________ is the spinal region that is LEAST affected by cerebrospinal fluid (CSF) pulsation. A. Cervical B. Thoracic C. Lumbar D. None of the above

The __________ supplies blood to the face. A. Iliac artery B. Internal carotid artery C. External carotid artery D. Vertebro-basilar artery

The ____________ is responsible for the knocking noise the system makes while the sequence is in progress. A. Patient table moving from one slice location to another B. RF energy being transmitted C. Rapid change/switching of the magnetic field by the gradient coils D. Patient knocking on the bore to get out

The common iliac veins join to form the: A. Abdominal aorta B. Subclavian vein C. Inferior vena cava D. Superior vena cava

The difference in chemical shift is approximately ______ parts-per-million A. 1.5 B. 2.5 C. 3.5 D. 4.5

The duty cycle can be viewed as the: A. MRI technologist job description B. coil acceleration factor C. active gradient time D. measure of flip angle accuracy

The fastest sequence commonly and currently available is: A. Fast spin echo B. Inversion recovery C. Echo planar imaging D. Gradient echo

The final result in a perfusion study is: A. MIPped images of vascular anatomy B. A spectrum of specific detected metabolites C. A set of calculated images which indicate various flow characteristics D. Calculated MPR images of a 3D data set

The final result in a spectroscopy study is: A. MIPped images of vascular anatomy B. Calculated images which indicate various flow characteristics C. A spectrum of specific detected metabolites D. Calculated MPR images of a 3D data set

The gradient that is on during the production of the echo is the: A. Slice select gradient B. Phase encoding gradient C. Frequency encoding gradient D. Inversion recovery gradient

The ideal scan plane in spine imaging for evaluation of the degree of posterior disc herniation as well as intervertebral disc height would be: A. Axial B. Coronal C. Sagittal D. Trans-sphenoidal

The intensity limit for a static magnetic field in clinical use is limited by the Food and Drug Administration (FDA) to _____________? A. 1 Tesla B. 3 Tesla C. 4 Tesla D. 7 Tesla

The ligamentum flavum can be found in which part of the body? A. Abdomen B. Brain C. Spine D. Thorax

The liquid cryogens are cooled in a superconducting magnet at a temperature of _________? A. 1° Celsius B. 1° Fahrenheit C. 4° Kelvin D. 4° Celsius

The local RF coil used to image a human brain is typically located/kept in the __________. A. Equipment room B. Scan control room C. Magnet room D. Patient waiting room

The maximum intensity projection algorithm: A. Separates the k-space phase and frequency modulations into images B. Subtracts a mask from a contrast image, leaving only blood vessels C. Projects the high intensity pixels which represent blood vessels/ducts into one image D. Calculates the frequencies required for 90° and 180° RF pulses

The medial and lateral rectus muscles are located in the: A. Ears B. Gluteus maximus C. Eyes D. Outer neck regions

The most common positive contrast agent used in clinical MR imaging is: A. Barium B. Blueberry juice C. Gadolinium D. Ionic contrast

The optimal imaging plane for visualization of a TFCC( Found in wrist) tear is: A. Axial B. Sagittal C. Coronal D. Perpendicular to glenoid

The orientation of the main magnetic field in a high field, superconducting, short bore magnet is: A. Vertical B. Cylindrical C. Horizontal D. Asymmetrical

The signal produced immediately following an RF pulse is: A. Ham radio signal B. Gradient echo C. FID D. MIP

The timing of the RF pulses in an MRI pulse sequence controls: A. How long the procedure takes B. Pixel size C. Image contrast D. Spatial resolution

The unit of measurement of the magnetic field surrounding the periphery of the MR scanner is expressed as: A. Ohm B. Volts C. Gauss D. Tesla

To accurately depict the VII and VIII cranial nerves, the patient would centered at the level of the: A. Nasion B. Glabella C. External auditory meatus D. Gonion

To obtain a thin slice thickness: A. A shallow gradient is applied with the transmit bandwidth at the Larmor frequency of H B. A shallow gradient is applied with the receiver bandwidth at the Larmor frequency of H C. A steep gradient is applied with the transmit bandwidth at the Larmor frequency of H D. A steep gradient is applied with the receiver bandwidth at the Larmor frequency of H

VoLumen would be selected for which MR procedure? A. MRCP B. MR perfusion C. MR enterography D. MRA abdomen E. MRA intracranial circulation

What are the parameters that make a FLAIR possible? A. Long TR, Short TE, Long TI B. Short TR, Short TE, Short TI C. Long TR, Long TE, Long TI D. Short TR, Long TE, Short TI

What formula is used to calculate the size of the pixel? A. Matrix ÷ FOV B. FOV ÷ slice thickness C. FOV ÷ matrix D. Slice thickness ÷ matrix

What is an inversion recovery? A. 90° RF followed by 180° RF B. 90° RF followed by train of 180° RF pulses C .180° RF followed by 90°RF D. variable° RF followed by gradient to produce echo

What is the TR range for a T2 contrast weighted image ? A 350-700ms B. 1600- 4000ms C. 2000- 6000ms D 80 - 120ms

What specifically is a SPGR sequence spoiling? A. The hippocampus B. Longitudinal magnetization C. Transverse magnetization D. Gradient amplitude

What would the pixel shift be in a sequence acquired at 1.5Tesla (220 Hz) with a 224 matrix and a BW of 26.8 kHz? A. 0.8 B. 1.2 C. 1.8 D. 2.0 E. 2.8

When imaging a geriatric patient, while performing a PCA MRA sequence, what imaging parameter might the operator adjust? A. Slice thickness B. Presaturation band location C. VENC D. Power injector timing

When imaging the extremities, _______________ would be used as a marker to delineate the area of interest for both radiologist and referring physician. A. Duck sauce B. Vitamin B12 tablet C. Vitamin E tablet D. Lead dot marker

When performing MRI to rule out brain tumors, the weighted images acquired to evaluate the extent of lesion involvement, after injection of gadolinium, are: A. Proton density B. Inversion recovery C. T1 D. T2 E. Gradient echo

When positioning a patient for a brain MRI, the centering should be placed at what anatomical landmark? A. External auditory meatus B. Glabella C. Nasion D. Gonion

When would sterile technique be utilized? A. Upon receiving an isolation patient in the MRI suite B. When placing ECG leads on a patient's chest for a cardiac MR C. When performing any procedure that would puncture a patient's skin D. All of the above

Where can avascular necrosis primarily be found? A. Greater trochanter B. Adductor muscle C. Femoral head D. Femoral neck

Which factors affect the flip angle? A. Gradient slew rate and the magnetic field strength B. Duty cycle and RF field C. Strength and duration of the RF field D. Static magnetic field and gradient rise time

Which of the following MR angiography techniques has a scan time short enough to complete an abdominal study in a single breath hold? A. Time of flight B. Phase contrast C. Contrast enhanced D. Spectroscopy

Which of the following combinations of flip angle (FA) and TR would produce a T2 weighted gradient echo? A. 45 TR; 30º flip angle B. 45 TR; 90º flip angle C. 450 TR; 30º flip angle D. 450 TR; 90º flip angle

Which of the following is NOT a metabolite found in a 1H spectrum of normal brain tissue? A. Creatine B. Lactate C. Succinylcholine D. N-acetyl aspartic acid

Which of the following is NOT a result of reducing the FOV? A. Improved spatial resolution B. Decreased signal-to-noise C. Anatomical structures are displayed smaller in the image D. The pixel size becomes smaller

Which of the following situations would NOT violate ARRT ethics? A. Engaging your co-workers opinion regarding proceeding with a procedure in spite of an incorrect order B. Performing the procedure on a patient with an incorrect order C. Reaching out to an ordering MD when an incorrect order has been placed D. Proceeding with a procedure without the request of a physician

Which of the following would NOT compensate for the change in signal-to-noise as a result of decreasing the FOV? A. Reducing the image matrix B. Reducing the number of echo train lengths C. Reducing the number of excitations D. Increasing slice thickness

Which set of scan parameters below would yield the best spatial resolution? A. 270 mm FOV, 192 x 512 matrix, 5mm slice thickness, 8 NEX B. 270 mm FOV, 256 x 512 matrix, 5mm slice thickness, 4 NEX C. 200 mm FOV, 512 x 512 matrix, 3mm slice thickness, 4 NEX D. 200 mm FOV, 512 x 512 matrix, 5mm slice thickness, 4 NEX

Which structure lies adjacent to the head of the caudate nucleus? A. Lentiform B. Medulla oblongota C. Anterior horn of the lateral ventricle D. Posterior horn of the lateral ventricle

With a recFOV that is twice as tall as it is wide, and the phase direction oriented along the smaller "width" dimension of the FOV, which of the following relationships between the frequency and phase steps yields square pixels? A. Frequency steps must be half the phase encoding steps B. Phase steps must equal the number of frequency steps C. Phase steps must be half the number of frequency steps D. The pixels will always be rectangular

With regards to k-space, the data containing signal and contrast information are located along: A. X gradient B. The phase axis C. The central lines D. The outer lines

________ is defined as a patient's permission to a medical or surgical procedure or to participation in a clinical study after being properly advised of the relevant medical facts and the risks involved. A. Res Ipsa Loquitur B. Implied consent C. Informed consent D. Statutory law

_________ magnets can be "shut off" the quickest in case of an emergency. A. Permanent B. Superconducting C. Resistive D. Refrigerator

___________ could be used to line the walls and/or floors of the MR magnet room to reduce the fringe field, and is defined as __________ shielding. A. Copper; active B. Steel; active C. Steel; passive D. Copper; passive E. Lead; passive

___________ is a failure to exercise the care that a reasonably prudent person would exercise in like circumstances. A. Res Ipsa Loquitur B. Respondeat Superior C. Negligence D. Statutory law

____________ and _____________ won the 2003 Nobel Prize in medicine for their work in the 1970's developing MR imaging techniques and capabilities A. Faulkner; Roth B. Faraday; Larmor C. Lauterbur; Mansfield D. Ernst; Damadian

____________ developed the mathematical equation to analyze the heat transfer between solid bodies, later becoming the basis for the rapid processing of phase and frequency signals in MRI. A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. Michael Faraday

____________ is used as an anti-peristalsis agent in MR Enterography procedures. A. Barium B. Gadolinium C. Glucagon D. Paragon

______________ discovered the spin echo phenomenon for nuclear magnetic resonance measurements. A. Sir Joseph Larmor B. Hans Christian Oersted C. Erwin Hahn D. Raymond Damadian E. Michael Faraday

ll of the following EXCEPT ______ are muscles that comprise the rotator cuff. A. Supraspinatus B. Infraspinatus C. Sternoclavicular D. Subscapularis E. Teres minor

Calculate the scan time for a fast spin echo sequence with the following parameters: FOV 20cm, TR 3000, TE 120, 224 x 256 matrix, 3 NEX, 5 mm slice thickness, 12 ETL. A. 2 min 8 sec B. 2 min 34 sec C. 2 min 48 sec D. 2 min 59 sec E. 3 min 4 sec

C ; TR x Phase matrix (smaller #) x NEX / ETL =milliseconds Divide by 1000 to put in seconds

On T1 weighted images of the spine, the CSF (cerebrospinal fluid) appears: A. Isointense to the spinal cord B. Hyperintense to the spinal cord C. Hypointense to the spinal cord D. None of the above

C Hypointense = low signal intensity

Calculate the pixel size for a fast spin echo sequence with the following parameters: FOV 28cm, TR 2000, TE 30, 256 x 320 matrix, 2 NEX, 4 mm slice thickness, 8 ETL. A. 0.089 mm x 0.078 mm B. 1.89 mm x 0.78 mm C. 1.09 mm x 0.88 mm D. 1.78 mm x 0.98 mm

C; FOV/ matrix. Make sure all units are in same measurements. CM vs MM

On a T1 weighted image, edema appears dark because it has a ____________ relaxation time. A. Short T1 B. Short T2 C. Long T1 D. Long T2

C; On a T1 weighted image, edema appears dark because fluid has a long T1 relaxation time.

Calculate the pixel area for a fast spin echo sequence with the following parameters: FOV 28cm, TR 2000, TE 30, 256 x 320 matrix, 2 NEX, 4 mm slice thickness, 8 ETL. A. 0.56 mm2 B. 0.69 mm2 C. 0.96 mm2 D. 1.97 mm2 E. 3.84 mm2

C; Phase x freq ( 28/256) x (28/320) =.0095 cm

Calculate the scan time for a fast spin echo sequence with the following parameters: TR 1800, TE 25, 208 x 224 matrix, 4 NEX, 3 mm slice thickness, 8 ETL. A. 2 min 24 sec B. 2 min 53 sec C. 3 min 7 sec D. 3 min 12 sec E. 3 min 20 sec

C; TR x Phase matrix (smaller #) x NEX / ETL =milliseconds Divide by 1000 to put in seconds

Calculate the scan time for a 3D gradient echo sequence with the following parameters: FOV 16cm, TR 25, TE 12, 208 x 256 matrix, 1 NEX, 4 mm slice thickness, 36 slices. A. 2 min 24 sec B. 2 min 53 sec C. 3 min 7 sec D. 3 min 12 sec E. 4 min 56 sec

C; TR x Phase matrix x NEX x #slices / 1000

______ Discovered that tumors and normal tissue can be distinguished by NMR because their relaxation times.

Damadian

How does a decrease of FOV affect parameters

Decreased SNR and coverage area time is unaffected increased spatial resolution

How does decrease in TR affect parameters ?

