mri review
166 using a conventional spin echo multi slice sequence the number of slices allowed when increasing the TE from 20 to 40 MS Decrease is not affected increases by a factor of TR/TE Doubles
Decrease
162Increasing the number of phase encoding (matrix) from 128 -256 the snr Increases Inverts Is not affected Decreases
Decreases
124As matrix increases, partial volume averaging..
Decreases As fov increases, voxels size increases and pva increases. As slice thickness increases, voxel size increases and pva increases. As matrix increases voxel size decreases and pva decreases Tr does not effect voxel size or pva
133 reducing the TR down to or below T2 Relaxation Of the tissue -Decreases snr -Reduces the contrast based on T2 relaxation times of tissues -Increases saturation effects -A and c
Decreases snr Increases saturation effects
147 decreasing the rBw Decreases the number of slices Inverts number if slices Increases number of slices No effect on slices
Decreases the number of slices
154Increasing the number of phase encoding will produce an image with Increase voxel volume Decreased voxel volume An unchanged voxel volume Higher snr
Decreases voxel volume??????
94A patient with apraxia will have difficulty with Speaking balance dressing swallowing
Dressing apraxia can occur after a brain injury such as a stroke. apraxia is the inability to performed learned motor skills. these patient understand direction but unable to complete a task such as getting dressing.
95A patient with aphasia will have difficulty with all the following except Speaking reading dressing swallowing
Dressing aphasia can occur after brain injury such as a stroke. aphasia i the inability to complete language tasks such as speaking, reading and writing. these patients may have receptive aphasia (wherein they can understand what is being said but cannot respond appropriately.) in addition, aphasic can have difficulty swallowing
187TVMF effects are of greater concern of which scan sequences FSE EPI GE SE
EPI
193 the image and sequence that is most concerned for time varying magnetic field affect is Spin echo gradient echo fast spin echo echo planar
Echo planar echo planar imaging use gradients with very rapid rise times because all of the K space is filled in one TR time by changing the amplitude of the gradient as many as 123, 256, 512 times per TR
80 the high frequency (low amplitude) data points in k space provide
Edge detail (spatial resolution)
29Gradient echo sequences acquired for high signal from fluid are known as all of the following except Coherent gradient echoes Incoherent gradient echoes Steady state gradients echoes T2* gradient echoes
Incoherent gradient echo
39 The pt who has too much insulin in their body is experiencing A diabetic come B hyperglycemia C Hypoglycemia D hypovolemia
Hypoglycemia
76The diabetic patient who has excessive insulin in their body is said to have Hypotension Hyperglycemia Hypoglycemia Hyperkalemia
Hypoglycemia hypoglycemia i a condition whereby the diabetic patient does not have enough sugar in the system for the insulin delivered to metabolize. a diabetic patient who doe not have enough insulin and has too much sugar in the body would experience hyperglycemia
18The components that make up the diencephalon include
Hypothalamus, hyperthalamus and right and left thalamus
30Dynamic enhanced mra of the renal arteries are performed with the use of
Incoherent gradient echo
170 the effective TE in a fast spin echo pulse sequence determines the Image contrast Scan time Spatial resolution Number of frequency samples.
Image contrast
114 Each frame of a cardiac cine sequences displays the heart: In various images planes With varying degrees of spatial resolution From a slightly different viewpoints In different phases of the cardiac cycle
In different phases of the cardiac cycle
94 the MR signal is produced by magnetization: Out of phase In the longitudinal direction Decayed In transverse plane
In transverse plane When the precessing net magnification passed through the receiver coil, it induces a signal in the coil (faradays law of induction)
122 as fov increases partial volume averaging Increases Decreases Stays the same Is not affected
Increases
161 increasing slice thickness from 5 to 10 Snr Increases by a factor of 2 Increases by a factor of 4 Is not affected Decreases by a factor of 2
Increases by a factor of 2
132If the slice thickness is increased by a factor of 2 (from 5 to 10 mm thickness) the snr Increases by square root of two Increases by a factor of 2 Reduces by a factor of 2 Reduces by a factor of the square root of 2
Increases by a factor of 2??????
165 using a conventional spin echo multi slice sequence the number of slices allowed with increasing the TR Decrease is not affected increases by a factor of TR/TE Doubles
Increases by a factor of TR/TE
145 decreasing receive bandwidth Increases readout time Inverts read out time Reduces readout time No effect on readout
Increases readout time
149The time during which frequency encoding is on Increases with a reduction in rBW Decreases with a reduction in rBW Not affected with a reduction in rBW Cannot be changed
Increases with reduction in rBW reducing rBW increases freq encoding
93A major advantage of MRA over conventional angiography is that
Multiple views can be produced from a single acquisition
88 Cardiac analysis performed with a technique using SAT bands to assess wall motion is known as Myocardial tagging Four chamber imaging Short axis imaging Cardic gating
Myocardial tagging
51 during thermal equilibrium the vector that represents the spin excess is known as the
NMV
157Magnetic field shielding can be achieved either actively or passively. Passive shielding can be achieved by lining the MRI room with Copper steel lead none of the above
copper
pg 59 the equation dB/dt=dv define :
faradays law of induction dB- a voltage magnetic field dt - a change in time dV - a change in voltage
61 a single shot FSE sequence is acquired when #PEs = 256 and ETL = 256 #PEs = 128 and ETL = 256 #PEs = 256 and ETL = 128 #PEs = 256 and ETL = 64
#PEs = 256 and ETL = 256 #PEs = 128 and ETL = 256 #PEs = 256 and ETL = 128 #PEs = 256 and ETL = 64
60 the number of shots is calculated by
#PEs/ETL
33The amount of time that a gradients is permitted to work is known as the duty cycle and is measured in units of mT/M G/cm T/m/s Us %
%
118Standard dose for gadolidium contrast media for imaging of the central nervous system is 1.0 mL/kg aka cc/kg 10 mL/kg 1 mmol/Kg 0.1 mL/mmol
0.1 mL/mmol according to the package insert for contrast media in mri, the standard dosage of gadolinium u 0.2,L/kg (cc per kilogram of body weight) this is equal to 0.1 mmol/kg (0.1 m/mol/kg of gad or 10 c for a 100 lb pt. since there are 2.2 pounds to kilogram, the standard dosage i equal to approx 0.1 cc/lb.
