Mock 5

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What term describes the signal that follows the application of the initial 900 RF pulse Select one: a. spin echo b. gradient echo c. FID d. Hahn echo

FID

The inversion recovery pulse sequence that is used to suppress CSF in proton density and T2 weighted images is known as _________ . Select one: a. FLAIR b. STIR c. SSFP d. FISP

FLAIR

Due to the decreased efficiency in refocusing spins, this pulse sequence is extremely sensitive to magnetic field homogeneity: Select one: a. SE b. GRE c. IR d. Three Dimensional Fourier Transform (3DFT) SE

GRE

Which of these pulse sequences is the most "flow" sensitive"? Select one: a. SE b. GRE c. IR d. Short T1 Inversion Recovery (STIR)

GRE

Parallel imaging techniques are also known as all of the following except: Select one: a. SENSE b. SMASH c. GRAPPA d. SAT

SAT

When parallel imaging techniques are preformed, a low resolution ______ scan is acquired prior to the acquisition: Select one: a. test bolus b. filtering scan c. calibration scan d. sat pulse

calibration scan

Gradient echo pulse sequences that preserve left over transverse magnetization are said to be _______ . Select one: a. incoherent b. coherent c. consistent d. inconsistent

coherent

To produce a echo, a gradient echo pulse sequence uses: Select one: a. gradient magnetic field only b. RF pulse only c. combination of a and b d. switching device e. combination of any two RF pulses

combination of a and b

To produce the echo, a gradient echo pulse sequence uses a: Select one: a. gradient magnetic field only b. RF pulse only c. combination of a and b d. switching device e. a combination of any two RF pulses

combination of a and b

In a gradient echo pulse sequence, which parameter directly affects image weighting? Select one: a. nex b. field of view c. flip angle d. matrix

flip angle

What function does the initial 1800 RF pulse have in an IR sequence/ Select one: a. dephases the net magnetization vector b. flips the net magnetization into the negative longitudinal plane for greater T1 relaxation range c. is followed by the collection of the echo d. suppresses the signal from fat

flips the net magnetization into the negative longitudinal plane for greater T1 relaxation range

STIR sequences can suppress the signal from all of the following except Select one: a. fat within bone marrow b. gadolinium-enhancing lesions c. retro-orbital fat d. fluid (CSF)

fluid (CSF)

A gradient echo sequence in which any residual transverse magnetization is removed prior to the next excitation pulse is known as: Select one: a. non-phasic b. incoherent c. non-residual d. magnetization prepared

incoherent

Gradient echo pulse sequences that eliminates left over transverse magnetization are said to be ________ . Select one: a. incoherent b. coherent c. consistent d. inconsistent

incoherent

Dynamic enhanced MRA sequences of the renal arteries are performed with the use of: Select one: a. incoherent gradient echoes b. coherent gradient echoes c. steady-state gradient echoes d. T2* gradient echoes

incoherent gradient echoes

Gradient echo sequences acquired for high signal from fluid are known as all of the following except: Select one: a. coherent gradient echoes b. incoherent gradient echoes c. steady-state gradient echoes d. T2* gradient echoes

incoherent gradient echoes

A gradient echo sequence in which any residual transverse magnetization is removed prior to the next excitation pulse is known as: Select one: a. nonphasic b. incoherent/spoiled c. nonresidual d. magnetization prepared

incoherent/spoiled

What is the image quality result on SE images if the TE is lengthened? Select one: a. increases the contrast based on the T2 of the tissues b. reduces the contrast based on the T2 of the tissues c. reduces the contrast based on the T1 of the tissues d. increases the contrast based on the T1 of the tissues

increases the contrast based on the T2 of the tissues

Using flip angles of 100 or less in a GRE pulse sequence will result in what effect on the image? Select one: a. less T2*-weighting b. less SNR c. longer relaxation times d. more T1-weighting

less SNR

What parameters are used to create spin echo (SE) T2-weighted images? Select one: a. short TE and short TR b. short TE and long TR c. long TE and long TR d. long TE and short TR

long TE and long TR

Which of the following statements is false, regarding a gradient echo sequence? Select one: a. long TE improves the T1 contrast b. RF flip angles which are less than 900 allow for greater signal-to-noise ratios when using short TRs c. a shallow flip angle allows for greater residual longitudinal magnetization d. gradient echoes are not rephased by an RF pulse

long TE improves the T1 contrast

In a fast spin echo (FSE) sequence, acquired with long effective TE (T2-weighted images), scan time can be reduced by the selection of: Select one: a. shorter ETL b. longer ETL c. there is no ETL change that affects scan time d. larger FOV

longer ETL

The contrast of an image acquired with a T2-prepared fast gradient echo sequence is most similar to an image acquired with which of the following types of sequences? Select one: a. inversion recovery b. fast spin echo c. spoiled gradient echo d. steady state gradient echo