Decreased SNR, scan time, # of Slices. Increased T 1 weighting, SAR

How does a decrease of NEX affect parameters

Decreased SNR, scan time, SAR, motion

Which of the following can be considered an advantage of selecting a 3D acquisition as opposed to a 2D acquisition? A. The slices have a greater SNR B. No crosstalk C. Longer repetition times D. All of the above E. A & B only

Which of the following should be educated about static magnetic fields and their effects? A. Anesthesiologists administering conscious sedation B. Nurses accompanying ICU patients C. Respiratory therapists maintaining ventilation D. Housekeeping department that cleans the scan room E. All of the above

________________ developed equations describing how electric and magnetic fields are generated and altered by each other and by charges and currents. A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. James Clerk Maxwell

_________________ discovered that when a magnet was moved inside a coil of copper wire, a tiny electric current flows through the wire. A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. Michael Faraday

Decreasing the receiver bandwidth (utilizing a narrow BW): A. Reduces readout time B. Increases readout time C. Does not affect the readout time D. Increases SNR E. A and D only F. B and D only

In order to produce an echo in a gradient echo pulse sequence, a ___________ is used. A. RF pulse B. Gradient field C. Combination of two RF pulses D. 180° pulse, then 90° pulse E. All of the above F. A & B only

Reducing the TR: A. Increases the SNR of the image B. Decreases the SNR of the image C. Decreases the contrast based on the T2 relaxation time D. Increases saturation effects E. A and D only F. B and D only G. B, C and D only

The following items are typically permitted access to enter a high field MRI system during an MRI guided core biopsy: A. Stainless steel scissors B. Iron-housed spotlight C. Aluminum interventional equipment D. Sterile nonferrous biopsy tray E. None of the above F. C and/or D

Which of the following is exempt from basic MR screening procedures? A. Radiologists B. Patient C. Family member/visitor D. Housekeeping staff E. Nursing staff F. None of the above

The individual nerve roots that leave the lower portion of the spinal cord and progress downward are termed the _____ "horses tail"

Cauda equina

Shim coils

Coils positioned near the main magnetic field that have a small current, and are used to provide localized magnetic fields improving homogeneity

Gradient Coils

Coils used to generate magnetic gradient fields. Gradient coils are operated in pairs in the magnet, at the same current, however, of opposite polarities Gradient Echo - Echo generated by switching a pair of dephasing and rephasing gradients, without the use of a 180° refocusing pulse (seen in spin echo sequences)

A ___________ is an instrument (or document) that allows a patient to appoint an agent to make health care decisions in the event that the primary individual is incapable of executing such decisions. A. Tort doctrine B. Standard of care C. Respondeat superior D. Health care proxy

A disease that is characterized by narrowing of the aorta is called an _____________. A. Aortic stenosis B. Aortic aneurysm C. Aortic dissection D. Aortic coarctation

A patient with a history of _______ should have their GFR checked prior to the administration of IV contrast. A. Kidney disease B. Hypertension C. Diabetes D. All of the above

A system operating at 30,000 Gauss has a field strength of: A. 0.3 Tesla B. 1 Tesla C. 1.5 Tesla D. 3 Tesla

A useful sequence for the evaluation of bone contusions or fractures is: A. T2 weighted images B. FLAIR C. DWI D. STIR

Acquiring a bit more than half the phase k-space samples, then interpolating the data with zeroes for the remaining half is a technique known as: A. Half Fourier B. Zero fill C. Fast spin echo D. A and/or B

All of the following are true regarding RF EXCEPT: A. The RF pulse stimulates the protons into parallel or anti-parallel alignment B. Relaxation begins after the RF is turned off C. RF stimulates the protons to be in phase D. RF converts FID into an echo

An extracranial MRA exam is defined as an MRA of the ____________? A. Circle of willis B. Iliac bifurcation C. Renal arteries D. Carotid arteries

An image acquired in the shoulder parallel to the supraspinatus tendon utilizes the ____ gradient? A. X B. Y C. XZ D. YX

An imaging option used to compensate for CSF flow in the Cervical spine would be: A. Spectral fat suppression B. Anterior saturation band C. Anti aliasing D. Gradient moment nulling

An indication for injecting a patient with Gadolinium contrast for an MRI of the lumbar spine would be: A. Back pain B. Sciatica C. Disc bulge D. Prior surgery E. The imaging center down the street injects for lumbars

As the TE is increased, I. The available number of slices is increased II. The available number of slices is decreased III. SNR increases IV. T1 contrast is maximized A. I and III only B. II and III only C. I only D. II only E. I, II, III and IV

As the flip angle is doubled, the RF absorption increases by a factor of __________. A. 1 B. 2 C. 3 D. 4

Assuming all other parameters are the same, a ___________ ms TR provides the best signal-to-noise ratio. A. 30 B. 200 C. 500 D. 800

At 1 Tesla the frequency difference between that of fat and water is approximately: A. 36 Hz B. 42.57 MHz C. 63.86 MHz D. 147 Hz

Blood flow velocities are greater: A. In a 3D time of flight sequence B. Farther away from the heart C. Along the vessel wall D. At the center of a vessel

Cables from RF coils and gating leads should be: A. Coiled, preferably into a figure "8" B. Nicely formed into loops in the magnet bore C. Resting on the patient's arm or leg to immobilize the cables D. Braided and positioned straight in the bore

Cables from RF coils and gating/trigger leads should be: A. Coiled, preferably into a figure "8" B. Nicely formed into loops in the magnet bore C. Resting on the patient's arm or leg to immobilize the cables D. Braided and positioned straight in the bore

Calculate the Larmor frequency for H at 0.5Tesla. A. 42.57 Mhz B. 63.86 Mhz C. 127 Mhz D. 21.28 Mhz

Calculate the dose of contrast (0.1mmol/kg) that should be administered to a patient weighing 176 lbs with normal kidney function in a routine MR examination. A. 7mL B. 9mL C. 13mL D. 16mL E. 18mL

Common problems in DWI include: A. Bulk patient motion B. Low signal-to-noise ratio C. Sensitivity to magnetic susceptibility when using echo planar readout D. All of the above

Complete saturation is a condition where: A. Spin density effects dominate contrast B. The signal from fluid is inverted from a long TI C. Transverse magnetization is not allowed to recover between excitations D. Longitudinal magnetization is not allowed to recover between excitations

Contrast in Diffusion Weighted Imaging (DWI) depends on: A. The degree to which molecular mobility is impaired (water restriction) B. The sensitivity of the sequence to Brownian motion C. The direction of water diffusion D. All of the above

Conventional spin echo sequences begin with a __________ RF excitation pulse. A. 25° B. 45° C. 180° D. None of the above

Corrective measures in abdominal MR imaging to reduce artifact and improve image quality include: A. Respiratory triggering B. Increase phase matrix C. Parallel imaging to shorten breath holds D. A & C E. None of the above

Current FDA limits on time varying magnetic fields are: A. 23T/sec B. 5G/cm C. 20G/cm D. Once the patient experiences peripheral nerve stimulation

DCE refers to: A. Dual Contrast Examination B. Dynamic Coefficient Exponential C. Double Coupling Examination D. Dynamic Contrast Enhancement

Decreasing rBW (receiver bandwidth)by a factor of two: A. Decreases SNR by 2 B. Increases SNR by 2 C. Decreases SNR by √2 D. Increases SNR by √2 E. Increases SNR by 4 F. Decreases SNR by 4

Decreasing the TR will: A. Lower SNR B. Reduce scan time C. Increase SNR D. Both A and B

Doubling field strength will result in what impact on SAR potential, if any? A. Half-SAR B. No change C. Double SAR D. Quadruple SAR

During a quench of the MR system, patients and employees should be evacuated from the scan room to avoid ______________. A. Damage to tympanic membranes B. Frostbite C. Asphyxiation D. All of the above

Each train of echoes has what effect on the pulse sequence in a fast spin echo? A. Increases SAR absorption B. Reduces scan time C. Lowers SNR D. All of the above

Field strength at magnet isocenter is measured in units of: A. Ohm B. Volts C. Gauss D. Tesla

Flow before an area of stenosis is defined as: A. Spiral flow B. Turbulent flow C. Vortex flow D. Laminar flow

Following the injection of contrast, which of the following patients are most likely to have a potentially serious reaction? A. Anemic patients B. Those with a high BUN C. Hypertensive patients D. Those with asthma or allergic respiratory disorders E. Claustrophobic patients

Force on an object in an magnetic environment depends on: I. Mass of the object II. Strength of the magnetic field III. Strength of the RF field IV. Ferromagnetic properties of the object A. I only B. I and II C. I, II, and III D. I, II, and IV E. I, II, III and IV

Functional MRI (fMRI) was developed in: A. 1946 B. 1954 C. 1977 D. 1991

Hemosiderin is defined as the abnormal accumulation of: A. Fluid on the brain B. Infection in the thecal sac C. Stenosis in the carotid artery D. Iron in blood cells

In a gradient echo sequence, reducing the flip angle while maintaining the TR reduces: A. Scan time B. T2* contrast C. Inversion delay D. Saturation

In one T1 relaxation time: A. 67% of the longitudinal magnetization has decayed B. 67% of the transverse magnetization has decayed C. 63% of the transverse magnetization has recovered D. 63% of the longitudinal magnetization has recovered

In order to generate an MR image, the slice select gradient must be turned on during: A. T1 relaxation B. Collection of the echo C. Patient positioning D. RF energy application

It is ___________ that every patient having an MRI be provided auditory protection in the form ______________. A. Mandatory; lead shield B. Recommended; cotton balls C. Mandatory; earplugs and/or headphones D. Recommended; earplugs and/or headphones

LPM stands for: A. Lateral precessional magnitude B. Larmor physicist of magnetics C. Licensed physical medicinist D. Liters per minute

Magnetic field inhomogeneity is expressed in: A. Watts per kilogram B. Gauss per centimeter C. Tesla per meter D. Parts per million

Multiplanar reconstructions are typically utilized in 3D pulse sequences because: A. 2D slices are too thick to reformat B. 2D slice groups are too long C. There are gaps between 2D slices D. A & C only E. B & C only

Multiple coil elements combined with multiple receiver channels make a: A. Surface coil B. Circularly polarized coil C. Quadrature coil D. Phased array coil

NEX is short for: A. Number of excellent technologists B. Nulling excitement C. Net excitation factor D. Number of excitations

NMV is short for: A. Net magnitude vortex B. Nuclear magnetic voxel C. Nuclear mottled vertical D. Net magnetization vector

Patients in need of MRI IV gadolinium contrast should first have their glomerular filtration rate (GFR) checked if they: A. Have a history of renal disease B. Have a history of diabetes C. Are over the age of 60 D. All of the above

Presaturation pulses are often used to: A. Improve spatial resolution B. Improve temporal resolution C. Reduce scan time D. Reduce flow artifacts E. Enable bright signal from flowing blood

Prior to entering the MRI scan room, a patient should be screened for: A. Surgical history/implants B. Pregnancy C. Prior trauma or injury D. All of the above

RF heating is more of a concern in ________ sequences. A. Gradient echo B. Inversion recovery C. Perfusion D. Fast spin echo

Radiofrequency (RF) shielding can be achieved by lining the scanner room walls with: A. Lead B. Aluminum C. Steel plates D. Copper

Reducing the phase matrix from 256 to 192 will: A. Increase the signal-to-noise ratio B. Decrease imaging time C. Decrease spatial resolution D. All of the above

Slice ___________ is determined by the slice selection process. A. Position B. Orientation C. Thickness D. All of the above

TI is short for: A. A rapper B. Time to Invent C. Internal echo Time D. Inversion Time

The Ernst angle can be defined as the optimal ___________ that yields the ____________ signal for a particular spin in the least amount of time. A. NSA; minimum B. TR; maximum C. Flip angle; minimum D. Flip angle; maximum

The FDA limit on time varying magnetic fields is __________. A. 5T/sec B. 12G/cm C. 20T/sec D. Once the patient experiences peripheral nerve stimulation