t1 recovery occurs due to nuclei giving up their sorrounding environment' fat has a low inherent energy and can easily absorb energy. water has high inherent energy and cannot easily absorb energy in water the molecular tumbling rate does not match the larmor frequency. in fat molecular tumbling rate matches the larmor frequency. t2 decay occurs as a result of mf of nuclei interacting with each other. fat: molecules spaced closely together tissue with high proton density like brain tissue have a large transverse component of magnezitation and appear bright (high signal) and tissues with low proton density( cortical bone) appear black. as field strenght increases tissues take longer to relax TR controls how far each vector recovers before the slice is excited by the next RF pulse, to achieve t1 the tr must be short enough so that neither fat nor water has sufficient time to fully return b0 TE controls controlls the amount of t2 decay before the signal is received. to achieve t2 the TE must be long enough to give both fat and water time to decay.
1
22 in order to create a thin slice thickness a_____is used Steep slice selection gradient High amplitude slice selection gradient Narrow transmitter bandwith Narrow receive bandwith
1 2 3
38 the approved gad contrast agents are currently indicated for A IV injection for peds B IV injecion for ABD imaging C IV injection for CNS D Intra articular injection for musculoskeletal imaging
1 2 3
155Doubling nsa will increase snr by a factor of 2 4 1.6 1.41
1.41
127 In a spin echo sequence of time between 90 pulse and 180 pulse is TE TR TI 1/2 TE
1/2 te the TE is the time between the 90 pulse and the center of the echo. the 180 pulse occurs halfway between.
119 a sterile tray that has been set up on a table or cart will have a border of ______that must be considered not sterile 1/2" 1" 4" 12"
1/2" the one inch are border or edges of the sterile tray is not considered sterile since those edges are mot likely to come in contact with a non sterile item or person. when pouring solution into a cup on a sterile try, the bottle of solution may leak or drip toward the bottom of the bottle, causing an area of dampness.
32 patients who should be monitored with pulse oximetry during mri procedures include 1 unresponsive and uncommunicative 2 sedated, psychiatric and peds 3 patients who have weak voices or impaired hearing
123
167 the FDA limit the effect of RF absorption to an increase in core body temperature of
1°C
145Reducing the slice thickness by a factor of 2 will reduce the snr ( all other factors remaining constant) by a factor of 2 1.41 2.5 1.5
2
94The mra sequence less sensitive to slow flow is 3-D phase contrast MRA 3-D TOF 2D PC 2D TOF
3D TOF
97 the MRA sequence that can be made sensitive to any flow velocity is the 3-D PCMRA 3DTOF 2DTOF Multislice vascular
3d pc mra TOF MRA use T1 gradient 3D tof: smaller vessels 2D tof larger and slow flow PC MRA sequence use T2 gradient echo Diffussion imaging use EPI, tissues with restricted diffussion appear bright on diffusion imaging.