fast spin echo

The spin echo pulse sequence that performs more than one phase encoding step per TR is known as ________. Select one: a. conventional spin echo b. fast spin echo c. RARE d. b and c

fast spin echo

The gradient that is on during the production of the echo is the: Select one: a. phase b. slice selection c. frequency d. oblique

frequency

In a gradient echo pulse sequence, which gradient is used to dephase and rephase nuclei? Select one: a. slice select gradient b. phase encoding gradient c. frequency encoding gradient d. none of the above

frequency encoding gradient

A 1800 RF pulse followed by a 900 pulse, followed by another 1800 RF pulse is what type of pulse sequence? Select one: a. inversion recovery b. fast spin echo c. spin echo d. spoiled gradient echo

inversion recovery

The type of spin echo pulse sequence that begins with a 1800 inversion RF pulse and is followed by a 900 excitation pulse is known as ___________ . Select one: a. echo planar b. gradient echo c. inversion recovery d. gradient reversal

inversion recovery

During an inversion recovery pulse sequence, the time between the 1800 inversion pulse and the 900 excitation pulse is known as ___________. Select one: a. echo time b. repetition time c. inversion time d. reversion time

inversion time

If the phase resolution of 256 is desired, then the TR must be repeated (for 1 NSA): Select one: a. 192 times b. 256 times c. 512 times d. twice

256 times

The number of shots is calculated by: Select one: a. TR x #PEs b. #PE's / ETL c. ETL / #PEs d. #PE's x NSA

#PE's / ETL

A single shot FSE sequence is acquired when: Select one: a. #PE's = 256 and ETL = 256 b. #PE's = 128 and ETL = 256 c. #PE's = 256 and ETL = 128 d. #PE's = 256 and ETL = 64

#PE's = 256 and ETL = 256

A multi-shot FSE sequence is acquired (with 4 shots) when: Select one: a. #PE's = 256 and ETL = 256 b. #PE's = 128 and ETL = 256 c. #PE's = 256 and ETL = 128 d. #PE's = 256 and ETL = 64

#PE's = 256 and ETL = 64

Which of the following field strengths would require the shortest (lowest) T1 time to suppress/null the signal from fat when acquiring a STIR sequence in an MR scan of the knee? Select one: a. 0.35 T b. 1.0 T c. 1.5 T d. 3.0 T

0.35 T

If the TR is reduced, how is the image quality affected?1. SNR decrease2. T2 contrast increases3. spin density weighting is increased Select one: a. 1 b. 3 c. 1 and 2 d. 1 and 3

1

In conventional spin echo pulse sequences, how many lines of K-space are filled per TR? Select one: a. 1 b. 2 c. 4 d. 6

1

In conventional spin echo pulse sequences, how many phase encoding steps are achieved per TR? Select one: a. 1 b. 128 c. 192 d. 256

1

Which of the following may be seen in a fast gradient echo image? 1. T1 contrast 2. T2 contrast 3. magnetic susceptibility Select one: a. 1 b. 2 c. 1, 2 d. 1, 2, and 3

1 AND 2

Which of these statements are true regarding rephased GRE pulse sequences? 1. rephased GRE sequences preserve transverse signal 2. both longitudinal and transverse signals contribute to the next RF pulse 3. rephased GRE sequences increase T1 dependence Select one: a. 1 b. 2 c. 1 and 2 d. 1 and 3

1 AND 2

Which of these statements is true regarding spoiled GRE sequences?1. spoils the transverse signal2. increases T2* dependence3. only longitudinal signals contribute to the next RF pulse Select one: a. 1 b. 3 c. 1 and 2 d. 1, and 3

1 AND 3

Regarding flow, which of these causes a decrease in signal intensity? 1. high-flow void 2. turbulence 3. diastolic pseudo-gating Select one: a. 1 b. 1 and 2 c. 2 d. 1, 2, and 3

1 and 2

Coherent, incoherent, and steady state free precession (SSFP) pulse sequences can be differentiated according to whether or not they use FID or spin echo signals. Which of the following are correct? 1. coherent pulse sequences use a gradient reversal to rephase both the FID and the dephasing portion of the spin echo 2. Incoherent pulse sequences use a gradient reversal to rephase both FID and rephasing portion of the spin echo 3. SSFP uses an RF pulse to initiate the rephasing process and a rewinder to move the spin echo to occur before the RF pulse Select one: a. 2 b. 3 c. 2 and 3 d. 1 and 3

1 n 3

In a fast spin echo sequence with an echo train of 12, how many RF pulses are applied for a given slice, during one TR period? Select one: a. 1 b. 6 c. 12 d. 13