The HEIGHT of a peak on an MR spectrum correlates to the _________ of a substance that was detected. A. Frequency B. T2 weighting C. Malignancy D. Amount

The SI unit of magnetic field strength is named after: A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. Michael Faraday

The effects of time varying magnetic fields can include all of the following EXCEPT: A. Peripheral nerve stimulation B. Magnetophosphenes C. Acoustic damage and/or hearing loss D. Warmth and/or increase in body temperature

The extent to which a material or tissue becomes magnetized in an external magnetic field is called: A. Magnetic inversion B. Contrast to noise ratio C. Tau time D. Magnetic susceptibility

The force that an object can be attracted to the magnetic field is reliant upon: A. The field strength (Tesla) of the MR system B. The mass of the projectile C. The specific ferromagnetic nature/properties of the material D. All of the above

The gradient slew rate is the: A. Time it takes for the gradient to reach its full amplitude B. Time it takes longitudinal magnetization to regrow C. Time between TI and initial RF pulse D. Rate of speed of ascent or descent of a gradient from zero to its maximum amplitude

The imaging technique that employs a very rapid pulse sequence while the patient is at rest or performing a task is: A. Perfusion B. Diffusion tensor imaging C. Spectroscopy D. Functional MRI

The location of the coils installed in the MRI scanner, from the inner point closest to the patient to the outer most edge, are: A. Main magnet, gradient coils, shim coils, RF coils B. Gradient coils, RF coils, shim coils, main magnet C. Radiofrequency coils, shim coils, gradient coils, main magnet D. Radiofrequency coils, gradient coils, shim coils, main magnet

The major bifurcation of the abdominal aorta is the: A. Carotid arteries B. Right and left femoral arteries C. Right and left hepatic arteries D. Right and left iliac arteries

The measurement of radiofrequency absorption is delineated as: A. Watts per pound B. dB/dT C. Volts per kilogram D. Watts per kilogram

The minimum acceptable method for detection of intra-ocular ferrous foreign bodies is: A. Ferromagnetic Detection systems B. Cat Scan C. Finger sweep D. X-ray

The primary biological effect of radiofrequency fields is ____________. A. Magnetophosphenes B. Hypertension C. Claustrophobia D. Tissue heating

The process that digitizes the MR signals is known as: A. Hahn echos B. Faraday's law C. Gyromagnetic reconstruction D. Fourier transform

The prostate gland is located __________ and __________ to the bladder. A. Anterior; superior B. Posterior; superior C. Anterior; inferior D. Posterior; inferior

The repetition time is the: A. Time between the 180º inverting pulse and the 90º RF excitation pulse B. Time between the 90º RF pulse and the peak of the signal in the receiver coil C. Time it takes for the flip angle to reach the Ernst angle of peak signal D. Time between two 90º RF pulses

The timing of RF pulses in an MRI pulse sequence controls: A. Resolution capabilities B. Amount of signal in the image C. The time the coil receives the echo D. Image contrast

The vertebral arteries originate from the ____________. A. Aortic arch B. Abdominal aorta C. Basilar artery D. Right and left subclavian arteries

To increase the voxel volume, which parameters would be adjusted? A. Slice thickness and interslice gap B. Matrix, slice thickness and slice gap C. FOV, slice gap and matrix D. FOV, slice thickness and matrix

Visitors and site employees entering the MR scan room with the patient ____________. A. MUST be shielded with lead aprons while the magnet is scanning B. do not have to be screened for metal as they are not being scanned C. can bring cellular and portable listening devices in the room D. should be carefully screened for metal in the same manner as the patient

VoLumen is a contrast agent used for: A. Vessel lumen relaxivity B. Volume rendering MRCP C. Blood brain barrier D. Bowel enhancement

Water has a __________ T1 relaxation time and a ________ T2 relaxation time. A. short; short B. short; long C. long; short D. long; long

What element in the body is the principal nucleus utilized in clinical MR imaging? A. Calcium B. Oxygen C. Helium D. Hydrogen

What has a higher precessional frequency? A. Grey matter B. Bone C. Fat D. Water

What is a gradient echo? A. 90° RF followed by 180° RF B. 90° RF followed by train of 180° RF pulses C. 180° RF followed by 90°RF D. variable° RF followed by gradient to produce echo

What is defined as the excess number of hydrogen protons aligned with the static magnetic field direction (B0)? A. Transverse magnetization B. TE C. Gyromagnetic ratio D. Longitudinal magnetization

What protocol would be selected to rule out islet cell tumor? A. Liver with volumes B. Pelvic floor laxity C. Adrenal glands wtih in/out of phase D. Pancreas

Which of the following is short for 2 times/daily? A. PO B. Tid C. Qid D. Bid

Which of the following is the thickest and strongest tendon in the body? A. Supraspinatus B. Patella C. Flexor D. Achilles E. Quadriceps

Which of the following pulse sequence parameter combinations would yield an image with the most blurring? A. 400TR, 25TE, 256 x 256, 5mm slice thickness, 1NSA B. 2000TR, 30TE, 256 x 256, 5mm slice thickness, 6 ETL, 2NSA C. 4000TR, 60TE, 256 x 256, 5mm slice thickness, 12 ETL, 4NSA D. 6000TR, 80TE, 256 x 256, 5mm slice thickness, 16 ETL, 4NSA

Which of the following sequences is the most insensitive to magnetic field inhomogeneity? A. RF spoiled gradient echo B. Steady state rephased gradient echo C. Echo planar D. Spin echo

Which of the following sequences would be more at risk for the effects that time varying magnetic fields can cause? A. SE B. FSE C. GE D. EPI

Which of the following statements is FALSE regarding the use of a narrow receiver bandwidth? A. It generates lower signal-to-noise ratio images B. It should be applied in anatomical regions that contain high fat and water interfaces C. It is utilized with a high readout gradient amplitude D. All of the above

Which of the following's primary biological effect is tissue heating/deposition? A. Static magnetic fields B. Gravitational earth magnetic fields C. Time varying magnetic fields (gradient) D. Oscillating magnetic fields (radiofrequency)

Which protocol would be selected for an exam requiring attention to the parotid gland? A. MRA neck B. Male pelvis C. Mediastinum D. Soft tissue neck

With regards to k-space, the data containing high resolution are located along: A. The Z gradient B. The phase axis C. The central lines D. The outer lines

______ is when only half the views of k-space are filled in the frequency axis. A. Diffusion tensor B. Anti aliasing C. Half Fourier D. Partial or fractional echo

_______ sequences are performed to suppress CSF (cerebro-spinal fluid)and aid in the detection of demyelination. A. T1 weighted B. STIR C. T2 weighted D. FLAIR

____________ discovered and developed the first rotating magnetic field. A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. Michael Faraday

____________ is a condition in which part of the cerebellar tonsil is displaced through the foramen magnum. A. Hydrocephalus B. PRES C. Cavernous Angioma D. Chiari Malformation

____________ states that a changing magnetic field will induce a voltage. A. Maxwell's equations B. Bloch equations C. Gilbert's law of relativity D. Faraday's law of induction

_____________ occurs after initial RF application, causing phase differences to appear between precessing spins, resulting in decay of transverse magnetization. A. Weighting B. Precession C. Recovery D. Dephasing

_____________ requires that a patient's information be kept confidential and not shared or released unless required by law. A. Res Ipsa Loquitur B. Respondeat Superior C. Tort D. HIPAA

_____________developed equation showing precession of nuclear spins being proportional to magnetic field strength A. Raymond Damadian B. Felix Bloch C. Richard Ernst D. Sir Joseph Larmor

mL is an abbreviation for: A. MilliLarmor B. MegaLiters C. MagnaLaude D. MilliLiter

What would the scan time be in a 3D volume acquisition as follows: TR 32 ms, TE 4 ms, Flip Angle 15°, FOV 18cm, 2mm slice thickness, 96 slices, 192 x 256 matrix, 1 NEX? A. 4 min 28 sec B. 5 min 12 sec C. 8 min 42 sec D. 9 min 50 sec

D. TR x phase matrix x NEX x slices / 1000 32ms x 192 x 1 x 96= 589,824Ms/ 1000= 589.8 sec/ 60= 9.8min

The vertebral body will display a ____ signal intensity on T1 weighted images in the pretense of fracture, infection or neoplasm?

Hypointense. These factors cause a reduction of signal in T1 weighted due to reduction or replacement of bone marrow.

T1 Weighting

Image contrast created with short TR's and short TE's whose contrast is determined by the T1 times of tissues

Effective TE

In a pulse sequence, the contrast and overall SNR of an image is determined by the position of the echo when the phase encoding gradient has the smallest amplitude. At this time, the echo signal has the strongest signal and undergoes minimal dephasing. The time between the initial RF excitation pulse and this time is the effective echo time (TEeff)

dB/dt

Formula for the temporal change of the magnetic field, especially important with regards to patient safety in relation to gradients. This is due to the electrical field generated in conductive materials, as in human tissue

Half

Fourier - Due to the symmetry of the matrix to be sampled, a little more than half of the raw data is necessary to be acquired, reconstructing the remaining data to complete the image, greatly reducing scan time

Increasing the TE: A. Increases the contrast based on T1 tissue relaxation times B. Decreases the SNR of the image C. Decreases the contrast based on T2 tissue relaxation times D. Increases the contrast based on T2 relaxation times E. A and B only F. B and C only G. B and D only

What factors decrease scan time?

Increased ETL, rBW,

How does a decrease in ETL affect parameters ?

Increased SNR, scan time Decreased SAR and blurring

Which factors will give you decreased SNR?

Increased TE, ETL, TI, phase matrix, rBW

Which factors will give you increased SNR?

Increased TR, FOV, NEX, Flip angle , slice thickness

What factors increase scan time

Increased TR, TE, NEX, TI, Phase matrix, # of slices

Calculate the voxel volume for a fast spin echo sequence with the following parameters: FOV 20cm, TR 3000, TE 120, 224 x 256 matrix, 3 NEX, 5 mm slice thickness, 12 ETL. A. 0.56 mm3 B. 0.69 mm2 C. 1.88 mm2 D. 3.45 mm3 E. 5.69 mm3

Pixel area x slice thickness; pixel area= phase pixel size x freq pixel size; FOVcm x 10 to make mm 200 fov 200/ 224 x 200/256 = 0.697 ( pixel area) 0.697 x 5 = 3.48

The location of the coils installed in the MRI scanner, from the inner point closest to the patient to the outer most edge, are

RF radiofrequency coils, gradient coils, shim coils, main magnet

Signal to Noise Ratio (SNR)

Ratio between the amplitude of the received signal and background noise

Longitudinal relaxation

Return of longitudinal magnetization to its equilibrium value after RF excitation due to the exchange of energy between the nuclear spins and the lattice

Inhomogeneity

Lack of homogeneity or uniformity in the main magnetic field

In 1975, _____ introduced 2D NMR using phase and frequency encoding, and the Fourier transform

Richard Ernst

Passive shielding

Lining the MR room with steel or other ferromagnetic plating, thus reducing the scope and distance of the fringe field

Radiofrequency is low or High energy and ionizing or non ionizing?

Low/ non ionizing

Tesla

SI unit of magnetic field strength

A useful sequence for the evaluation of bone contusions or fractures is

STIR (Short T1 inversion recovery) used to null signal from fat. (Increased T1 reduces signal while increased T2 increases signal. STIR imaging increased T1 & T2 are additive. Allows for longitudinal magnetization for long T1 lesions and remain inverted to produce high signal.

The _______ is the spinal region that is least affected by CSF pulsation

Lumbar

Magnetic resonance spectroscopy (MRS)

MR technique generating a spectrum of metabolites in a specific volume of interest

Magnetic resonance angiography (MRA)

MR technique utilized to image flowing blood and specific vasculature structures

Magnetic resonance elastography (MRE)

MR technique which waves quantitatively assesses the mechanical properties of tissues, based on the propagation of shear

Time of Flight (TOF)

MRA technique relying on flow related enhancement to distinguish between stationary spins and flowing spins

Velocity Encoding (VENC)

MRA technique used for encoding flow velocities

Receiver

MRI equipment device that detects and amplifies the RF signals picked up by the receiver coil

Magnetic field

Magnetic lines of force which extend from a north and south pole to form a closed loop around the outside of a magnetic material. A magnetic field has properties of both magnitude (strength) and direction

The _________ is the soft, jelly-like, inner portion of the intervertebral disc

Nucleus pulposus

NEX

Number of Excitations: how many times each line of k-space data is acquired during the scan, or how many times each slice is repeated to gain signal and reduce noise, improving SNR

NSA

Number of Signals Averaged: see NEX

EPI factor

Number of gradient echoes in an Echo Planar sequence acquired after the initial excitation pulse; equating to the scan time acceleration factor (an EPI factor of 64 is 64 times faster than a routine gradient echo sequence)

When performing lumbar spine images through the intervertebral disc spaces, slices, oriented in the ____ plane would be selected

Oblique transverse plane

Homogeneity

Uniformity of the main magnetic field; a magnetic field is considered homogenous when it has the same field strength across the entire field

On an image of the thoracic spine in the sagittal plane, utilizing a 28cm FOV, the vertebral disc levels can be determined by

Using a large FOV localizer and optional vit E markers to count down from C2

K space

data acquisition matrix containing raw image data prior to image processing. The Fourier transform of k-space is the magnetic resonance image

An image acquired in the shoulder parallel to the supraspinatus tendon utilizes the ______ gradient ?