131 if the slice thickness is reduced by a factor of 2, the factor by which the NSA must be increased to maintain the same snr is 8 1.41 4 2
4 Snr is proportional to slice thickness and square root of the number of signal averages (Square root of 4 is 2
pg 58 whole body averaged: head averaged over: head torso per gram of tissue: extremities per gram of tissue:
4 w/kg for 15 3 w/kg for 10 8 w/kg for 5 12 w/kg for 5
162In July 2003 the FDA center for devices and radiological health modified the limit of RF absorption dose to ___ for the head 2.0 W/kg absorption for 5 mins 3.0 W/kg absorption for 10 mins 4.0 W/kg absorption for 15 mins 12.0 W/kg absorption for 5 mins
4.0 W/kg absorption for 15 mi B
163The food and drug administration limits the allowable RF absorption to .2 W/kg averaged over the body .4 W/kg averaged over the body 2.0 W/kg averaged over the body 4.0 W/kg averaged over the body
4.0 w/kg averaged over the body
98 a normal pulse rate range for an adult is 40 to 60 60 to 90 80 to 100 100 to 130
60 to 90
90Assuming a TR sufficient for full recovery of longitudinal magnetization, maximum signal is produced in the reciever coil when the net magnetization is tipped 180 90 Away from the z axis Through the transverse plane
90 The receiver coils are orientation 90 degrees to the physical z axis
105In a spin echo sequence Flowing blood is normally seen as a signal void because the TE is to long Repetition times used in a spin echo sequence are to long to image flow 90 pulse and 180 pulse are both slice selective Flip angle is always 90 A and C
A and C blood that is excited by the 90 pulse will have moved out of the slice by the time the 180 pulse has been applied. in order to produce a signal, tissues must receive both the 90 and 180 pulses. also low te allows less dephasing
118Susceptibility effects can be reduced by Reducing the fov Reducing tr Reducing te A and c
A and c
121 a decrease in voxel volume leads to a decrease in Chemical shift Aliasing Partial volume averaging A and c
A and c
142 a short T1 inversion recovery stir sequence can suppress signal from Fat Water A gadolidium enjancing lesion A and c
A and c
67What is the most severe form of convulsive seizures A Grand mal B Petit mal C Epilectic D Partial
A grand mal
What imaging a patient with decreased consciousness an area of high signal intensity is noted on both the T1 and T2 weighted images. The type of lesion is likely to be
A hemorrhage(methemoglobin)
65In a 3-D acquisition slices are produced by: A phase encoding gradient applied in the slice selection direction Multiple 180 pulse is how long this late selection direction Sampling multiple lines of K space per sequence repetition Very accurate RF pulses
A phase encoding gradient applied in the slice selection direction
33 pts who have been sedated with diazepam should be monitored w/ A pulse oximetry B ecg gating C peripheral gating D verbal communications
A pulse oximetry
37 what describes an EPI sequence
A train of gradient echoes
107All of the following are examples of behavior that are likely to vary with culture believes except -Direct eye contact is preferred -language spoken may differ -ability to feel pain -giving someone a hug to comfort them
Ability to feel pain
90 blood flow of the area of stenosis (vascular narrowing is known as Laminar flow accelerated flow cortex flow turbulent flow
Accelerated flow
146 the methods for shimming the main magnetic field are Retroactive shimming Active shimming Passive shimming B and c A b and c
Active shimming Passive shimming
38 Rf coil configuration Linear Quadrature Phase array Helmholtz Multichannel
All
126Respiratory artifacts can be reduced by Respiratory gating Respiratory triggering Increasing the number of signals averaged All
All They are for reduction of motion artifact
79 and example of a dipole is A hydrogen nucleus A bar magnet The earth A b and c
All a b and c
150Surface coil cables can potentially cause damage to the patient when They are not frayed and rest along the arm of the patient They are slightly touching the patient and are frayed Looped and not touching the patient
All of them even though the cable may look to be in excellent condition. any cable loop within the imager can potentially receive voltage. therefore, cables that touch the patient are automatically looped, give n that the human body i a conductive and the patient completes the loop.
120 flow artifact can be reduced by gradient momment nulling Spatial presaturation pulses Shortening the te All the above
All the above
102The amount of RF energy necessary to produce a 45 flip angle is determined by the Coil being used Amplitude (power) and duration of the RF pulse Strength of the external magnetic field All the above
All the above The smaller the coil, the less the rf energy required for a given flip angle. The longer the duration of the pulse and the greater its amplitude, the greater the flip angle. Increasing the strength of the external field will increase the amount of power needed for a given flip angle
Part C5 It's typical gradient echo sequence begins with a 90 RF pulse 180 RF pulse Alpha pulse that varies with desired image contrast Alpha pulse below 10
Alpha pulse that varies with desired image GrE sequence begins with a RF pulse with flip angle that varies (depending upon the image contrast desired) Typically , GrE sequence use short TR to keep the scan time short. regarding flip angle on GrE sequence.
118Changing the B value alters the Amplitude, timing and or duration of the diffusion gradient Amplitude of the phase encoding gradient Spatial resolution
Amplitude, timing and or duration of the diffusion gradient
17 The components that make up the circle of Willis include
Anterior cerebral arteries, posterior cerebral arteries, anterior communicating artery, and posterior communicating artery
87Fourier transformation is performed in the Fourier transformation Array processor K spacer RF amplifier
Array processor
248 short axis views of the heart resemble images that are
Axial To the plane of the heart muscle
A permanent magnet usually is constructed of magnetize ceramic bricks or magnetize alloy made of aluminum, ______ and ______ A steel,nickel B Nickel, cobalt C cobalt,tungsten D Tungsten, nickel
B
51 A normal serum creatine range is A: 0.2-1 mg/dL B 0.6-1.5 mg/dL C 0.8-2.5 mg/dL D 1.2-3.0 mg/dL
B 0.6-1.5 mg/dL
62Patients who are at an increased risk of reactions to gadolinium include 1 A history of asthma or allergies 2 Prior contrast reactions 3 hemolytic anomalies 4 all patients
B 1 & 2