13

_____________ is not a characteristic of the steady state gradient echo pulse sequence. Select one: a. user-selectable RF flip angle b. refocused transverse magnetization following the formation of the echo c. 180 DEGREE RF pulse d. spin-spin interactions

180 DEGREE RF pulse

What mechanism rephases the dephasing hydrogen nuclei in a SE sequence? Select one: a. 180 RF pulse b. 90RF pulse c. free induction decay signal (FID) d. gradient reversal after the 900 RF pulse

180degree RF pluse

An inversion recovery (IR) spin echo sequence begins with a: Select one: a. 90d RF pulse b. 180d RF pulse c. 45d RF pulse d. a or b

180degree RF pulse

An inversion recovery spin echo sequence begins with a: Select one: a. 90d RF pulse b. 180d RF pulse c. 45d RF pulse d. a or b

180degree RF pulse

Gradient recalled echo (GRE) pulse sequences are accomplished using the following events: Select one: a. 900 RF, 1800 RF, 1800 RF b. 1800 RF pulse, gradient reversal c. 900 RF pulse, gradient reversal d. less than 900 RF pulse, gradient reversal

180degree RF pulse, gradient reversal

A typical inversion recovery (IR) spin echo uses which the pulse sequence? Select one: a. 90d, 180d,180d b. 180d, 90d, 180d c. 50 RF pulse d. none of the above

180degree, 90degree, 180degree

In a T2-prepared fast gradient echo sequence which uses a 900, 1800, 900 preparation scheme, how many 900 RF pulses are applied for a single image with 192 phase steps in its matrix? Select one: a. 384 b. 256 c. 192 d. 2

2

In an SE, what is the term for the time between the 900 RF pulse and the 1800 RF pulse? 1. TE 2. tau 3. TE/2 Select one: a. 1 b. 2 c. 2 and 3 d. 1, 2, and 3

2 and 3

If a phase resolution of 256 is desired, then the TR must be repeated (for 1 NSA): Select one: a. 192 times b. 256 times c. 512 times d. twice

256 times

If a given conventional spine echo pulse sequence takes 12 minutes to acquire, a fast spin echo sequence using an ETL of 6, with all other factors that affect scan time remaining the same, will take: Select one: a. 2 minutes b. 1 minute c. 6 minutes d. 4 minutes

2min

If a given conventional spin echo pulse sequence takes 12 minutes to acquire, a fast spin echo sequence using an ETL of six, with all other factors that affect scan time remaining the same, will take: Select one: a. 2 minutes b. 1 minute c. 6 minutes d. 4 minutes

2minutes

Which of the following may be seen in a steady state gradient echo image? 1. T1 contrast 2. T2 contrast 3. magnetic susceptibility Select one: a. 1 b. 2 c. 3 d. 1, 2, and 3

3

Which of the following statements is true regarding a fast spin echo sequence with an echo train of 16 compared to a fast spin echo sequence with an echo train of 4, assuming both use the same TR and all echoes are separated by 10 ms, with the 1st echo at TE = 30 ms? 1. the sequence with an echo train of 4 should have a scan time of about 74% less than the one with an echo train of 16 2. the sequence with an echo train of 16 will have better resolution than the sequence with an echo train of 4 3. the sequence with an echo train of 16 will be lower in signal-to-noise ratio than the one with an echo train of 4 Select one: a. 1 b. 2 c. 3 d. 2, and 3

3

Which of the following statements is true? 1. HB experiences less electron shielding than HA 2. HA experiences a lower magnetic field than HB 3. HA has a greater frequency than HB Select one: a. 1,2,and 3 b. 1 c. 2 d. 3

3

Place the following SE pulse sequence events in the correct order. 1. signal measurement 2. 1800 RF pulse 3. 900 RF pulse Select one: a. 1, 2, 3 b. 2, 1, 3 c. 3, 2, 1 d. 1, 3, 2

3,2,1

Which of the following flip angles would result in the largest longitudinal component, assuming the net magnetization is initially in the longitudinal direction? Select one: a. 30 b. 45 c. 60 d. 75

30

When nulling the signal from a specific tissue using an inversion recovery sequence, selecting an inversion time that is _____ of the T1 relaxation time of that tissue is proper. Select one: a. 43% b. 69% c. 80% d. 37%

37%

In a fast spin echo pulse sequence, if the echo train length is increased by a factor of four, the scan will be: Select one: a. 1 times as fast b. twice as fast c. 3 times as fast d. 4 times as fast

4 times as fast

Consider a dual contrast spin echo pulse sequence in which the 900 RF pulse is applied at time = 0, the center of the 1st echo forms at time = 15 ms, and the center of the end echo forms at time = 90 ms. The 1800 RF pulse to form the echo used for the T2-weighted image must have been applied at ____ ms. Select one: a. 37.5 b. 45.0 c. 52.5 d. 55.0