YX; yields a coronal oblique plane

Diffusion tensor

displays the mobility of water molecules in all three coordinates

Partial volume averaging

a loss of resolution due to excessively large voxels, typically caused by slices that are too thick

Resistive magnet

a magnet that can be turned on and off, and uses the principles of electromagnetism to generate a magnetic field

Orthogonal

a plane or section that is perpendicular to the X,Y, or Z axes

Proton

a positively charged particle located in the nucleus of an atom. The # of protons in the nucleus controls the chemical properties of that element

Precess

a rotational motion about an axis of a vector whose origin is fixed at the origin of the coordinate system

Presaturation

a technique employing repeated RF excitation of tissues outside the ROI for the purpose of reducing or eliminating their phase effect artifacts

Phase coherence

a term describing the degree to which precessing nuclear spins are synchronous

Free Induction Decay

a time based electrical signal that is detected in a nuclear magnetic resonance spectrometer, that is produced by induction from the motion of the magnetic moments of nuclei, that decays with time (T2), that can be converted to a more conventional frequency based signal using analysis by Fourier transforms; abbreviated FID

Net magnetization vector (NMV)

a vector which represents the sum of the magnetization from a spin system; the magnitude and direction of the magnetization resulting from the collection of atomic nuclei

Analog

being continuous, or having a continuous range of values

Flow Compensation

an MR technique used to reduce artifacts from spin phase effects through the use of additional gradient pulses. Also known as Gradient Moment Nulling

Multi echo imaging

an MR technique using a series of echoes following a single excitation pulse, usually in the form of 180o RF pulses that generate images

Phase contrast

an MRA technique based on the speed of the vessels of interest, utilizing velocity encoding (VENC)

Transceiver coil

an MRI surface coil that functions as both a transmitter and a receiver

Larmor equation

an equation stating that the frequency of precession of nuclear magnetic moment is directly proportional to the product of the magnetic field strength(B0) and the gyromagnetic ratio

Quench

an event in a superconducting MR system causing a loss of superconductivity, a rapid loss of the magnet cryogens, potentially creating a hazard for patients / operators in the magnet room

Proton Density weighting

an image minimizing T1 and T2 effects, with contrast primarily dependent upon the density of protons in the imaging volume

Neutron

an uncharged neutral particle located in the nucleus of most atoms which serves as a stabilizer

Pathogen

any disease producing agent, especially a virus, bacterium or other microorganism

ADC images

are reconstructed from diffusion weighted images with multiple b- values, and correspond to the spatially distributed diffusion coefficients of the target tissues

Artifacts

are signal misrepresentations that do not correspond to the spatial location of the specific tissue imaged

Cryogens

are the liquids that are supercooled (4° Kelvin) in order to maintain the superconductivity of the magnet coils

Chemical shift

artifact is due to the difference in resonant frequencies between fat and water, causing a phase shift in voxels containing fat and water. Describing image display, the Cine function scrolls through the entire sequence's images, giving the appearance of CSF flowing or cardiac movement, from the cycling of the images acquired; a "movie" function of scrolling images

Crosstalk

artifact occurs when slices are positioned too close together, causing signals from adjacent slices to affect one another. This affects T1 contrast, and is remedied by utilizing an interleaved slice profile or by increasing slice gap

Contrast

can be defined as the signal strength differences between two adjacent tissue types

Passive shimming

Shimming the magnetic field with metal pieces either within or on the outer surface of the magnet bore, for the purpose of a more homogenous magnetic field

STIR

Short TI Inversion Recovery: a version of the Inversion Recovery pulse sequence where the inversion time (TI) is set to 0.69 times the T1 of fat, nulling the signal from fat at the specific field strength in which it's being acquired

For optimal cervical spine patient positioning, optimal patient orientation should be ____ and the coil should be positioned ____ between the levels C1-C7

Supine; posterior to patient

Echo

The MR signal generated by an RF or a gradient pulse

Transverse magnetization

The XY component of the net magnetization, at right angles to the main magnetic field

Longitudinal magnetization

The Z component of the net magnetization vector in the direction of the static magnetic field. Following RF excitation, this vector returns to its equilibrium value at a rate characterized by the time constant T1

Image Resolution

The ability to differentiate adjacent tissue structures. Higher image resolution increases detection of smaller pathologies. Resolution increases with a smaller FOV, higher matrix, and thinner slices

Raw data

The components of the magnetization in the imaging object after excitation, sampled from the receiver coil signal and stored as a function of time during the data acquisition of an MR imaging sequence

Nucleus

The core or center part of an atom, which contains protons having a positive charge and neutrons having no electrical charge, except in hydrogen where the nucleus is a single proton

Gradient Slew rate is defined as

The speed of ascent or decent of the gradient to reach its max or 0. Defined as a positive or negative number. Calculated by amplitude/ rise time OR Strength of gradient over a specific distance

An array processor

comprises a multiprocessor that is switched in sequence and in parallel while simultaneously performing a computing task

Inversion time (TI)

The time between the initial 180o RF and the 90o RF excitation pulse in an Inversion Recovery sequence

Tau

The time between the pulses (btwn 90oRF to 180oRF and 180oRF echo) in spin echo (also known as 1/2 TE)

The primary biological effect of radiofrequency fields is

Tissue heating

RF heating is more of a concern in fast spin echo sequences due to the multiple echo train lengths, leading to potential increases in tissue heating. True or False And why?

True bc the 180 degree RF pulse is 4x the power of the initial 90 degree RF pulse.

Velocity

speed in a particular direction

spin spin or transverse relaxation time

spin-lattice or longitudinal relaxation time

Readout gradient

magnetic field gradient applied during the moment when the echo is formed, and is responsible for frequency encoding in the image

Dephasing

occurs after initial RF application, causing phase differences to appear between precessing spins, resulting in decay of transverse magnetization

Aliasing artifact

occurs when tissue outside the Field of View is undersampled, causing a misregistration of anatomical location, in the phase direction, but on the opposite side of the anatomical location, also known as wrap-around artifact

Spatial resolution

the ability to define adjacent points in an image (detail)

Flip Angle

the angle to which the longitudinal magnetization is tipped into the transverse plane, following the initial RF excitation pulse

Field of View

the base size of the slice to be acquired, measured in dimensions of phase (short axis of anatomy) and frequency (long axis); FOV in short

Sampling

the conversion of analog signals to digital values through a specific measurement process

Resonance

the exchange of energy between two systems at a specific frequency

Flux

the invisible lines of force that extend around a magnetic field, with the greatest strength/force being at the two poles/ends of the magnet

Gradients

the linear increased or decreased change in the magnetic field of a certain orientation. A gradient defines the strength and orientation of change of a magnitude in space

Lattice

the magnetic and thermal environment through which nuclei exchange energy in longitudinal (T1) relaxation

Fourier Transform

the mathematical process of converting raw data into an image suitable for display

Diffusion

the movement of atoms or molecules from an area of higher concentration to an area of lower concentration. (Brownian motion)

Frequency

the number of times that a periodic function or vibration repeats itself in a specified time. It is usually measured in hertz (Hz), where 1 Hz = 1 cycle per second

Phase encoding

the process of locating an MR signal along the phase axis, directly correlating spatial resolution and scan time with the number of phase encodings in an MR image

Frequency Encoding

the process of locating an MR signal in one dimension by applying a magnetic field gradient along that dimension during the period when the signal is being received, utilizing differences in frequencies along the same row in order to spatially differentiate one location from another

Rephasing

the process of returning out of phase magnetic moments to phase coherence, instigated by applying a 180o RF pulse (spin echo) or reversing a magnetic gradient (gradient echo)

Fat Suppression

the process of utilizing specific sequence parameters to null signal from fat in the MR sequence, as in STIR, for example

Ferromagnetism

the property of being strongly attracted to either pole of a magnet. Ferromagnetic materials, such as iron, contain unpaired electrons, each with a small magnetic field of its own, that align readily with each other in response to an external magnetic field

Gyromagnetic Ratio

the ratio of the magnetic moment (field strength) of a rotating charged particle, such as an electron, to its angular momentum (frequency). The value of the gyromagnetic ratio of hydrogen is 42.57 MHz/Tesla

Larmor frequency

the specific frequency at which magnetic resonance in a nucleus can be excited and detected, and varies directly with magnetic field strength

Cardiac triggering

prevents or reduces motion artifacts in the MR image caused by the heartbeat or pulsating blood flow and enables the images to be acquired synchronized to cardiac movement

Paramagnetic

property of magnetism signifying weak magnetic properties due to its unpaired electrons. IV Gadolinium contrast is an example of a paramagnetic substance

Vector

quantity that has both magnitude and direction

see Repetition Time

Gauss

unit of magnetic induction in the centimeter-gram-second system of physical units. Old unit for magnetic field strength. Today, the unit Tesla (T) is used (1 Tesla = 10000 Gauss). The 5 Gauss line is currently used as a safety standard for the exclusion of implanted metallic devices

CE MRA (Contrast enhanced MR angiography

utilizes the reduced T1 relaxation time of blood through the use of an intravenously injected Gadolinium contrast agent

Voxel

volume element with 3 Dimensional characteristics T2 Weighting - Image contrast created with long TR's and long TE's whose contrast is determined by the T2 times of tissues

An intracranial MRA is defined as an MRA of the _______________? A. Circle of willis B. Iliac bifurcation C. Renal arteries D. Carotid arteries

As the TR is increased, I. SNR is increased II. Available number of slices is increased III. T2 information is maximized A. I and II B. I, II and III C. I and III D. None of the above

As the TR is increased, I. SNR is increased II. Available number of slices is increased III. T2 information is maximized A. I and II only B. I and III only C. I only D. II only E. I, II and III

Assuming all other parameters are the same, an echo time of ___________ ms provides the best Signal-to-Noise Ratio. A. 15 B. 30 C. 80 D. 110

CSF suppression is performed with which type of technique? A. FLAIR B. STIR C. FISP D. SPGR

Decreasing the receiver bandwidth (utilizing a narrow BW): A. Increases susceptibility artifact B. Decreases susceptibility artifact C. Does not affect susceptibility artifact D. Decreases SNR E. A and D only F. B and D only

Each line of k-space is defined by the: A. Phase encoding gradient B. Frequency encoding gradient C. Slice select gradient D. Dictionary

Fat has a _______ T1 relaxation time and a ________ T2 relaxation time. A. short; short B. short; long C. long; short D. long; long

Gadolinium chelates used in MR imaging are: A. Paramagnetic B. Diamagnetic C. Ferromagnetic D. Quasimagnetic

Gadolinium is an example of a ___________ contrast agent. A. Paramagnetic B. Diamagnetic C. Super Paramagnetic Iron Oxide D. Ferromagnetic

Gradient echo sequences use flip angles: A. To control saturation effects B. After the 180º pulse C. Between the 90º and the 180º pulses D. To control SAR in bariatric patients

In time-of-flight (TOF) imaging, areas of signal void can be seen on the image due to:I. Turbulent flowII. Vortex flowIII. Laminar flow A. I and II only B. II and III only C. I only D. II only E. I, II and III

Increasing NSA will: A. Improve SNR B. Degrade SNR C. Shorten scan time D. Have no effect on SNR

Law that pertains to crimes and their punishment is defined as: A. Criminal law B. Civil law C. Tort D. Respondeat superior

Metastatic lesions enhance after injecting a gadolinium chelate because of: A. The breakdown in the blood brain barrier B. T2 shortening C. The tangling of arteries and veins in metastatic disease D. None of the above

Reducing the number of lines filled in k-space will produce an image: A. With a decrease in spatial resolution B. With an increase in spatial resolution C. With an decrease in overall SNR D. A and C

What is the optimal slice orientation to view the median nerve? A. Axial B. Sagittal C. Coronal D. None of the above

What is the percentage of patients reported to have allergic reactions to gadolinium contrast agents? A. Less than 1% B. 10% C. 25% D. 50%

What is the second branch of the abdominal aorta? A. Superior mesenteric artery B. Inferior mesenteric artery C. Celiac artery D. Renal artery

When imaging an MRI of the wrist, to achieve high spatial resolution would require the use of: A. Small FOV B. Large FOV C. Thick slice thickness D. Small matrix size