49which of the following blood test would not be used to assess the pt risk of hemorrhaging during an invasive procedure such as a biopsy A Prothrombin time PT B Hematocrit C International Normalized Ratio (INR) D Platelet count
B Hematocrit
24 All of the following may be considered an example of battery except A Touching the pt without consent B Sharing pt info with another tech C Imaging the wrong body part D Restraining the pt
B Sharing pt info with another tech
10 Which of the following statements is incorrect regarding the principle of the double effect? A the action must be morally neutral or good B The good effect is not the only intentions C The good effect must be equal to or greater in importance than the bad effect D The bad effect must not be the means by which the good effect is accomplished
B The good effect is not the only intentions
13 Which is the most likely type of law under which a suit is brought against a technologist for performing unintentional acts that fall below the standard of care and result in pt injury? A felonious B Tort C Criminal D administrative
B Tort
104 single order gradients moment Nulling does not compensate for Accelerated flow Reverse flow Constant velocity flow B and c
B and c single order gradient moment nulling only compensate for first order motion, such a flow with constant velocity
102 The following is (are) important in MRA sequences to minimize the loss of signal due to dephasing within a voxel Long TR Small Voxels Short TE B and C
B and c with longer TEs, more time is given for intravoxel dephasing, thereby reduing the signal from within the vessel. with larger voxels, inhomogeneities within the voxel are increased , and these also increase intravoxel dephasing and reduce signal intensity
155Acceptable safe level for exposure to magnetic Fringe fields with respect to patients with cardiac pacemaker's has been reported to be: Between 5G and 15 G Between 5T and 15T Between 15 G and 30 G Below 5g
Below 5g
122the intrinsic contrast mechanism with regard to fMRI is
Bold effect
56A normal range for blood urea nitrogen is A 0.6 - 1.5 mg/100dL B 2.0 - 15.0 mg/100dL C 8.0 - 20.0 mg/100dL D 25.0 - 50 mg/100dL
C 8-20
373Vascular imaging of the venous abdominal vasculature is typically acquired with 2D TOF MRA 3D TOF MRA 2D OC MRA 3D PC MRA CE MRA delayed
CE MRA delayed
357 vascular imaging of the arterial abdominal vasculature Is typically acquired with 2D TOF MRA 3D TOF MRA 2D OC MRA 3D PC MRA CE MRA
CE mra
47 when parallel imaging technique are performed a low ____resolution scan is Acquired prior to the acquisition Test bolus Filtering scale calibration scan Sat pulse
Calibrations scan sense acquisition are performed for rapid imaging with high resolution. SENSE sequence are performed whereby the RF coil are used to encode signal and hence maintain scan time. sense imaging uses a low resolution "calibration scan" to provide info about RF signal detection.
69Which type of shock is caused by failure of the heart to pump enough blood to the vital organs Hypovolemic shock Septic shock Anaphylactic shock Cardiogenic shock
Cardiogenic shock
16The components that make up the basal ganglia include
Caudate nucleus, lentiform nucleus and thalamus
77 Collecting the low frequency (High amplitude signal) Data points in K space at the start of the scan (in a rectilinear fashion) is known as Linear centric elliptic centric reverse centric
Centric
123 all of the techniques below can be utilized to optimally time the start of a contrast enhanced MRA except Automated bolus detection Test bolus Centric k space filling Realtime/fluoro triggering
Centric k space filling
28In an MRI system that uses shim coils B0 homogeneity is adjusted by Changing current in the shim coil Adding metal to different coils within the shim coil Adding current to the gradient coils Turning the shim coil off and on very rapidly
Changing current in the shim coil
120 the basic mr principle with regard to spectroscopy Faradays law of induction Chemical shift Flow related enhancement The bold effect
Chemical shift
73To evaluate the circle of Willis 3DTOFMRA sequences are acquired and displayed as an axial view of all the vasculature. this image is known a Multi Planar reconstruction Segmented image Minimum intensity pixel Collapse image
Collapse image
148The following items are usually allowed to enter the scan room and hide magnetic field system Surgical stainless steel hemostats Surgical stainless steel scissors Copper tools Laryngoscope
Copper tools
34 The best view to evaluate patients with seizures is the Sagittal coronal axial sagittal oblique
Coronal
250The four chamber views of the hearts resemble images that are
Coronal to the plane of the heart muscle
15 to maintain the magnetic field of resistive magnet which of the following should be applied to the magnet coil Water heat current cooling
Current
52 An eGFR of below 15 is indicative of A normal kidney function B A kidney infection C Polycystic kidney D A pt in need of dialysis
D A pt in need of dialysis
64 contrast agent reactions such as Flushing, Hives and nausea are called A psychosomatic B cardiovascular C Anaphylactic D Nonsystemic
D Nonsystemic systemic refers to the entire body being affected. non systemic refers to only a portion of the body being affected. flushing and hives occur only in a particular portion of the body at one time. therefore they are non systemic reponses
48 which blood test for renal function is used in the calculation of eGFR A blood urea nitrogen B Hematocrit C Partial Thromboplastin time D Serum creatinine
D serum creatine
176No biological effects have been reported in humans as a result of exposure to Static magnetic field above 2T time varying magnetic fields RF fields static magnetic fields below 2T
D static magnetic fields below 2T
180 as a conductive medium e.g. blood moves across the magnetic field, and affect known as the magnetic hemodynamic affect occurs, resulting in Increase blood pressure increase temperature elevated T-wave no noticeable effect
Elevated T wave this can be noticed in patients who are monitored with ECG lead and enter the bore of the imager
117 The main purpose of producing/calculating an ADC map is to Reduce the contribution from diffusion effects eliminate the t2 shine thru Increase SNR Reduce T1 weighting
Eliminate T2 shine thru
78 collecting the low frequency (high amplitude signal )data points in k space at the start of the scan in a spiral fashion is known as
Elliptic centric
343Most liver cancers are arterially fed and therefore are visualized on First pass images second past images delayed images All phases
First pass images