52.5

In a fast spin echo pulse sequence with an echo train of 8, if the 1st 4 echoes contribute to a proton density image, and the last four echoes contribute to a T2-weighted images, how many repetitions are required to the fill the raw data of a 256 x 256 T2-weighted image Select one: a. 256 b. 64 c. 32 d. 16

64

Consider a spin echo pulse sequence in which the 900 RF pulse is applied at time = 0 and the maximum signal of a spin echo forms at time = 15 ms. The 1800 pulse must have been applied at _____ ms. Select one: a. 5.0 b. 5.5 c. 7.0 d. 7.5

7.5

In a conventional spin echo pulse sequence with a TE of 20 ms and an echo duration of 5 ms, the receiver must turn on _____ ms after the center of the 1800 pulse. Select one: a. 5 b. 7.5 c. 10 d. 12.5

7.5

Which of the following RF flip angles would result in the largest transverse component, assuming the net magnetization is initially in the longitudinal direction? Select one: a. 30 b. 45 c. 60 d. 75

75

Which of the following best describes a SE sequence? Select one: a. 90 pulse followed by a 180 pulse b. 180 pulse followed by a 90/180 combination c. train of gradient pulses d. train of spin echo

90 pulse followed by a 180 pulse

A spin echo pulse sequence is characterized by which of the following? Select one: a. 180degree excitation pulse followed by a 90degree rephasing pulse b. 90degree excitation pulse followed by a 180degree rephasing pulse c. 90degree excitation pulse followed by a 90degree rephasing pulse d. none of the above

90degree excitation pulse followed by a 180degree rephasing pulse

A typical spin echo (SE) sequence uses which pulse sequence? Select one: a. 90d, 90d b. 90degree, 180degree c. 180d, 180d d. 180d, 90d

90degree, 180degree

Which of the following is a disadvantage of a fast spin echo pulse sequence? Select one: a. increased effects of flow motion b. bright fat on T2 weighted images c. increased resolution d. a and b

A AND B

Which of the following is a method of eliminating residual transverse magnetization? Select one: a. Digital RF spoiling b. gradient rewinding c. gradient spoiling d. a and c

A AND C

What will be the effect of shortening the TE time? 1. increases signal-to-noise ratio (SNR) 2. increases the spin density contrast weighting 3. reduces contrast based on T2 relaxation times Select one: a. 1 b. 3 c. 2 and 3 d. 1, 2, and 3

ALL

Which of the following is a disadvantage of a gradient echo pulse sequence? Select one: a. decreased signal to noise ratio b. increased sensitivity to magnetic susceptibility artifacts c. increased gradient noise d. all of the above

ALL

Which of the following is an advantage of a fast spin echo pulse sequence? Select one: a. reduced scan times b. improved quality c. increased T2 weighting d. all of the above

ALL

Which of the following is an advantage of gradient echo pulse sequences? Select one: a. decreased scan time b. increased sensitivity to flow c. volume acquistions possible d. all of the above

ALL

Which of the following may be T1-weighted? 1. spin echo image 2. inversion recovery image 3. gradient echo image Select one: a. 1 and 2 b. 2 and 3 c. 1 and 3 d. 1, 2, and 3

ALL

Which of these statements is not true regarding steady state? Select one: a. TR must be shorter than the T1 and T2 of the tissues b. TR must equal the tau of the spin angle c. during the acquisition, the flip angle and the TR maintain the steady state d. all of the above are true statements

ALL

A FLAIR sequence is used to suppress the signal from: Select one: a. MS plaques b. gadolinium c. fat d. CSF

CSF

What is the term for an echo formed by the application of two successive 900 RF pulses? Select one: a. partial saturation echo b. Hahn echo c. spin echo d. gradient recalled echo

Hahn echo

When doing an MRV of the superior sagittal sinus, a saturation band should be placed _______ to the axial slices. Select one: a. anterior b. posterior c. superior d. inferior

INFERIOR

Which of the following pulse sequences allow tissues to relax over twice the dynamic range possible with SE pulse sequence? Select one: a. 450 GRE b. 3DFT c. EPI d. IR

IR

The inversion recovery pulse sequence that is used to suppress fat in a T1 weighted image is know as _________ . Select one: a. FLAIR b. STIR c. SSFP d. FLASH

STIR

When doing an MRA of the IVC, a saturation band should be placed ________ to the axial slices. Select one: a. anterior b. posterior c. superior d. inferior

SUPERIOR

When doing an MRA of the carotid arteries, a saturation band should be placed ______ to the axial slices> Select one: a. anterior b. posterior c. inferior d. superior

SUPERIOR

When doing an MRA of the circle of Willis, a saturation band should be placed ______ to the axial slices. Select one: a. anterior b. posterior c. superior d. inferior