Radiofrequency

A frequency band in the electromagnetic spectrum with frequencies in the millions of cycles per second

Spin

A fundamental property of matter in MR imaging

Double Echo

A spin echo sequence with two echoes, two generated images per slice location

FLAIR (Attenuated Inversion Recovery)

A technique used to suppress fluids, utilizing a long echo time (TE) coupled with a long Inversion Time (TI)

Risk factors of MR exposure with regards to SAR absorption include all of the following EXCEPT: A. Cardiovascular disease B. Hypotension C. Obesity D. Geriatric patients

B Hypertension not Hypo

All of the following comprise the biliary tree EXCEPT: A. Common bile duct B. Hepatic duct C. Mesenteric duct D. Pancreatic duct

All of the following would aid in reducing scan time EXCEPT: A. Utilizing the coarsest matrix possible B. Reducing NEX C. Reducing TE D. Increasing parallel imaging factor E. Setting TR to shortest

An isotropic voxel refers to a __________ shaped voxel. A. Circular B. Rectangular C. Cubic D. Oval

DSC refers to: A. Dual Spin Conversion B. Dynamic Spin Contrast C. Dynamic Susceptibility Contrast D. Digitizer Signals Converted

High field scanners typically have field strengths greater than or equal to: A. 0.3 Tesla B. 0.7 Tesla C. 1.5 Tesla D. 5 Gauss

In order to obtain a time of flight MRA of the IVC a presaturation band would be placed: A. Anterior B. Posterior C. Superior D. Inferior

MR findings of a low volume corpus callosum and increased white matter lesions can be indicative of a diagnosis of: A. Brain tumor B. CVA/Stroke C. Multiple Sclerosis D. Chiari Malformation

NSA is an abbreviation for: A. National society of abbreviators B. Navicular scaphoid angulation C. Number of signals averaged D. Nuclear sequence anonymization E. Neuroradiological sequence adaptability

ROI is short for: A. Return of information B. Relaxation of inversion C. Region of interest D. Relativity of isotrophy

Reducing the FOV (field of view) only will result in: A. Decreased spatial resolution B. Increased signal-to-noise C. Decreased signal-to-noise D. Increased T2 weighting

The first major branch of the abdominal aorta is the _______. A. Superior mesenteric artery B. Inferior mesenteric artery C. Celiac artery D. Renal artery

The precessional frequency of hydrogen, according to the Larmor equation, at 3Tesla is: A. 42.57 MHz B. 63.86 MHz C. 127.71 MHz D. 220 MHz

The readout gradient is usually turned on during the sampling or readout of the peak echo and also during which other process? A. Slice selection B. Phase encoding C. Frequency encoding D. None of the above

________ is defined as an abnormal connection between arteries and veins, usually congenital. A. An aneurysm B. A blood clot C. An AVM D. A dissection

mmol is short for: A. milliliters B. milligram C. millimol D. multimillion

o evaluate for a tear of the anterior cruciate ligament (ACL), positioning the knee would require ___________. A. Flexion of the knee B. Extension of the knee C. 15° external rotation D. 15° internal rotation

At 1.5 Tesla, the chemical shift between fat and water is: A. 63.86 Hz B. 100 Hz C. 220 Hz D. 440 Hz

C; 63.86 x 3.5 (chemical shift) = 220

What is the correct scan time for a spin echo sequence with the following parameters: TR 500 ms, TE 30 ms, matrix 208 x 208, 2 NEX, FOV 200mm? A. 2 minutes, 8 seconds B. 3 minutes 46 seconds C. 3 minutes 28 seconds D. 5 minutes 14 seconds

C; TR x Phase matrix x NEX / 1000

Ways to reduce RF heating effects include

Consistent room temp 65-75, humidity 50-70, sufficient air flow, and appropriate amount of blankets on bariatric patients.

How does Cord & CSF appear in T2 imaging of spine

Cord = Dark (Hypointense) CSF= bright (Hyperintense)

How does cord and CSF appear in T1 imaging of spine

Cord= bright (hyperintense) CSF= dark (hypointense)

Fat only Image

An image yielding only the signals from fat protons in an image and suppressing the signal from water; usually a "phase" of the Dixon technique

Increasing the receiver bandwidth (rBW): A. Increases chemical shift artifacts B. Decreases chemical shift artifacts C. Decreases slice thickness D. Increases slice thickness

Referring to SAR impact on the patient, all of the following parameter changes negatively impact pulse duty cycle EXCEPT: A. Presaturation slab employment B. Reduction in # slices C. Decreased TR D. Fat suppression selection E. Increased ETL

SAR stands for: A. Standard absorption ratio B. Specific absorption rate C. Standard acquisition rate D. Spectral attenuation relaxation

SNR increases with all the following adjustments, EXCEPT: A. Increasing FOV B. Decreasing pixel size C. Increasing NEX/NSA D. Decreasing phase matrix

The CPU used to plot and adjust slices in an MR sequence is located: A. Equipment room B. Scan control room C. Magnet room D. Patient waiting room

The FDA approved oral contrast agent for MRI makes bowel appear: A. T1 & T2 hyperintense B. T1 & T2 hypointense C. T1 hyperintense/ T2 hypointense D. T1 hypointense/ T2 hyperintense

The _____ is located within an equipment room. A. Magnetic shielding B. RF power amplifier C. Gradient coils D. RF coils

The ______ scan plane best demonstrates the degree of spinal stenosis. A. Axial B. Sagittal C. Coronal D. Supraspinatous oblique

The standard dose for the adminstration of IV gadolinium chelates is: A. 1 mmol/kg B. 0.1 mmol/kg C. 0.2 mmol/kg D. 0.1 mmol/lb

Which would be the optimal slice orientation to view the Achilles tendon? A. Axial B. Sagittal C. Coronal D. None of the above

_______________ discovered that a charged particle, such as a proton, spinning around its own axis, has a magnetic field, known as magnetic momentum. A. Paul Lauterbur B. Felix Bloch C. Raymond Damadian D. Michael Faraday

_______________ discovered that a current flowing through a wire could produce a magnetic field. A. Sir Joseph Larmor B. Hans Christian Oersted C. Joseph Fourier D. Nikola Tesla E. Michael Faraday

The smallest object that can be resolved in an image acquired with a 20cm FOV and a 224 x 224 matrix is _________ mm. A. 0.54 B. 0.89 C. 1.12 D. 1.89

B 20 x 10= 200 /224= .89

In a fast spin echo sequence with a 28 cm FOV, 256 x 512 matrix, TR 2200, 90 TE, 5mm slice thickness, 8 ETL and 3 NEX, the scan time would be: A. 2 minutes 11 seconds B. 3 minutes 31 seconds C. 3 minutes 52 seconds D. 4 minutes 8 seconds

B TR x phase matrix x NEX / ETL then / 1000 2200 x 256 x 3 / 8 =211,200 / 1000 = 211.2 sec / 60= 3.52 min 60 x 3=180. + 31= 211

2D acquisitions usually require: A. Flow compensation B. Presaturation slabs C. Fat suppression D. An interslice gap

45: Which of the following echo train lengths generates images in the shortest amount of time? A. 3 ETL B. 6 ETL C. 12 ETL D. 16 ETL

A Free Induction Decay (FID) is produced from a: A. Flip angle B. Shim coil eddy current C. Image archive data cleanse D. RF pulse

A Wilms' tumor can be found: A. On the spine B. On the brainstem C. In the lower extremity D. In a pediatric kidney

A condition called ___________ is a condition in which the spinal cord is pulled lower than its natural position and is generally found in children or patients with Chiari Malformation. A. Cord compression B. Ruptured cord C. Cordial effect D. Tethered cord

Contrast enhanced MRA differs from TOF (time of flight) MRA because: A. Image contrast does not depend on the inflow phenomenon B. Image contrast relies upon T1 shortening of blood following contrast injection C. Timing the start of the sequence relative to the bolus injection is critical D. All of the above

High amplitude signals are stored in the: A. Outer edges of k-space B. Bottom line of k-space C. Top line of k-space D. Center portion of k-space

How do the vertebral arteries enter the cranium? A. External auditory meatus B. Infraorbital sinus C. Cavernous sinus D. Foramen magnum

If a brain exam is being performed and the request is made to evaluate cranial nerves VII and VIII due to the patient's symptoms of tinnitus, a protocol with thin cuts through the ____________ should be performed. A. Sinuses B. Orbits/Optic nerves C. Pituitary gland D. Internal Auditory Canals

If a sequence with a matrix of 256 x 512 is adjusted to 512 x 512, A. The SNR will stay the same B. The scan time will decrease C. The SNR will increase and the scan time will decrease D. The SNR will decrease and the scan time will increase

Immediately following the application of the 90° RF pulse, the precessing protons: A. Begin to precess in phase B. Tip into the transverse plane C. All move into a high energy state D. Both A and B

In DWI sequences, ADC stands for: A. Analog to Digital Converter B. Amazing Dephasing Contrast C. Amplitude Demagnetization Coercion D. Apparent Diffusion Co-efficient

In a Fast Spin Echo sequence, the effective TE are the echoes that are encoded: A. In the first portion of the sequence B. In the outer edges of k-space C. With a high amplitude phase encoding gradient D. With a low amplitude phase encoding gradient

In a contrast enhanced MR angiography of the abdominal arteries, the IV gadolinium would enhance in which order? A. Inferior mesenteric, superior mesenteric, renal, celiac B. Superior mesenterice, inferior mesenteric, celiac, renal C. Celiac, superior mesenteric, inferior mesenteric, renal D. Celiac, superior mesenteric, renal, inferior mesenteric

In a cross sectional view of the MR magnet design, which coils are closest to the patient? A. Active shim coils B. Passive shim coils C. Gradient coils D. Radiofrequency coils

The ________ is a small vein whose function is to drain the posterior abdominal and thoracic wall. A. Inferior mesenteric vein B. Inferior vena cava C. Portal vein D. Azygos vein

The __________ of blood is responsible for the bright blood signal in time of flight MR angiography. A. Long T1 relaxation time B. Short T2 relaxation time C. Density D. Flow

The ___________ supplies blood to the posterior brain. A. Iliac artery B. Internal carotid artery C. External carotid artery D. Vertebro-basilar artery

The ____________ is the largest organ in the abdominal cavity. A. Spleen B. Pancreas C. Stomach D. Liver

The _____________ imaging plane would be the most optimal slice orientation for evaluation of Arnold Chiari Malformation and its inferior cerebellar tonsillar herniation. A. Axial B. Coronal C. RAO D. Sagittal

The __________________ runs the length of the falx cerebri. A. Frontal sinus B. Transverse sinus C. Sigmoid sinus D. Superior sagittal sinus

The cauda equina and the conus medullaris are best seen with a: A. Coronal image of the lumbar spine B. Sagittal image of the cervical spine C. Sagittal image of the thoracic spine D. Sagittal image of the lumbar spine

The central lines of k-space are associated with _____________ in a fast spin echo sequence. A. The echo train length B. Echo time C. Spatial resolution D. Contrast information

The echoes collected from a 256/256 Sagittal Cervical spine have a frequency range 14.1 kHz above and below the central frequency, 1.5Tesla system with 220 Hz chemical shift between fat and water, the vertebral body signal will shift _____ pixels relative to the signal in intervertebral disk. A. 0.8 B. 1.2 C. 1.8 D. 2.0 E. 2.8

The fringe magnetic field: A. Is eliminated by magnetic shielding B. Is eliminated by shimming C. Poses no safety risks if the MRI machine is not scanning D. Can cause nearby medical devices to malfunction

The presaturation pulses typically are found: A. Between the 90º and the 180º pulses B. Prior to the TE C. Following the 180º pulse D. Prior to the excitation pulse E. A and D only

What artery causes flow artifact when imaging the knee? A. Iliac B. Vertebral C. Femoral D. Popliteal

What is defined as the innermost lining of the uterus? A. Myometrium B. Fornix C. Cervix D. Endometrium

What is the daily/weekly QA/QC indicator testing for the accuracy of the magnetic field in determining coil tuning and consistent magnetic field strength? A. Transmit gain B. # of spokes C. NSA D. Center frequency

What is the objective to screening the patient before an MRI exam? A. Obtain pertinent medical history B. Rule out potentially hazardous metallic materials in/on the patient C. Prepare the patient for the procedure/reduce anxiety D. All of the above

What scan plane would be optimal for visualization of the hippocampus? A. Axial B. Sagittal C. Coronal D. Coronal oblique

When going from a linear coil to a quadrature coil: A. Available FOV is reduced B. Parallel imaging is eliminated C. SNR is decreased by 40% D. SNR is increased by 40%

When imaging a hemorrhagic infarct in the brain, which pulse sequence would demonstrate the magnetic susceptibility effects better? A. Spin echo B. Inversion recovery C. Fast spin echo D. Gradient echo