84 the technique by which signal data is transformed from a plot of signal intensity overtime to a plot of signal intensity over frequency is known as: Fourier transformation Chemical shift Parts per million volume rendering
Fourier transformation
85The technique by which signal data is modified from the time domain to the frequency domain doing is known as frequency is known as: Fourier transformation Chemical shift Parts per million volume rendering
Fourier transformation
76 following a 90 RF pulse the signal that is created is called Spin echo gradient echo free induction decay FRE
Free induction decay
75 the receiver bW is related to the slope of the: Frequency encoding gradient Phase encoding gradient Slice selecting gradient Transmitting gradient
Frequency
119 Which direction does the zipper artifact occur
Frequency direction
141 center frequency is a factor that determines the Frequency of rf used for excitation Frequency of rf used for signal detection A and b Amplitude and or duration of the rf pulse (to determine flip angle)
Frequency of rf used for excitation Frequency of rf used for signal detection
164To rephase The signal from moving spins gradient moment Nulling techniques use a Rf pulse Gradient Series of short rapid pulses that are strategically timed Flow encoding gradient
Gradient
42When acquiring an fMRI series to map out the visual cortex which of the following pulse sequences would be utilized in order to maximize sensitivity to the bold effect Spin echo EPI gradient echo EPI Fast spin echo with driven equilibrium 3-D spoiled GRE with MTC
Gradient echo epi
8To produce the echo a gradient echo sequence uses a
Gradient magnetic field RF pulse
143 geometric accuracy is determined by the Rf system Shim system Gradient system Main magnet system
Gradient system
46The cerebral cortex is made up of primarily
Gray matter
50 caudate nucleus is made up of primarily
Gray matter
29 the spinal cord is made up of primarily
Gray matter generally speaking , the spinal cord is made up of gray and white matter, whereby the white matter fiber are located along the outer surface of the cord and the gray matter is within. the cord is essentially inside out when compared to the brain. since this i a midline section of the brain and spinal cord, the tissue defined by arrow O is within the cord, and therefore gray matter.
168 The increase in body temperature as a result of RF absorption is
Greatest on the outside becoming less at the center
45 in the equation associated with the larmor equation Y stands for
Gyromagnetic ratio
39 Rf coil configuration that use multiple coils with one single receiver coil included Linear Quadrature Phase array Helmholtz Multichannel
Helmholtz
24In a fast spin echo spatial resolution is associated with the Outer views of K space High amplitude phase encoding gradient Low amplitude phase encoding gradient First phase encoding steps
High amplitude
112 gibbs or truncation, artifact is seen as
High and low signal intensity bands
58On short TR/TE spin echo or fast spin echo imaging sequence, White matter appear
Hyperintense to gray matter
310On T2 weighted MRI images, hemangiomas of the liver appear Hyperintense to normal liver hypointense to normal liver isointense to normal liver only with contrast enhancement
Hyperintense to normal liver
189 gradient magnetic fields are a safety concern because they -Produce large amounts of RF energy -induce currents in conductors -can cause short-term memory loss All
Induce currents in conductors
104when performing an MRA of the cerebral arteries, A saturation ban should be placed Anterior posterior superior inferior
Inferior Superior?
41When imaging the brain of a child under one year the best visualization of gray and white matter differences is demonstrated on a______We're by white matter is hyperintense to Grey matter
Inversion recovery IR imaging rely on T1 relaxation time. The TI allow time for T1 recovery to occur in the gray and white matter, while in the presence of the magnetic field. this phenomenon tend to enhance grey/white matter difference more than conventional spin echo T1 WE image or spoiled gradient echo. for this reason, IR sequence with T1 time of 600ms at 1.5T would be optimal for infant imaging under 1
Using a 3-D acquisition the number of slices allowed when increasing the TR Decrease is not affected increases by a factor of TR/TE Doubles
Is not affected
86For an unconscious patient who has sustained a head injury the main concern is
Keeping a patent airway
132When cleaning clean from
Least contaminated area to most contaminated are
190Reducing the flip angle yields images with More T1 information Less T1 information More T2 information Less T2 information
Less T1 information
123Which type of blood cells responsible for phagocytosis Leukocyte erythrocyte platelets lymphocyte
Leukocyte leukocyte is a white blood cell. phagocytosis occur when microorganism enter the body and fluids carrying white blood cell travel to the site to destroy them
103 the decreased myelination found in brains of children under one year old result in a lack of image contrast. Consequently, in comparison to scamming adults, to achieve T2 weighted images during pediatric brain imaging often requires a Longer TE longer TR longer TI Higher flip angle
Longer TE
131 complete saturation is a condition where
Longitudinal Magnetization is not allowed to recover between excitation
23In fast spin echo sequence the effective TE is the echo that is performed with the Outer views of K space High amplitude phase encoding gradient Low amplitude phase encoding gradient First phase encoding steps
Low amplitude
161Fringe field are less of a concern for Midfield superconductive imagers Lowfield resistive imagers Highfield superconductive images that are shielded Low field, vertical field permanent magnet imagers
Low field, vertical field permanent magnet imagers
50The micro Scopic magnetic field associated with the protons within the magnetic field is known as A:FID B: magnetic moment (u) C: signal echo D: FOV
Magnetic moment
184When a patient is placed within the bore of a magnetic resonance imager, an effect can be noted on the ECG whereby there is an elevator T-wave this effect is known as all except Magnetohydrodynamic affect magnet hydrodynamic affect magnet hemodynamic affect magnetophosphenes
Magnetophosphenes faradays law of induction state that if conductor moves through a magnetic field, a voltage is induced within the conductor. in this case, a the gradient fields are witched on and off during image acquisition, a voltage is induced within the retinal phosphenes. the result is a phenomenon known as magnetophosphenes, where patient experiences the sensation of stars in their eyes.