SUPERIOR

In an echo planar pulse sequence, pre-inverting tissue with a 1800 RF pulse before excitation produces what type of image weighting? Select one: a. T1 weighting b. T2 weighting c. proton density weighting d. none of the above

T1 weighting

In which of the following sequences would MS plaques appear hyperintense relative to both CFS and normal white matter? Select one: a. T2 FLAIR b. T1 FLAIR c. T2 FSE d. T2 FSE with RF fat suppression

T2 FLAIR

The peak signal strength of a spin echo is less than the initial strength of the FID because of _________. Select one: a. magnetic susceptibility b. T1 relaxation time c. T2 relaxation d. proton concentration

T2 relaxation

In an echo planar pulse sequence, using a long TE produces what type of weighting? Select one: a. T1 weighting b. T2 weighting c. proton density weighting d. none of the above

T2 weighting

Gradient echo pulse sequences that have coherent residual transverse magnetization produce what type of image weighting? Select one: a. T1 weighting b. T2* weighting c. proton density weighting d. a and c

T2* weighting

In a fast spin echo pulse sequence, the time from the 900 pulse to the echo is called; Select one: a. TE b. TM c. TR d. TI

TE

In an IR pulse sequence, what is the term for the time between the initial 1800 and the 900pulse? Select one: a. TE b. TR c. TI d. T1

TI

What is the time from an inverting pulse to a 900 pulse called? Select one: a. TR b. TE c. TI d. T1

TI

What is the time interval between the 900 RF pulse and a subsequent 900 RF pulse applied to the same slice? Select one: a. TD b. TI c. TE d. TR

TR

What is the correct formula for determining the total scan time in minutes, for a 3DFT image? Select one: a. TR (sec) x TE x Number of excitations (NEX) x Number of phase encoding steps (Npe) b. TR (sec) x TE x Npe x NEX x Number of slices (Nslices)/60,000 (msec) c. TR (sec) x Npe x NEX/60 (sec) d. TR (sec) x Npe x NEX x Nslices/60 (sec)

TR (sec) x Npe x NEX x Nslices/60 (sec)

Scan time for 2D IR pulse sequence can be calculated by which formula? Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x # slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA

Scan time formula for 2D SE pulse is: Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x #slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA

Scan time formula for EPI pulse sequence is: Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x # slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA

Scan time for 2D GRE pulse sequences can be calculated by using which formula? Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x # slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA x # slices

Scan time for a "volume" acquisition can be calculated by: Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x # slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA x # slices

Scan time for a 2D FSE pulse sequence can be calculated by: Select one: a. TR x #PEs x NSA b. TR x #PEs x NSA x # slices c. TR x #PEs x NSA/ETL d. TR x #shots x NSA

TR x #PEs x NSA/ETL

In a volume acquisition, the scan time is: Select one: a. TR x NSA x BW x thickness b. TR x NSA x phase encodings x slab thickness c. TR x NSA x # of phase encodings x ETL d. TR x NSA x # of phase encodings x # of slices

TR x NSA x # of phase encodings x # of slices

Which RF pulse series produces several true T2-weighted SE images with each TR? Select one: a. a 90 RF pulse, a series of 180 RF pulses and the collection of echoes b. a series of 90 RF pulses followed by the collection of an echo c. series of 180 RF pulses followed by the collection of echoes d. a 23 RF pulse followed by the collection of echoes

a 90 DEGREE RF pulse, a series of 180 DEGREE RF pulses and the collection of echoes

The type of pulse that uses only 900 RF pulses is known as __________. Select one: a. partial saturation pulse sequence b. gradient echo pulse sequence c. saturation recovery pulse sequence d. a and b

a and b

Gradient echo pulse sequences that have incoherent residual transverse magnetization are primarily used to create what type of image weighting? Select one: a. T1 weighting b. T2 weighting c. proton density weighting d. a and c

a and c

The number of 1800 rephasing pulses performed in a fast spine echo pulse sequence is known as its _________ . Select one: a. inversion factor b. turbo factor c. echo train length d. a and c

a and c

Which of the following statements is false? Select one: a. a gradient echo is the same as an FID b. gradient echo sequences generally have shorter TRs than spin echo sequences c. gradient echo sequences are not the best choice for identifying metastatic lesions d. gradient echoes are not rephased by an RF pulse

a gradient echo is the same as an FID

What do spin density images measure: Select one: a. magnetic susceptibility b. a subset of all protons in fat and water molecules c. specific absorption rate d. magnetic field strength

a subset of all protons in fat and water molecules

Changing the TR will directly affect which of the following? Select one: a. slice thickness b. orientation of the image plane c. acquisition time d. field of view

acquisition time

Gradient echo sequences can yield either a T1 or T2* characteristics, with influences caused by all of the following except: Select one: a. susceptibility b. inhomogeneity c. chemical shift d. aliasing