When performing a gradient echo pulse sequence, what is used to refocus the protons and create the echo? A. A focus group B. Shim coils C. RF coils D. Gradient coils

When performing an MRI to confirm a suspected pituitary microadenoma, contrast is injected and imaging is performed: A. With fat suppression to better visualize the lesion-gland contrast B. With delayed imaging because lesions enhance slower than the pituitary gland C. Rapidly because lesions enhance before the pituitary gland D. Rapidly because lesions appear as low signal intensity compared to the enhanced pituitary gland

When performing lumbar spine images through the intervertebral disc spaces, slices oriented in the _______ plane would be selected. A. Axial B. Sagittal C. Coronal D. Oblique

Which of the following implants would be considered acceptable for an MRI scan at 1.5Tesla? A. Swan Ganz catheters B. Neurostimulators C. Non MR conditional cardiac pacemakers D. Heart valves E. Ferrous cerebral aneurysm clips

Which of the following is NOT a magnetic field associated with MR imaging? A. Static magnetic fields B. Oscillating magnetic fields (RF) C. Time varying magnetic fields (gradient) D. Gravitational earth magnetic fields

Which of the following is short for 3 times/daily? A. bid B. kid C. qid D. tid

_________ coined the word "electricity" and was the first to realize that the Earth was a giant magnet. A. Sir Joseph Larmor B. Nikola Tesla C. Michael Faraday D. William Gilbert E. James Clerk Maxwell

_________ would be used to contain the RF in an MR magnet room. A. Steel B. Lead C. Aluminum D. Copper

__________ is defined as a small change in the magnetic field along a particular axis. A. Analog to digital converter B. K-space C. Fourier transform D. A gradient

___________ is professional negligence by act or omission by a health care provider in which the treatment provided falls below the accepted standard of practice in the medical community and causes injury or death to the patient A. Res Ipsa Loquitur B. Respondeat Superior C. Tort D. Malpractice

___________ substances have strong magnetic properties and can be pulled into the magnetic field. A. Wooden B. Paramagnetic C. Diamagnetic D. Ferromagnetic

n what orientation would a tear of the collateral ligaments of the knee be best visualized? A. Perpendicular to the popliteal artery B. Axial C. Sagittal D. Coronal

On a T2 weighted image, edema appears bright because it has a _________ relaxation time. A. Short T1 B. Short T2 C. Long T1 D. Long T2

D; On a T2 weighted image, edema appears bright because fluid has a long T2 relaxation time.

Calculate the scan time for a fast spin echo sequence with the following parameters: TR 2000, TE 30, 192 x 224 matrix, 3 NEX, 4 mm slice thickness, 6 ETL. A. 1 min 9.2 sec B. 2 min 34 sec C. 3 min 2 sec D. 3 min 12 sec E. 3 min 20 sec

D; TR x Phase matrix (smaller #) x NEX / ETL =milliseconds Divide by 1000 to put in seconds

Calculate the scan time for a fast spin echo sequence with the following parameters: TR 3000, TE 100, 512 x 512 matrix, 2 NEX, 5 mm slice thickness, 18 ETL. A. 1 min 46 sec B. 1 min 59 sec C. 2 min 36 sec D. 2 min 51 sec E. 3 min 34 sec

D; TR x Phase matrix (smaller #) x NEX / ETL =milliseconds Divide by 1000 to put in seconds

Contraindications for IV gadolinium contrast use are: A. Pregnant or nursing mothers B. Sickle cell anemia C. Insulin dependent diabetes D. All of the above E. None of the above

During a quench, patients and employees should be evacuated from the scan room to prevent __________. A. Ruptured tympanic membranes B. Frostbite and asphyxiation C. Subdural hematoma D. All of the above E. A and B

FA is short for: A. Fractional anisotrophy B. Fourier analog C. Flip angle D. Fractional acquisition E. A or C

ETL has a__________ relationship between SNR & time? Indirect or Direct

Indirect ; increased ETL = decreased SNR but decreases scan time

Phase Matrix has a__________ relationship between SNR & time? Indirect or Direct

Indirect ; increased PM= decreased SNR & increased time

RBW has a__________ relationship between SNR & time? Indirect or Direct

Indirect ; increased RBW = decreased SNR and time

TE has a__________ relationship between SNR & time? Indirect or Direct

Indirect ; increased TE= increased time but decreased SNR

In the 1930s ______detected and measured single states of rotations of atoms and molecules, determining the magnetic moments of the nuclei

Isidro Isaac Rabi

Hypointense

Low intensity = dark

Inversion Recovery

MR sequence that begins with 180o RF inverting pulse followed by 90o RF excitation pulse, then 180o RF refocusing pulse

Image Reconstruction

Mathematical computation converting the collected raw data signals into images using Fourier Transform

Pixel

Picture element, two-dimensional

_____ developed equation showing precision of nuclear spins being proportional to magnetic field strength

Sir Joseph Larmor

Echo Time (TE)

The time between the excitation pulse of a sequence and the resulting echo used as the MR signal

What is gradient rise time? What is this measured in ?

The time it takes for the gradient to reach its full amplitude. Measured in microseconds mT/M (Millitesla per meter or g/cm (Gauss per centimeter) 10mT/m = 1G/cm

The duty cycle is defined as

The time the gradients are on during a TR period or "working time"

Duty cycle

The time which the gradient system can be run at maximum power

A condition called______ is a condition in which the spinal cord is pulled lower than its natural position and is generally found in children or parents with Chiari Malformation

Tethered cord

Gradient amplitude is defined as

The strength of the gradient

Kienbock's disease is a condition of osteomalacia in the __________. A. Talus bone of the ankle B. Acromion of the shoulder C. Lunate bone of the wrist D. Patella bone of the knee

An indication for injecting a patient with Gad contrast for an MRI lumbar spine would be

Prior/ previous surgery

During a post surgical MRI of the lumbar spine, the evaluation of post operative surgical regions and/or the possibility of scar tissue can be best accomplished by

Sagittal slice/ T1 weighted post gadolinium

Which gradient alters the magnetic field in each plane?

Sagittal= X Coronal=Y Transverse= Z

Factors that affect duty cycle

# of slices Fat suppression pulses Presat slabs/bands Increase ETL

Transmitter

the segment of the MR scanner that produces the RF current and delivers it to the transmitting coil (antenna)

Slice thickness

the thickness of an imaging slice

Repetition time

the time between successive pulse sequences applied to the same slice, the time between consecutive 90o RF excitation pulses. TR is the controlling factor of T1 contrast, and a factor in MR scan time

Gating

timing the collection of MR data to physiological motion in order to minimize motion artifacts, as in cardiac gating or respiratory gating

Coherent

maintaining a constant state of "in-phase" relationships between protons; located at the same phase cycle simultaneously

Effective TR

referring to prospective cardiac triggering techniques, the patient's heart rate controls the TR, or termed the effective or available TR (TReff), according to the beats per minute (BPM) factor

Dynamic Contrast Enhancement

refers to DCE, or Basic T1 perfusion imaging (pituitary or prostate dynamic sequences, longer acquisition times/dynamic compared to DSC)

Dynamic Susceptibility Contrast

refers to DSC, or better known as T2 gradient echo Perfusion imaging, utilized in Brain Perfusion studies

see Echo Time

see Inversion Time

In _____, Damadian and his team constructed the first super conducting NMR scanner and produced the first image of the human thorax which took almost 5 hours

1977

In the year______, schering's _____IV gad contrast gets the first approval by the FDA.

1988; Magnevist

Functional MRI (fMRI) was developed in

1991

SAR(specific absorption rate) is proportional to the power of _____ for the resonance frequency.

2; doubling field strength results in fourfold increase in SAR potential.

A _________ can mean something that is a hindrance or puts an individual or group at a disadvantage, or something that someone is responsible for, or something that increases the chance of something occurring. A. Liability B. Statutory law C. Res Ipsa Loquitur D. Tort

A ______________ is defined as a picture element and has _________ characteristics. A. Pixel, two-dimensional B. Pixel, three-dimensional C. Voxel, two-dimensional D. Voxel, three-dimensional

A fast spin echo sequence is faster than a conventional spin echo pulse sequence because: A. Several echoes for each slice are collected during each TR period B. T2* contrast takes less time C. A shorter TR is used for fast spin echo D. A smaller pixel size is utilized

A major advantage of a 3D time of flight over a 2D time of flight sequence is the ability to: A. Visualize smaller vessels B. Shorten the image time by two-thirds C. Reduce the signal from stationary background tissue D. Determine and measure blood flow velocities

A pulse sequence that begins with a 180° RF pulse, followed by a 90° RF excitation pulse, would be a(n): A. Inversion recovery B. Spin echo C. Gradient echo D. Dual echo spin echo

A technique that reduces scan time by not filling as many lines of k-space in the phase direction, while maintaining spatial resolution, is known as: A. Rectangular FOV B. Parallel imaging C. Partial saturation D. Dual inversion recovery

A technique utilized to reduce the MRI scan time which requires the use of an array coil is: A. Parallel imaging B. 1/2 NEX C. Rectangular field of view D. Phase encoding reduction technique

All of the following arise from the aorta EXCEPT? A. Right vertebral artery B. Left subclavian artery C. Left common carotid artery D. Brachiocephalic artery

How many radiofrequency pulses produce a FID? A. 1 B. 2 C. 3 D. None

If a brain exam is being perfomed and the request is made to rule out globe tumor due to symptoms of diplopia, a protocol with thin cuts through the ____________ should be performed A. Orbits/Optic Nerves B. Internal auditory canals C. Pituitary gland D. Cerebellar Tonsils

If a patient has metal hardware from previous spinal surgery, the ___________ sequence should be avoided due to prominence of susceptibility artifacts. A. Gradient echo B. Spin echo C. Inversion recovery D. Fast spin echo

If a sagittal slice plane has been selected, the __________ is enabled to alter the magnetic field around the patient's body. A. X gradient B. Y gradient C. Z gradient D. Shim coils

If the RF energy transmitted is __ MHz, the slice through the patient would be in a magnetic field of .995T. A. 42.36 B. 42.57 C. 63.86 D. 95.5

In one T2 relaxation time: A. 63% of the transverse magnetization has decayed B. 63% of the longitudinal magnetization has decayed C. 37% of the longitudinal magnetization has decayed D. None of the above

In order to acquire an intracranial arterial blood flow sequence , a presaturation pulse would be applied in which location? A. Superior to slice group B. Inferior to slice group C. Anterior brain D. Below the heart

Increasing the field of view (FOV) would have what effect? A. Decrease spatial resolution B. Increase spatial resolution C. Decrease temporal resolution D. Increase temporal resolution

SSFP is an abbreviation for: A. Steady state free precession B. Single shot fourier perfusion C. Somato sensory free potential D. Signal sensing fat progression

Short TR and Short TE exhibit which type of contrast A. T1 B T2 C Proton Density D IR

TE is short for: A. Echo Time B. Time of Excellence C. T1 Exponential D. T2 Education

The MRA technique that relies on velocity induced phase shifts to distinguish between moving and stationary protons is: A. Phase contrast B. CE-MRA C. Time of flight D. Time resolved

The ______________ is the speed rate of ascent or descent of a gradient from zero to its maximum amplitude, either positive or negative A. Slew rate B. Rise time C. Duty cycle D. Fringe field

The brainstem includes all of the following EXCEPT: A. Putamen B. Mid brain C. Pons D. Medulla oblongata

The dural venous sinuses that drain into the internal jugular vein are the: A. Sigmoid sinus B. Superior sagittal sinus C. Inferior sagittal sinus D. Transverse sinus

The first documented human MR image was obtained on a 15 MHz RF system, what field strength did it operate at? A. 0.352 Tesla B. 0.714 Tesla C. 1.264 Tesla D. 1.503 Tesla

The gradient rise time is defined as the: A. Time it takes for the gradient to reach its full amplitude B. Time it takes longitudinal magnetization to regrow C. Time between TI and initial RF pulse D. Speed rate of ascent or descent of a gradient from zero to its maximum amplitude

The liquid cryogens most often used to maintain field strength in a super conducting MR system are: A. Helium B. Gadolinium C. Hydrogen D. Molybdenum

The primary biological effect of radiofrequency fields is: A. Tissue heating B. Asphyxiation C. Hyperthermia D. None of the above

The purpose of shimming the magnet is to: A. make the B0 field as homogenous as possible B. make the B1 field as homogenous as possible C. make the scan time as short as possible D. correct for gradient slopes

The range of transmitted frequencies at each slice position must _____ to maintain slice thickness. A. Remain constant B. Increase with each slice C. Decrease with each slice D. Disable, then re-enable

The right and left optic nerve join at the: A. Optic chiasm B. Foramen magnum C. Transverse sinus D. Internal optic canals