136factors that effect contrast include all of the following except Tr Te Ti Flip angle Matrix
Matrix
154read 157 in complete spine imaging, to rule out metastatic lesions of the spinal cord, contrast enhancement can be used with T1 we images because Normal cord enhances and metastatic lesions do not. Metastatic lesions(within cord) enhance and normal cord does not Scar enhances and disk does not CSF is bright and cord is dark
Metastatic lesions(within cord) enhance and normal cord does not
188The strength of a gradient magnetic field is measured in
Milli tesla per meter Gauss per centimeter
191 increasing the flip angle yields images with More T1 information Less T1 information More T2 information Less T2 information
More T1 information
41 in which of the following EPI sequences would one expect there to be the least susceptibility distortion artifact Single shot single shot multi shot single shot
Multi shot The multi shot option would result in the shortest train of echoes and thus the least susceptibility artifact
45In an image acquired with a balance GRE sequence all of the following have a high(bright) signal except Blood in the left ventricle CSF IVC normal myocardium
Normal myocardium
309Due to its size and orientation within the body the entire pancreas can possibly be visualize on one imaging section if it is required
Obliquely with thick imaging sections
91Which of the following conditions is common in a patient with COPD Bradycardia Orthopnea dysphagia epistaxes
Orthopnea orthopnea means that a pt has difficulty breathing when lying down. common problem with pt with copd (emphysema)
88 during thermal Equilibrium, the individual Proton precess At same frequency In phase Out of phase Slower
Out of phase The individual spins are precessesing out of phase at equilibrium due to inhomogeneities in the main magnetic field and the effect of other spins
119The MRA Technique that is typically used for the valuation of Venous structures of the head is 2D TOF 3D TOF CE MRA PC MRA
PC MRA
446TMJ imaging is acquired with oblique acquisition. the corona oblique images are acquired with slices
Parallel to the mandibular condyle
107 the superimposition of signal when a large FOV is acquired is known as Wrap around Fold over Aliasing Partial volume averaging
Partial volume averaging
108 the superimposition of signal when a small FOV is acquired is known as all except Wrap around Fold over Aliasing Partial volume averaging
Partial volume averaging
445TMJ imaging is acquired with oblique acquisition. The sagittal oblique images are acquired with slices
Perpendicular to the mandibular condyle
Rf coil configuration that use multiple coils with multiple coils with multiple receivers include Linear Quadrature Phase array Helmholtz Multichannel
Phase array Multichannel
103 the gradient that varies in amplitude with each TR is the Phase encoding gradient Frequency encoding gradient Slice selecting gradient A and b
Phase encoding gradient Frequency encoding gradient amplitude remains the same with each TR
106 passed Multiple coil elements combined with multiple receiver channels is a
Phased array coil
100 a patient recovering from a seizure should be Placed in the recovery position Sims Instructed to lie on their back Administer emergency oxygen Help to move to a more comfortable area
Placed in the recovery position Sims in the recovery position the pt is lying on their left side, semi prone with the upper leg bent for support, so that the mouth is turned downward. this will prevent aspiration of any fluid or vomitus that my be draining from the mouth
116When using an MRA to Evaluate peripheral vascular flow, such as that within the arteries of the legs, saturation pulses are Placed superior to the acquired slices Placed in the acquired slice Placed inferior to the acquired slices Not necessary
Placed inferior to the acquired slices
Pg67 15The components that make up the brainstem include
Pons medulla and midbrain
129 pre-saturation pulses usually occur Prior to the excitation pulse After the 180 pulse Between the 90 and 180 pulse Prior to the Te
Prior to the excitation pulse
172When triggering a scan from the patient ECG, the TR of the sequence is determined by the Number of phase encoding selected Number of phases of the heart cycle being imaged Number frequency encoding selected Pts heart rate
Pts heart rate
41 the sensitivity profile for a given Coil is known as the Pulse profile Spectrum Fid Echo
Pulse profle
42Rf coil configuration That use coils where by the coil is configured with wires or electronic it components that are perpendicular to one another are known as Linear Quadrature Phase array Helmholtz Multichannel
Quadrature
39 for a patient with a suspected pituitary microadenoma, contrast is injected an imaging is performed
Rapidly because lesions have low signal intensity compared to the enhanced pituitary gland
95Frequency can be define by the Rate of phase change per unit time Phase/2 Fourier equation Amplitude of the signal
Rate of phase change per unit time If 360 of phase change occurs in 1 second, then the frequency is one cycle per second 1hz)
128Pre-saturation pulses are often used to Improve spatial resolution Reduce Flow artifacts Reduce scan time Turn Flowing blood right
Reduce flow artifact
119When??? performing a dynamic perfusion exam of the brain utilizing a gadolidium base MR contrast agent, the result of the T2* shortening is Increased mr signal Reduced mr signal Increased acquisition time Increased chemical shift artifact
Reduced mr signal
124In order to re-construct an image using parallel imaging which of the following may be required Test bolus Reference or calibration scan Back projection Half Fourier acquisition
Reference or calibration scan
37 gradient characteristic for speed is known as Amplitude slew rate duty cycle rise time
Rise time