aliasing

The 1800 pulse that follows the initial 900 pulse in a spin echo sequence will cause NMR signal to reappear while correcting for: Select one: a. slight magnetic field inhomogeneities b. chemical shift c. slight magnetic susceptibility effects d. all of the above

all

The 1800 pulse that follows the initial 900 pulse in a spin echo sequence will cause the NMR signal to reappear while correcting for: Select one: a. slight magnetic field inhomogeneities b. chemical shift c. slight magnetic susceptibility effects d. all of the above

all

The gradient echo pulse sequence that produces true T2 image weighting is known as: Select one: a. PSIF b. SSFP c. T2 FFE d. all of the above

all

A typical gradient echo sequence begins with a: Select one: a. 90degree RF pulse b. 180degree RF pulse c. alpha pulse that varies with desired image contrast d. alpha pulse below 100

alpha pulse that varies with desired image contrast

In an ideal tissue which experiences no spin-spin interactions which of the following statements is true? Select one: a. amplitude of the magnetization originally placed into the transverse plane is greater than the amplitude of the gradient echo b. amplitude of the gradient echo is greater than the amplitude of the magnetization originally placed into the transverse plane c. amplitude of the magnetization originally placed into the transverse plane is equal to the amplitude of the gradient echo d. amplitude of the gradient echo is greater than the amplitude of the spin echo

amplitude of the magnetization originally placed into the transverse plane is equal to the amplitude of the gradient echo

If the T1 of an inversion recovery pulse sequence is chosen such that the magnetization of silicone, from a silicone breast implant, is relaxing through zero when the 900 RF pulse is transmitted, what type of signal can be expected from the silicone in the resulting image. Select one: a. bright b. dark c. speckled d. not enough information is given

dark

In a gradient echo pulse sequence, the use of an RF pulse to eliminate residual transverse magnetization is known as ________ . Select one: a. digital RF spoiling b. frequency spoiling c. gradient spoiling d. none of the above

digital RF spoiling

The pulse sequence that performs a series of 1800 rephasing pulses and echoes is known as ________ . Select one: a. echo planar b. inversion train c. echo plane d. none of the above

echo planar

The type of pulse sequence that fills all lines of K-space per TR is known as: Select one: a. fast spin echo b. steady state free precession c. echo planar d. spin echo

echo planar

Which of the following types of pulse sequences would be the best choice for a cardiac perfusion study? Select one: a. inversion recovery b. conventional spin echo c. fast spin echo d. echo planar

echo planar

In a RARE pulse sequence, the multiple number of echo times that create image weighting are averaged together to produce what is known as the _________ . Select one: a. effective TR b. effective T1 c. effective TE d. none of the above

effective TE

Because __________, the inversion recovery method of fat suppression should not be used with MR contrast agents? Select one: a. patient may experience a burning sensation b. pathology and the surrounding tissue will enhance c. presence of the contrast agent will alter the T2-weighting of the images d. enhanced tissues as well as the fat may be suppressed

enhanced tissues as well as the fat may be suppressed

Short tau inversion recovery (STIR) sequences are typically used for the evaluation of all of the following except: Select one: a. musculoskeletal contusions b. fat suppression c. lesions within the retro-orbital fat d. fluid (CSF)

fluid (CSF)

In a gradient echo pulse sequence, a system malfunction causes the 1st pulse of the readout gradient to remain on one millisecond too long. The gradient echo will: Select one: a. form earlier than the selected TE b. form later than the selected TE c. not form d. form at the correct time

form later than the selected TE

The "readout" gradient is also known as the: Select one: a. phase b. slice selection c. frequency d. oblique

frequecy

The gradient that is on during the production of the echo is called the: Select one: a. phase encoding gradient b. slice select gradient c. frequency encoding gradient/readout gradient d. flow encoding gradient

frequency encoding gradient/readout gradient

In which of the following pulse sequence would you expect to find the shortest TR? Select one: a. spin echo b. gradient echo c. inversion recovery d. fast spin echo

gradient echo

In which of the following pulse sequences would you expect to find the shortest TR? Select one: a. spin echo b. gradient echo c. inversion recovery d. fast spin echo

gradient echo

The type of pulse sequence that uses a gradient instead of 1800 RF pulse to rephase dephasing nuclei is known as _________ . Select one: a. spin echo b. inversion echo c. fast spin echo d. gradient echo

gradient echo

When 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? Select one: a. spine echo EPI b. gradient echo EPI c. fast pin echo with driven equilibrium d. 3D spoiled GRE with MTC

gradient echo EPI

In a gradient echo pulse sequence, the use of a gradient to eliminate residual transverse magnetization is known as ________ . Select one: a. digital RF spoiling b. frequency spoiling c. gradient spoiling d. none of the above