The strength of the gradient over a specific distance is known as the: A. Slew rate B. Rise time C. Duty cycle D. Flux lines

The substances that bind to gadolinium ions are defined as: A. Chelates B. Relaxivities C. Pathogens D. Echo trains

The time during which the frequency encoding gradient is on: A. Increases with a reduction in receiver bandwidth B. Decreases with a reduction in receiver bandwidth C. Is not affected by a reduction in receiver bandwidth D. Is limited by the inverse of the gradient slew rate

To best visualize the pituitary gland in MRI, high resolution T1 weighted images in the __________ planes pre and post contrast are optimal. A. Sagittal and Coronal B. Axial and Coronal C. Axial and Sagittal D. Coronal and Trendelenberg

To create a projection image in MRA, the technique most commonly used is: A. MIP B. MPR C. ADC D. DIEP

Utilization of surface coils yields all of the following EXCEPT: A. Increased FOV capabilty B. Localized, smaller FOV capability C. Increased SNR D. Smaller slice thickness

What is a spin echo? A. 90° RF followed by 180° RF B. 90° RF followed by train of 180° RF pulses C. 180° RF followed by 90°RF D. variable° RF followed by gradient to produce echo

What is the TR range for a T1 contrast weighted image ? A 350-700ms B. 1600- 4000ms C. 2000- 6000ms D 80 - 120ms

When imaging the shoulder, the coronal oblique scan plane is oriented parallel to the supraspinatus muscle and perpendicular to the glenoid fossa. A. True B. False

When thermal equilibrium is reached: A. There are more hydrogen protons in the low energy state B. There are more hydrogen protons in the high energy state C. The low and high energy protons completely cancel each other out D. The flip angle nears the Ernst angle for optimal signal

When utilizing time-of-flight (TOF) MRA to evaluate peripheral vascular flow, such as arterial blood flow in the legs, presaturation pulses are: A. Positioned inferior to the slice group B. Positioned posterior to the dorsalis pedis C. Positioned superior to the slice group D. Not utilized

Which cranial nerve is responsible for Bell's Palsy? A. Cranial nerve VII (the facial nerve) B. Cranial nerve VIII (vestibulocochlear nerve) C. Cranial nerve XII (hypoglossal nerve) D. Cranial nerve X (vagus nerve)

Which factors controls the amount of T1 weighting in an image? A. TR B. TE C. Flip angle D. NEX

Which imaging plane would best display both the dorsal and ventral nerve roots? A. Axial B. Sagittal C. Coronal D. All of the avove

Which is the optimal imaging plane for visualization of the pancreas? A. Axial B. Sagittal C. Coronal D. Parallel to malleoli

Which nerve is responsible for carpal tunnel syndrome? A. Median nerve B. Ulnar nerve C. Radial nerve D. Tarsal tunnel peroneal nerve

Which of the following echo train lengths generate a set of images with the greatest signal-to-noise, assuming all other parameters are the same? A. 3 ETL B. 6 ETL C. 12 ETL D. 16 ETL

Which of the following has been documented to cause muscle contractions, cardiac arrhythmias, mild cutaneous sensations and visual light flashes? A. Time varying magnetic fields (gradient) B. Static magnetic fields C. Oscillating magnetic fields (radiofrequency)

Which tendon is torn most often in a rotator cuff injury? A. Supraspinatus B. Infraspinatus C. Teres minor D. Subscapularis

________ conceived the idea of echo planar imaging, which can rapidly scan the whole brain. He and his colleagues publish the first successful MRI of a living human body part - a finger A. Peter Mansfield B. Raymond Damadian C. Michael Faraday D. Sir Joseph Larmor

__________ is defined as "the thing speaks for itself", or, a doctrine or legal ruling that permits the presumption that a defendant was negligent even without direct evidence of how any defendant behaved. A. Res Ipsa Loquitur B. Respondeat Superior C. Tort D. Statutory law

___________ discovered that tumors and normal tissue can be distinguished by NMR because of their relaxation times. A. Damadian B. Lauterbur C. Bloch D. Larmor

____________ can be described as water molecules moving in a preferred direction. A. Anisotropic diffusion B. Isotropic diffusion C. Anisotropic voxel D. Isotropic voxel

____________ is used as an anti-peristalsis agent in MR Enterography procedures. A. Glucagon B. Barium C. Gadolinium D. Immodium

_____________ is the most important aspect of providing a safe MR environment. A. Education B. Shielding C. Shimming D. Screening

______________ is the term used to describe the degree of magnetization of an object. A. Susceptibility B. Fourier transform C. Radiofrequency D. Gradient

Receiver coil

A coil, or antenna used to detect the NMR signal. Types of receiver coils include solenoid, quadrature and phased array coils

Steady state free precession

A gradient echo sequence in which a non-zero steady state develops for both transverse and longitudinal components of magnetization

Parallel Imaging

A scan time acceleration technique which requires the use of a phased array coil to reconstruct an image in less time than conventional imaging

Pulse Sequence

A set of specifically timed pulses and/or magnetic field gradients producing an image with specific characteristics based on the timing and duration of the pulses programmed

Dixon

A technique utilizing the differences in resonant frequencies of fat and water separating the two tissues, acquiring each separately, then adding the two to yield a water-only image (fat suppression), then subtracting the two to yield a fat-only image

All of the following affect acquisition time EXCEPT: A. TR B. TE C. NEX D. Matrix

All of the following are ferromagnetic substances EXCEPT: A. Stainless Steel B. Gold C. Iron D. Nickel

All of the following are types of inversion recovery sequences EXCEPT: A. STIR B. DWI C. FLAIR D. 3D-IR

All of the following join to form the hepatic portal vein EXCEPT: A. Splenic vein B. Inferior vena cava C. Superior mesenteric vein D. Cystic vein E. Inferior mesenteric vein

All of the following structures are seen on MRCP EXCEPT: A. Gallbladder B. Liver C. Bile duct D. Pancreatic duct

All of the following yield a higher signal-to-noise ratio EXCEPT: A. Increase TR B. Increase TE C. Larger FOV D. Higher NEX E. Decrease Matrix

An abbreviation for a Latin word that means nothing by mouth? A. PO B. NPO C. QID D. CPR

Another name for a picture element is a: A. Voxel B. Pixel C. Cubicle D. Filament

Applying two gradients simultaneously during slice selection would: A. Produce an artifact B. Produce an oblique slice C. Produce partial volume averaging D. Result in an equipment fault

As the flip angle is increased, SNR(signal to noise ratio): A. Decreases until it reaches the Ernst angle B. Increases to a point called the Ernst angle C. Reduces to the Minimum Allowable Tesla (MAT) D. Is unaffected

As the number of excitations (NEX) is increased from 1 to 3, which of the following does NOT occur? A. The scan time triples B. The pixel size is increased C. The image resolution remains the same D. The signal-to-noise ratio is increased

FDA limits for whole body SAR is ______ over 15 minutes of scanning. A. 2 W/kg B. 4 W/kg C. 6 W/kg D. 8 W/kg

Fast spin echo sequences are fast because: A. The TE used is very short B. More than 1 line of k-space is acquired in each TR period C. No 180º refocusing pulses are used D. The excitation flip angle is very small

Following the administration of IV gadolinium contrast, it is recommended to: A. Follow the injection with a flush of 0.5 mL saline B. Follow the injection with a flush of 5 mL saline C. Follow the injection with a flush of 100 mL saline D. Follow the injection with a flush of Volumen

For optimal cervical spine patient positioning, optimal patient orientation should be ____________ and the coil should be positioned __________ between the levels C1-C7. A. Supine; anterior to patient B. Supine; posterior to patient C. Prone; anterior to patient D. Prone; posterior to patient

Gadolinium IV contrast: A. Lengthens the T1 and T2 times of tissues B. Shortens the T1 and T2 times of tissues C. Does not affect the T1 and/or T2 times of tissues D. Only shortens the T2 times of tissues

Hemosiderin appears ______________ to surrounding tissues on T2 weighted images. A. Hyperintense B. Hypointense C. Isointense D. Nondescript

How does Gadolinium function as a contrast agent? A. It is a direct image component, resonating at the same frequency as water B. It shortens the T1 time of tissue C. It lengthens the T2 time of tissues D. It emits radiofrequency that is picked up by the receiver coil

How well a material attracts the imaginary lines of the magnetic field is defined as: A. Magnetic susceptibility B. Magnetic permeability C. Magnetohydrodynamic effect D. Magnetic resonance

Hydrogen is used in MR imaging because: A. It has an even atomic mass number B. Of its abundance in the body C. Of its detectability in the presence of ionizing radiation D. None of the above

Slew rate

is the speed rate of ascent or descent of a gradient from zero to its maximum amplitude, either positive or negative

As the number of phase encodings is increased from 256 to 512, SNR (signal to noise ratio): A. Increases B. Decreases C. Doubles D. Is unchanged

Creating additional images in various planes from a 3D data set is accomplished by a technique known as: A. Maximum intensity projection (MIP) B. Multi-Planar reconstruction (MPR) C. Region of interest calculation(ROI) D. Subtraction

Decreasing the receiver bandwidth (utilizing a narrow BW): A. Increases the number of slices available B. Decreases the number of slices available C. Does not change the number of slices available D. Decreases SNR E. A and D only F. B and D only

Decreasing the slice selection gradient strength will ________ of the resulting slice. A. Change the orientation B. Change the slice thickness C. Invert the phase and frequency sampling directions D. Alter the field of view

If 24 4mm slices are planned with a gap of 1mm, the total anatomic coverage is _______ cm. A. 10 B. 12 C. 15 D. 120

If a coronal slice plane has been selected, the __________ is enabled to alter the magnetic field around the patient's body. A. X gradient B. Y gradient C. Z gradient D. Shim coils

If the receiver bandwidth (rBW) is decreased, the sampling rate: A. Increases B. Decreases C. Increases by the square root of 2 D. Does not change

If the repetition time is doubled, the scan time will: A. Be 40% greater B. Double C. Be half of what it was D. Triple

In 1975, ___________ introduced 2D NMR using phase and frequency encoding, and the Fourier Transform A. Raymond Damadian B. Richard Ernst C. Joseph Larmor D. Felix Bloch

In a fast spin echo pulse sequence, if the TSE factor (echo train length) is increased by a factor of 3, the scan time will be: A. Twice as fast B. Three times faster C. Six times faster D. Nine times as fast

In an inversion recovery sequence, the time interval between the 180° RF pulse and the 90° RF pulse is the: A. TR B. TI C. TE D. 3T

In emergency situations, a physician can order a procedure under ____________ if the benefits outweigh the risks, in reference to an unconscious patient, for example. A. Res Ipsa Loquitur B. Implied consent C. Informed consent D. Statutory law

In order for energy to be efficiently transferred between a transmitter and receiver, the two must be at the same: A. Charge B. Frequency C. Spin density D. Eye level

In order to acquire an intracranial venogram, a MR angiographic sequence would have a presaturation pulse applied in which location? A. Superior to slice group B. Inferior to slice group C. Anterior brain D. Posterior brain

In the TMJ's, the articular disc lies between what two anatomical structures? A. Acetabulum and mandibular condyle B. Mandibular fossa and mandibular condyle C. Pudendal nerve and mandibular condyle D. External auditory meatus and mandibular condyle

In time-of-flight (TOF) imaging targeted to the subclavian arteries, the two best imaging planes would be: A. Axial and coronal B. Axial and sagittal C. Sagittal and coronal D. Cancel the patient, these don't come out

K-space is typically filled: A. With a funnel B. One line at a time C. From back to front D. From right to left

Law that pertains to private legal rights and matters is defined as: A. Criminal law B. Civil law C. Tort D. Respondeat superior

Limitations in abdominal MRI can include all of the following except: A. Peristalsis B. CSF pulsation C. Irregular or inconsistent breathing D. Long acquisition times

Long TR and Long TE exhibit which type of contrast A. T1 B T2 C Proton Density D IR

MR angiography uses which kind of pulse sequence? A. Spin echo B. Gradient echo C. Inversion recovery D. T2 fat suppression

Passive shielding can be accomplished by lining the MR room with ___________. A. Lead B. Steel C. Copper D. Aluminum

RBW is an abbreviation for: A. Radiofrequency bundled wiring B. Receiver bandwidth C. Retrograde bladder weave D. Radial balanced waveform

Reducing the slice thickness will result in: A. An increase in partial volume averaging B. A decrease in SNR C. An increase in SNR D. A & B only E. None of the above

Risk factors of MR exposure with regards to SAR absorption include all of the following EXCEPT: A. Cardiovascular disease B. Hypotension C. Obesity D. Geriatric patients