408 the female pelvic imaging the best view for the evaluation of the uterus is Sagittal Axial Coronal Oblique
Sagittal
236The optimal view for evaluation of the aortic arch include Sagittal Axial coronal oblique
Sagittal Oblique
38 To best visualize the pituitary gland in MRI, the optimal planes for high resolution T1 weighted images are Sagittal and coronal Coronal and axial Axial and sagittal Sagittal axial and coronal
Sagittal and coronal
The best view or views for the evaluation of the anterior cruciate ligament
Sagittal and oblique
249 the long axis views of the heart resembles images that are
Sagittal to the plane of the heart muscle
137 In a gradient echo sequence Reducing the flip angle while holding the tr constant reduces T2* contrast we Spin density contrast weighting Saturation Scan time
Saturation
74To evaluate the circle of Willis 3DTOFMRA sequences or acquired and backgrounds issue is carved out to provide better visualization of the intracranial vascular this step is known as Multiplanar reconstruction Segmenting Maximum intensity pixel Collapsed image
Segmenting
25The gradient magnetic field are Always on Superimposed over the main magnetic field Used for contrast control Controlled by rf pulses
Superimposed over the main magnetic field
102The series of nine T2* images are EPI Gradient echo sequence required before (upper left), during and after the administration of contrast (bottom right. The brain tissue on the enhanced image appears darker because godolinium: Shortens the T1 relaxation time Increases the T1 relaxation time Shorince to T2 (and T2*) relaxation Times Increases the T2 (andT2*) relaxation Times
Shorince to T2 (and T2*) relaxation Times
83 evaluation of cardiac function can be provided by any or all of the following except Cardiac Cine Multi phase imaging Perfusion imaging Short axis single slice single phase
Short axis single slice single phase
63To keep scan time at a minimum diffusion imaging Is typically perform with Single shot EPI acquisition Single shot FSE acquisition Multi shot EPI acquisition 2 Multi shot EPI acquisition 4
Single shot EPI acquisition
35 the gradient characteristic that reflects both strength and speed is known as Amplitude slew rate duty cycle rise time
Slew rate
97 slices thickness is controlled by A: length of the gradient field B: slope of the gradient C: receiver bandwidth D a and b
Slope of the gradient
163Gradient moment nulling is most effective when correcting for motion induced signal loss from Pulsating flow No flow Slow constant flow Magnetic field in homogeneities
Slow constant flow
125 When using parallel imaging to reduce acquisition times which of the following is always true Scan time is reduced and spatial resolution is increased Spatial resolution is reduced the greater acceleration factor seletected Snr is not effected unless the acceleration factor is greator than 2 Snr is reduced and spatial resolution is unaffected
Snr is reduced and spatial resolution is unaffected
96Gradient magnetic field are used to Improve snr Spatial encode data Transmit the RF pulse Control the image contrast
Spatially encode the data
105For patients with hearing loss, each of the following would be helpful for effective communication except Avoid noisy backgrounds Speak loudly in a high pitch face the patient as you speak to him Rephrase what you said if necessary
Speak loudly in a high pitch most hearing loss i in the higher pitch or range. for this reason, speaking in a low pitch and speaking very slowly will help the patient who is hearing impaired to understand your directions.
81 Hydrogen nuclei have a magnetic moment because they possess a property called Inversion Flux Spin Resonance
Spin
27A gradient echo sequence in which any residual Transverse Magnetization is removed prior to the next excitation pulse is known as
Spoiled/incoherent Gradient echo sequence were developed a fast scan or rapid changing imaging technique. typically, GrE sequence use short TR to keep scan time low. GrE sequences begin with a RF pulse with flip angle that varies (depending upon the desired image contrast.) regarding flip angle on GrE sequences, flip angle "goes with" TR that goes with T1 relaxation. for thi reason, a low flip angle(5-30) i applied for less T1 info" yielding T2* image. larger flip angle (up to 90) i pplied for "more T1 info" , yielding fast scns with T1 contrast.
28 when a gradient echo sequence is required for dynamic contrast enhanced imaging of the liver _____is performed
Spoiling steady state effect produces T2* characteritic on GrE image. in this case, fast can can only be produced with T2 or T2* image contrast whereby fluid is bright. this technique is known as steady state, or T2* or coherent gradient echo imaging. to reduce steady state (T2*) effect, a technique know a spoiling can be performed to allow for fast scans with T1 contrast. spoiling can be performed by RF spoiling or gradient spoiling. RF spoiling occurs whereby additional RF pule are randomized to spoil away the steady state effect. this technique is known as spoiled gradient echo or incoherent gradient echo imaging. it is performed for rapid T1 imaging for dynamic enhanced imaging of the organs( liver, kidneys etc) and/ or dynamic enhanced MRA sequences
43in the equation associated with the larmor equation Bo stands for
Static magnetic field
11 If the TR of a gradient echo pulse sequence it's considerably less than the T2 (and T2*) The condition that will exist is known as Steady state spin dephasing spin rephrasing spin cancellation
Steady state in a Steady state condition, there will be residual transverse magnetization at the time of the next excitation
77 T2* is a result of dephasing due to a tissues T2 time and T1 Susceptibility, inhomogeneity& chemical shift Molecular weight A and b
Susceptibility, inhomogeneity& chemical shift
86Fourier transformation convert signal data from the FID into the spectrum T or F?