gradient spoling

In a fast spin echo sequence, spatial resolution is associated with the: Select one: a. central lines of K-space b. high amplitude phase-encoding gradients c. low amplitude phase-encoding gradients d. 1st phase-encoding steps

high amplitude phase-encoding gradients

Which of the following is an advantage of using spin echo pulse sequence? Select one: a. high signal to noise ratio b. decreased resolution c. long scan times d. none of the above

high signal to noise ratio

In a fast spin echo sequence, the effective TE is the echo that is performed with: Select one: a. outer view of K space b. high amplitude phase encoding gradients c. low amplitude phase encoding gradients d. 1st phase encoding steps

low amplitude phase encoding gradients

In a fast spin echo sequence, the effective TE is the echo that is performed with the: Select one: a. outer views of K-space b. high amplitude phase-encoding gradients c. low amplitude phase-encoding gradients d. 1st phase-encoding steps

low amplitude phase-encoding gradients

During a conventional 10 minute T2 spin echo scan with 1 signal average, most of the contrast information is collected for the image during: Select one: a. minutes 1 and 2 b. minutes 5 and 6 c. minutes 9 and 10 d. the entire scan

minutes 5 and 6

In which of the e following EPI sequences would one expect to be the least susceptibility (distortion) artifacts? Select one: a. single-shot SE-EPI, 256 phase x 256 frequency b. single-shot GRE-EPI, 512 phase x 192 frequency c. multi-shot (4-shot) SE-EPI, 256 phase x 256 frequency d. single-shot SE-EPI, 192 phase x 192 frequency

multi-shot (4-shot) SE-EPI, 256 phase x 256 frequency

In an image acquired with a balanced GRE sequence, all of the following have high (bright) signal except: Select one: a. IVC b. CSF c. blood in the left ventricle d. normal myocardium

normal myocardium

What type of pulse sequence begins with a 900 RF pulse and is immediately followed by the collection of the echo? Select one: a. spin echo b. inversion recovery c. short TI inversion recovery d. partial saturation

partial saturation

T2-weighted fluid attenuated inversion recovery (FLAIR) sequences are typically used for the evaluation of: Select one: a. musculoskeletal contusions b. fat c. retro-orbital fat d. peri-ventricular white matter disease

peri-ventricular white matter disease

As the TE of a gradient echo sequence is varied, _______ cause fat and water to have signal intensities which cycle from similar to different. Select one: a. phase effects of chemical shift b. spin-spin interactions c. magnetic susceptibility differences between tissues d. magnetic inhomogeneities

phase effects of chemical shift

Which of the following may not be seen in a conventional spin echo image? Select one: a. T1 contrast b. T2 contrast c. phase effects of magnetic susceptibility d. proton density contrast

phase effects of magnetic susceptibility

What are the additional RF pulses called that are used to saturate out hydrogen nuclei prior to excitation? Select one: a. oversaturation b. presaturation c. flow compensation d. magnetic moment

presaturation

Phase encoding is performed: Select one: a. after frequency encoding b. prior to frequency encoding c. in place of frequency encoding d. during frequency encoding

prior to frequency encoding

A long TR msec (3000 msec or greater) and a short TE (shorter than 40 msec) would acquire an image that would produce which type of image contrast? Select one: a. T1-weighted b. T2-weighted c. T2*-weighted d. proton density-weighted (PD-weighted)

proton density-weighted (PD-weighted)

In a CSE pulse sequence, a 900 RF pulse is followed by a 1800 RF pulse. How much more power does it take to deliver a 1800 RF pulse compared with the 900 RF pulse? Select one: a. twice b. half c. quadruple d. eight times

quadruple

Which of the following is not related to the receiver bandwidth? Select one: a. readout gradient amplitude b. range of frequencies transmitted to select the slice thickness c. range of frequencies encoded in the echo d. chemical shift artifact

range of frequencies transmitted to select the slice thickness

What is a way to reduce the scan time without directly affecting image contrast? Select one: a. reduce TR b. reduce Npe c. use a gradient reversal d. reduce the TE

reduce Npe

In a gradient echo pulse sequence, transverse magnetization that is leftover from a previous excitation pulse is known as _________ . Select one: a. residual transverse magnetization b. magnetization transfer c. chemical misregistration d. none of the above

residual transverse magnetization

In a gradient echo pulse sequence, the process of reversing the slope of the phase encoding gradient after readout to preserve residual transverse magnetization is known as ________ . Select one: a. warping b. spoiling c. rewinding d. none of the above

rewinding

In a GRE sequence, if the flip angle is lowered while holding the TR constant, which of the following would be reduced? Select one: a. chemical shift artifact b. magnetic susceptibility c. saturation d. scan times