The _________ is defined as the resonant frequency, and is equal to the product of the magnetic field and the gyromagnetic ratio. A. RF excitation pulse B. Precessional frequency C. Inversion recovery D. Presaturation pulse

The ___________ supplies blood to the anterior brain. A. Iliac artery B. Internal carotid artery C. External carotid artery D. Vertebro-basilar artery

The array processor is responsible for: A. Shimming the magnetic field B. Reconstructing the images using the Fourier transform C. Increasing scan speed using parallel coil elements D. Calculating Field of View measurements inside surface coils

The best view to visualize the epiglottis and the base of the tongue would be: A. Axial B. Sagittal C. Coronal D. None of the above

A magnetic vector possesses attributes of both __________ and _____________. A. Strength; magnitude B. Direction; purpose C. Magnitude; direction D. Strength; flow

An imaging option used to compensate for CSF flow in the cerivcal spine would be

Gradient moment nulling

The common carotid artery bifurcates into the internal and external carotid artery at the level of the: A. C1-2 disc space B. C3-4 disc space C. C6-7 disc space D. T2-3 disc space

The common carotid artery bifurcates into the internal and external carotid at the level of C5-6. A. True B. False

The degree of stenosis ___________ with time-of-flight MRA. A. Will always be underestimated B. May be overestimated C. Will always be accurately depicted D. Cannot be visualized

The direction of the magnet in a superconducting magnetic is A. Elliptical B. Horizontal C. Vertical D. None of the above

Calculate the pixel area for the following sequence: TR 450, TE 12, FOV 18cm, 224 x 256 matrix, 4 NEX. A. 0.56 mm2 B. 0.70 mm2 C. 0.80 mm2 D. 1.50 mm2

A Phase X Freq 18 x 10= 180mm .80 (180/224) x .70( =180/256) = .56

Isocenter

A location within the magnet bore assigned coordinates X0, Y0, Z0, and having magnetic field strength B0 and center frequency relative to field strength

Permanent magnet

A magnet designed with blocks of ferromagnetic materials to generate a magnetic field, typically heavy in construction. No supercooling or additional electrical power required, typically low field

Superconducting magnet

A magnet whose field is generated by current in wires made of a superconducting material, and is cooled with cryogens. Typically high field systems with horizontal field orientation

Gadolinium

A non toxic paramagnetic contrast agent used in MR imaging. The infusion of gadolinium based paramagnetic contrast agents (GBCA's) shortens the T1 (and T2) times of tissue, dependent upon concentration

Isotope

Atomic nuclei that contain the same number of protons but differ in the number of neutrons in the nucleus of the atom

Which imaging plane would best display both dorsal and ventral nerve roots

Axial

A 2D TOF MRA sequence would be selected to cover _________. A. A small localized region of interest B. A large area of vascular coverage C. Only the common carotid bifurcation D. The ducts of the biliary tree

A 6 inch surface coil is able to receive signal: A. 6 inches deep into the patient B. 3 inches deep into the patient C. 2 inches deep into the patient D. 1 inch deep into the patient

A FID is produced from: A. A gradient B. An RF pulse C. T2 decay D. T1 recovery

A FLAIR sequence with a long TI is utilized to: A. null the signal from fat B. null the signal from CSF C. null the signal from white matter D. enhance the signal from flowing blood

A ___________ is a medical or psychological treatment guideline, and can be general or specific. A. Explanation of benefits B. Standard of care C. WebMD symptom checker D. Tort doctrine E. Nosocomial plan

A disadvantage of TOF MRA is high signal in some background tissues. To minimize signal from background tissues, TE should be selected that enable the signals from fat and water to be: A. In phase B. Out of phase C. Presaturated D. Metabolite detected

A major advantage of a 2D time of flight over a 3D time of flight sequence is the ability to: A. Determine the precise, accurate percentage of stenosis B. Image larger areas without saturation of flowing blood C. Better image retrograde flow D. Complete image acquisition in twice the time

A method of reducing MRI scan time by not filling as many lines of k-space in the phase direction, while maintaining spatial resolution, is known as: A. Halfscan B. Rectangular FOV C. Partial fourier D. Fast spin echo

A more accurate method of detecting small intra-ocular ferrous foreign bodies is: A. Ferromagnetic Detection systems B. Cat Scan C. Finger sweep D. Nuclear stress test

A narrow receiver bandwidth: A. Decreases susceptibility artifact B. Increases susceptibility artifact C. Lowers SNR D. Should be used in the presence of metal implants

A patient presenting with an elevated PSA would have a study with attention to the _________. A. Pituitary gland B. Prostate gland C. Parotid gland D. Thyroid gland

A set of specifically timed instructions to the magnet is known as: A. A recipe B. A pulse sequence C. Gyromagnetic instructor D. Fourier transformation

Active shielding can be defined as: A. Steel lining in the walls of the scanner room B. Superconducting windings within the MR scanner, reducing the fringe magnetic field C. Performing robust prescan measurements for the purpose of field homogeneity D. Monthly adjustments made to the magnetic field for the purpose of field uniformity E. Copper lining in the walls of the scanner room

: The _____________ is the inferior portion of the spinal cord and is found at the ________ disc level. A. Cauda equina; T12-L1 B. Cauda equina; L2-L3 C. Conus medullaris; T12-L1 D. Conus medullaris; L2-L3

A STIR sequence with a TI time of 160 ms will null signal from fat at what field strength? A. 0.5 Tesla B. 1 Tesla C. 1.5 Tesla D. 3 Tesla

A _____________ is a medical or psychological treatment guideline, and specifies appropriate treatment based on scientific evidence and collaboration between medical professionals involved in the treatment of a given condition. A. Res Ipsa Loquitur B. Statutory law C. Standard of care D. Liability

A coil that is not properly tuned to the correct magnetic field strength will result in: A. Patient injury B. FID artifacts C. Signal loss D. Improvements in resolution capabilities

A depression in the base of the skull where the pituitary gland is located is called the ___________. A. Cerebro-pontine angle B. Foramen magnum C. Sella turcica D. Sphenoid sinus

CP coil

Circularly polarized transmission or receiver coil with two orthogonal transmission and/or receiver channels, also known as a quadrature coil. This yields better signal-to-noise than a linear coil

The ______ is the inferior portion of the spinal cord and is found at the ____ disc level

Conus Medullaris; T12-L1

The optimal imaging plane for evaluation of the degree of curvature due to scoliosis would be

Coronal

Calculate the voxel volume for the following pulse sequence: TR 2000, TE 85, FOV 28cm, Matrix 272 x 320, 5mm slice thickness, 3 NSA. A. 0.88 mm3 B. 1.03 mm3 C. 1.91mm3 D. 4.55 mm3

D FOV/ matrix x FOV/matrix = pixel area Pixel area x slice thickness = voxel volume 280/272 x 280/320= .91 0.91 x 5 = 4.55

FOV has a__________ relationship between SNR & time? Indirect or Direct

Direct only for SNR , time is unaffected by FOV

Flip angle has a__________ relationship between SNR & time? Indirect or Direct

Direct only for SNR does not affect time

NEX has a__________ relationship between SNR & time? Indirect or Direct

Direct; increased NEX= increased SNR but increased Time

TR has a__________ relationship between SNR & time? Indirect or Direct

Direct; increased TR = increased SNR and Time

For patients that have undergone surgery for herniated disc in the lumbar spine, gadolinium contrast enhancement can be utilized to distinguish recurrent disc from post operative scar tissue because:

Disc enhances more slowly than post operative scar. Scar tissue enhances shortly after administration and looks hyper intense on T1 weighted, while the disc will enhance 20 minutes after injection.

Echo Spacing

Distance between two echoes, as in Fast Spin Echo or EPI sequences. The shorter the echo spacing, the more compact the sequence timing and few artifacts result

Which area of the brain is typically affected in patients with a history of epilepsy? A. Temporal lobe B. Conus C. Hippocampus D. All of the above E. A and/or C

ADC stands for: A. Anisotropic diode convexity B. Analog to digital converter C. Apparent diffusion coefficient D. Acromion to delta clavicular E. B and/or C

Hydrogen protons in the anti-parallel state are referred to as: A. Spin down B. Low energy spins C. High energy spins D. Both A and B E. Both A and C

Patient types who may require additional monitoring while undergoing an MR exam might include: A. Patients with limited vocal and/or auditory ability B. Critical and/or unresponsive patients C. Pediatric (with or without sedation) D. Claustrophobic patients E. All of the above

Signal to Noise Ratio (SNR) would increase in a 3D volume acquisition with an increase in: A. TE B. Slices C. Field of view D. All of the above E. B and/or C only

The overall signal-to-noise ratio will increase in 3D volume imaging when there is an increase in: A. Number of slices or partitions B. TE C. Phase Matrix D. Field of View E. A and/or D

The strength of the gradient magnetic fields are measured in: A. Gauss per centimeter B. Tesla per echo C. Watts per kilogram D. Millitesla per meter E. A and D

The type of rock upon which magnetism was discovered is called? A. Plutonium B. Magnetite C. Lodestone D. Galactacite E. B and/or C

Transmit gain is a quality measure evaluating for? A. Geometric accuracy -- Z gradient B. Geometric accuracy -- X/Y gradients C. High contrast spatial resolution D. Low contrast spatial resolution E. Accuracy of flip angles

The use of multiple powerful RF pulses is defined as

Fast spin echo. Can lead to increased SAR induction

_______ Discovered that a charged particle, such as a proton, spinning around its own axis, has a magnetic field, known as magnetic momentum

Felix Bloch; both Bloch and Purcell demonstrated the phenomenon known as nuclear magnetic resonance in condensed matter.

If a patient has metal hardware from previous surgeries the _____ sequence should've be avoided due to prominence of susceptibility artifacts?

Gradient echo; due to the lack of 180 degree refocusing pulse. Use less in patient with hardware.

Hyperintense

High intensity= bright

On T2 weighted images of the spine, the CSF appears

Hyper intense (High signal) to the spinal cord

On T1 weighted images of the spine, the CSF appears

Hypo intense (low intensity) to the spinal cord

Echo Train

Multiple echoes in sequence, each obtaining rows of k space, shortening overall scan time, also reducing SNR with each additional echo train

The _____ scan plane best demonstrates the degree of spinal stenosis?

Sagittal

The ideal scan plane in spine imaging for evaluation of the degree of posterior disc hernia Timon as well as intervertebral disc height would be

Sagittal

The cauda equine and the conus medullary are best seen with a

Sagittal image of spine

The ligament I'm flavum can be found in which part of the body?

Spine

Eddy Currents

The electrical currents generated in a conductor by changing magnetic fields or movement of the conductor within the magnetic field

Electromagnetic Induction

The electrical voltage created in a receiver coil as a result of a temporal change in the magnetic field

Specific Absorption Rate (SAR)

The number of Watts of RF energy per kilogram of body weight in an imaging sequence

Shimming

The process of improving the homogeneity of the magnetic field, either through active shimming (use of shim coils) or passive shimming (adding or removing steel from the magnet)

Excitation pulse

The radiofrequency (RF) pulse used to disturb the equilibrium of the Net Magnetization Vector; the higher the energy of excitation, the greater the flipped angle of magnetization

Spin lattice relaxation

The return of the longitudinal magnetization to its equilibrium value along the Z axis (T1 recovery)

Spin spin relaxation

The return of the transverse magnetization to its equilibrium value, zero (T2 decay)

Echo Planar Imaging

Very fast MR imaging technique where the complete image is acquired using a single selective excitation pulse, field gradients are periodically switched to generate a series of gradient echoes

Amplitude

equates to signal height or strength; the larger the amplitude, the larger the number of protons

Active shielding

is a term describing the containment of the static magnetic fringe field through the use of secondary coils attached around the MRI scanner

Active shimming

is a term used to describe the adjustment of the current within the shim coils on a per/patient or per/sequence basis, for the purposes of achieving uniform fat suppression or optimal prescan calibrations. A well shimmed FID is the desired end result of a good active shim calibration

An anisotropic voxel

is a voxel with uneven measurements, with regards to the phase, frequency and slice thickness dimensions

Diamagnetism

is an effect resulting in a slightly weakened magnetic field when a substance is introduced into it. This material is considered to have a negative magnetic susceptibility

The body coil

is an integrated part of the magnet design that acts as its own transceiver coil, with large FOV capabilities, but lacking the high SNR of localized coils

The bvalue

is defined as a factor in diffusion weighted imaging; the higher the factor, the stronger the diffusion weighting

Bandwidth

is defined as the range or spectrum of frequencies (minimum to maximum processed frequency) of a pulse sequence acquired by an RF system

The B0 field

is defined as the static main magnetic field of an MR system

The Analog to digital converter (ADC)

is part of the computer system that converts the analog acquired MR signal into a digital signal

The B1 field

is the alternating magnetic field generated by the RF in a transceiver coil, perpendicular to B0

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