T
32Gradients speed (risetime) and strength (amplitude) is measured in units of mT/M G/cm T/m/s Us %
T/m/s
43 in which of the following sequences would MS plaques appear hyperintense relative to both CSF and normal white matter T2 flair T1 flair T2FSE T2 FSE with RF fat supp
T2 flair
78 The peak signal strength of a spin Echo is less than the initial signal strength of the free induction decay because of T1 T2* Spin density T2 relaxation
T2 relaxation
150Any conventional spin echo sequence it is possible to create multiple images each with different amounts of T1 weighting Phase encoding T2 weighting Spatial resolution
T2 weigting
66T2 + T2'=
T2* T2' Is associated with susceptibility, inhomogeneity, and chemical shift.To remove the steady state spoiling can be perform this yields rapid T1 imaging for dynamic enhanced imaging or enhanced mra sequences
65 gradients echo steady state sequences acquired with a short TR and flip angle combinations along with a moderately long TE yield images with T1 contrast T2 contrast PD contrast T2* contrast
T2* contrast
55 scan time for EPI pulse sequences can be calculated by
TR X #shots x NSA
68 with conventional spin echo each line of k spaces filled in each Frequency encoding period. TE period TR period Excitation period
TR period
141 another name for T1 Alpha Theta Sigma Tau
Tau
160 MR imagers are magnetic field shielded such that Any metallic object and enter the scan room The Fringe field is confined to /within the bore The French field is confined to within/the scan room There is no Fringe field
The French field is confined to within/the scan room
105K space is: the image in its natural state A negative of an mr image The raw data from which a an mr image is created What comes after j space
The raw data from which a an mr image is created
200There is no signal arising from within the lung because There are no protons in air There is no air in the lung during image acquisition There are not enough mobile protons in Air Air and moving blood have the same number of protons and therefore both appear black
There are not enough mobile protons in Air
87 The condition reached with the few seconds of hydrogen being placed in a magnetic field is described as Resonance FID Phase coherence Thermal equilibrium
Thermal equilibrium
47A condition where by there are more spins in line with the magnetic field then opposed is known as
Thermal equilibrium There are more spins in the low energy sake
108 which of the following is not a true statement regarding patient with altered state of consciousness
They will not remember conversations or statements made while it altered state
140in an inversion recovery pulse sequence, The time between the initiation 180 pulse the 90 pulse is known as Te Tr Ti T1
Ti
121Having acquired a 3d TOF when producing an mra projection image set using the mip technique, which of theFollowing can appear bright and therefore the same as flow within a vessel Tissues with long t2 relaxation time Tissues or substance with extremely short T1 relaxation times Polycystic astrocytoma Any substance with an extreme short T2 relaxation time
Tissues or substance with extremely short T1 relaxation times
130 gradient echo sequences use flip angles Less than 90 That vary between pulse repetition Control saturation affects To reduce SAR for larger patients
To control saturation effects with gradient echo pulse sequences, increasing the flip angle will increase the saturation effects seen in the image and thus increase the T1 WE
33The patient with a history of seizures can be image using cardiac gating To minimize pulsatile flow motion artifact in the temporal lobe To monitor the patient for potential seizures To avoid talking to the patient throughout the study To make vessels appear black
To minimize pulsatile flow motion artifact in the temporal lobe
139in an inversion recovery pulse sequence, Image contrast is controlled by Tr and te Ti Ti and te Tr te and ti
Tr te and ti
29Shimming an MRI was performed by all the following except Changing current in the shim coil Adding metal to different coils within the shim coil Adding current to the gradient coils Turning the shim coil off and on very rapidly
Turning the shim coil off and on very rapidly
18 in a superconducting magnet the magnetic field strength is increased by increasing the Amount of cryogens Temperature Internal pressure Turns of wire
Turns of wire
185The FDA limited time varying magnetic field is
Until the patient experience peripheral nerve stimulation
31Gradients speed (rise time) Is measured in units of mT/M G/cm T/m/s Us %
Us
Main purpose of cine kinematics: Visualize motion and function Visualize blood flow Measure muscle strenght Impress referring physician
Visualize motion and function
44 in the equation associated with the larmor equation Wo stands for
Voltage
91the swirling blood flow that occurs just passed the area of stenosis is known as Laminar flow accelerated flow vortex flow turbulent flow
Vortex flow
44 in a balance GRE acquisition the contrast weighting is T1 T2 T2* Weighted for the ratio of T2/T1
Weighted for the ratio of T2/T1
52 internal capsule is made up of primarily
White matter
113Cardiac cine acquisitions typically utilize
a gradient echo pulse sequence
344 hemangiomas are benign lesions(typically watching weight lesions) that are Venus fed.And therefore visualized on First pass images second past images delayed images All phases
delayed images since most liver cancers are arterially fed, they are bet visualized on the first pas. in contrast, other lesion (hemangiomas) are demonstrated with delayed enhancement
42 The proper way of treating contrast media extravasation is to
remove needle, hold pressure on the vein until bleeding stops, then apply ice
55 which of the layers of a blood vessel is made of fibrous, connective tissue A tunica adventitia B tunica media C Tunica intima D capillaries
tunica adventitia the outer layer of the artery or vein can be called either the tunica adventitia or tunica externa
pg 59 in 2003 the FDA/CDRH limit for TVMF is"
until pt feels painful nerve stimulation gradient speed or rise time i expreed in microseconds (us) combination of rise time and strength is expressed as the slew rate and expressed in units of tesla per seconds