saturation

In a fast spin echo (FSE) sequence, acquired with short effective TE (T1-or-PD-weighted images), blurring can be reduced by the selection of: Select one: a. shorter ETL b. longer ETL c. there is no ETL change that affects blurring d. larger FOV

shorter ETL

To keep scan time at a minimum, diffusion imaging is typically performed with: Select one: a. single-shot EPI acquisition b. single-shot FSE acquisition c. Multi-shot (two-shot) EPI acquisition d. Multi-shot (4-shot) EPI acquisition

single-shot EPI acquisition

Which of the following is the pulse sequence that is used most commonly? Select one: a. inversion recovery b. gradient echo c. spin echo d. echo planar

spin echo

Which of the following is not included in T2* contrast? Select one: a. magnetic susceptibility differences b. spin-spin interaction c. magnetic inhomogeneities d. spin-lattice relaxation

spin-lattice relaxation

Which of the following in not rephased by the 1800 RF pulse in a spin echo pulse sequence? Select one: a. phase effects of chemical shift b. spin-spin interactions c. magnetic susceptibility differences between tissues d. magnetic inhomogeneities

spin-spin interactions

The _______ pulse sequences use the least amount of RF energy. Select one: a. dual contrast spin echo b. fat suppressed inversion recovery c. fast spin echo with an echo train of 4 d. spoiled gradient echo

spoiled gradient echo

In a gradient echo pulse sequence, the process of eliminating residual transverse magnetization is known as ________ . Select one: a. warping b. spoiling c. rewinding d. none of the above

spoiling

When a gradient echo sequence is acquired for dynamic contrast-enhanced imaging of the liver, __________ is performed. Select one: a. additional 1800 pulse b. initial 1800 pulse c. spoiling d. coherence

spoiling

If the TR of a gradient echo pulse sequence is considerably less than the T2 (and T2*), the condition that will exist is known as: Select one: a. steady state b. spin dephasing c. spin rephasing d. spin cancellation

steady state

The condition that occurs in a gradient echo pulse sequence when the TR is shorter than the T1 and T2 relaxation times of tissue is known as __________ . Select one: a. chemical shift b. steady state c. frequency shift d. phase shift

steady state

The gradient echo pulse sequence that is characterized by an echo time that is longer than its repetition time is known as: Select one: a. echo planar b. steady state free precession c. spin echo d. fast spin echo

steady state free precession

Which of the following is not a characteristic of the spoiled gradient echo pulse sequence? Select one: a. user-selectable RF flip angle b. echo formed by gradient refocusing c. steady state transverse magnetization following the formation of the echo d. elimination of residual transverse magnetization before the next TR period

steady state transverse magnetization following the formation of the echo

Gradient echo sequences acquired for the evaluation of hemorrhagic lesions rely on: Select one: a. susceptibility b. inhomogeneity c. chemical shift d. aliasing

susceptibility

What is the term for the time from the excitation pulse to the refocusing pulse and from the refocusing pulse to the echo? Select one: a. time delay b. dead time c. tau time

tau time

If a single echo was corrupted, due to a static discharge from the patient's wool socks, during the 1st 30 sec. of a 5 minute spin echo knee study, how would you expect the resultant image to appear? Select one: a. image would appear normal b. overall contrast of the image would be degraded c. there would be a stripe artifact in the top 10% of the image d. there would be a stripe artifact throughout the image

there would be a stripe artifact throughout the image

Which of the following best describes an EPI Select one: a. 900 pulse followed by a 1800 pulse b. 1800 pulse followed by a 900/1800 combination c. train of gradient echoes d. train of spin echoes

train of gradient echoes

Which of the following best describes an FSE? Select one: a. 900 pulse followed by a 1800 pulse b. 1800 pulse followed by a 900/1800 combination c. train of gradient echoes d. train of spin echoes

train of spin echoes

Gradient echo sequences can yield either T1 or T2* characteristics: Select one: a. true b. false

true

In an echo planar pulse sequence, proton density weighting can be produced by which of the following techniques? Select one: a. applying a 1800 RF pulse to pre-invert tissue before excitation b. using a short TE c. using a long TE d. using a 1800 rephasing pulse

using a short TE

What is the term for the distance traveled between the positive and negative lobe of the velocity-encoding gradient? Select one: a. velocity b. turbulence c. gradient moment nulling d. laminar flow

velocity

In a balanced GRE acquisition, the contrast weighting is: Select one: a. T1 weighted b. T2 weighted c. T2* weighted d. weighted for the ratio of T2/T1

weighted for the ratio of T2/T1

To acquire a set of T1-weighted images, the spoiled gradient echo sequence ______ work and the steady state gradient echo sequence _______ work. Select one: a. would, would not b. would not, would c. would, would d. would not, would not

would, would not


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