Final 200 Exam Practice Questions

Question 1

Question #1 : All of the following artifacts except ________ occur along the phase encoding axis.

Answer 1

Chemical shift

Question 2

Question #2 : Magnetic susceptibility artifacts are more prominent with _____________ sequences.

Answer 2

Gradient echo

Gradient echo sequences are more susceptible to metallic artifacts due to the lack of 180º refocussing RF pulse which would reduce field inhomogeneities.

Question 3

Question #3 : A remedy for a Gibbs truncation artifact would be:

Answer 3

Increase the number of phase encodings

To correct for Gibbs truncation artifact, increase the number of phase encodings or reduce the FOV (while maintaining matrix)

Question 4

Question #4 : The largest ventricle in the heart is the _______ and is identified by Letter ____ in Image 66.

Answer 4

Left ventricle; D

Question 5

Question #5 : Calculate the effective TR for a patient with a heart rate of 70 beats / min.

Answer 5

857 ms

If the heart rate is 70 beats per minute, the R-R interval (effective TR) would be calculated as such: 60,000 milliseconds (60 seconds per minute, and there are 1000 milliseconds per second) ÷ 70 (heart rate) which = 857 milliseconds TR.

Question 6

Question #9 : The HEIGHT of a peak on an MR spectrum correlates to the _________ of a substance that was detected.

Answer 6

Amount

Question 7

Question #10 : Contrast in Diffusion Weighted Imaging (DWI) depends on:
I. The degree to which molecular mobility is impaired (water restriction)
II. The sensitivity of the sequence to Brownian motion
III. T1 relaxation time
IV. The direction of water diffusion
V. T2 relaxation time

Answer 7

I, II and IV

Contrast in Diffusion Weighted Imaging (DWI) depends on the degree to which molecular mobility is impaired (water restriction), the sensitivity of the sequence to Brownian motion, and the direction of water diffusion.

Question 8

Question #11 : The final result in a perfusion study is:

Answer 8

A set of calculated images which indicate various flow characteristics

The final result in a perfusion study is a set of calculated images which indicate various flow characteristics.

Question 9

Question #12 : The final result in a spectroscopy study is:

Answer 9

A spectrum of specific detected metabolites

Spectroscopy (MRS) allows doctors to obtain biochemical information about the chemical components in tissues (metabolites) of the human body in a non-invasive way.

Question 10

Question #13 : The imaging technique that employs a very rapid pulse sequence while the patient is at rest or performing a task is:

Answer 10

Functional MRI

The imaging technique that employs a very rapid pulse sequence while the patient is at rest or performing a task is known as Functional MRI.

Question 11

Question #16 : If the TR in a gradient echo sequence is less than the T2 (or T2*), the resulting condition is known as:

Answer 11

Steady state

The condition of steady state occurs when the TR in a gradient echo is less than the T2 (or T2*), resulting in residual transverse magnetization at the time of the next excitation pulse

Question 12

Question #17 : A gradient echo sequence in which all the remaining residual transverse magnetization is removed prior to the next excitation pulse is known as:

Answer 12

Incoherent or spoiled

A spoiled gradient echo sequence removes any residual transverse magnetization prior to the next excitation pulse.

Question 13

Question #18 : In a Fast Spin Echo (FSE) sequence, acquired with a long TE, yielding T2 weighted images, scan time can be reduced by:

Answer 13

Using longer ETL

Longer ETL (echo train lengths) shorten overall scan times in Fast Spin Echo (FSE) sequences.

Question 14

Question #19 : In a Fast Spin Echo (FSE) sequence, acquired with a short echo time (TE), yielding T1 or PD weighted images, blurring can be reduced by:

Answer 14

Using shorter ETL

In a Fast Spin Echo sequence, increasing the # ETL (echo train lengths) can lead to an increase in blurring.

Question 15

Question #20 : The structures that comprise the rotator cuff in the shoulder are:
I. Deltoid muscle
II. Subscapularis muscle and tendon
III. Infraspinatus muscle and tendon
IV. Teres minor muscle and tendon
V. Supraspinatus muscle and tendon
VI. Trapezius muscle and tendon

Answer 15

II, III, IV and V

The rotator cuff is comprised of the subscapularis muscle and tendon, infraspinatus muscle and tendon,teres minor muscle and tendon and the supraspinatus muscle and tendon

Question 16

Question #21 : T2 weighted FLAIR (fluid attenuated inversion recovery) sequences are typically used for evaluation of:

Answer 16

White matter disease

T2 weighted FLAIR (fluid attenuated inversion recovery) sequences are typically used for evaluation of periventricular white matter.

Question 17

Question #22 : Short TAU inversion recovery (STIR) sequences are typically used for the evaluation of all the following EXCEPT:

Answer 17

Fluid (CSF)

Short TAU inversion recovery (STIR) sequences are typically used for the evaluation of compression fracture, lesions within retro-orbital fat, musculoskeletal contusions and fat suppression.

Question 18

Question #23 : If the pulse sequence shown in Image 77 were a fast spin echo sequence, the number of lines of k-space filled for each TR period would be:

Answer 18

2

In a fast spin echo sequence, multiple echoes are used to fill multiple lines of k-space for each TR period, thus reducing scan time by the number of echoes. Image 77’s example would shorten the overall scan time by a factor of 2, for each 180° echo.

Question 19

Question #24 : When a gradient echo sequence is selected for fast, breath hold dynamic contrast-enhanced imaging of the abdomen, _____________ is utilized.

Answer 19

Spoiling

To reduce the steady state (T2*) effect, a technique known as “spoiling” can be employed to allow for fast scans with T1 contrast. RF spoiling occurs when additional RF pulses are used to “spoil away” the steady state effect (residual transverse magnetization) before the next excitation, yielding T1 contrast for dynamic imaging of organs or CE MRA sequences.

Question 20

Question #25 : Gradient echo sequences requiring high signal from fluid are known as all of the following EXCEPT:

Answer 20

Incoherent gradient echo

Gradient echo sequences requiring high signal from fluid are known as T2* gradient echo, Steady-state gradient echo or coherent gradient echo. Incoherent gradient echo (or spoiled gradient echo) sequences yield T1 contrast due to the removal of residual transverse magnetization before the next excitation.

Question 21

Question #26 : Dynamic enhanced MRA sequences of the mesenteric arteries are performed using:

Answer 21

Incoherent gradient echo

Gradient echo sequences requiring high signal from fluid are known as T2* gradient echo, Steady-state gradient echo or coherent gradient echo. Incoherent gradient echo (or spoiled gradient echo) sequences yield T1 contrast due to the removal of residual transverse magnetization before the next excitation. This fast T1 contrast can be utilized in dynamic MRI imaging of the abdominal organs or CE MRA techniques.

Question 22

Question #27 : Gradient echo sequences can yield either T1 or T2* characteristics, with influences caused by all of the following EXCEPT:

Answer 22

Inversion time

Gradient echo sequences can yield either T1 or T2* characteristics, with influences caused by susceptibility, Chemical shift, and inhomogeneities.

Question 23

Question #28 : Which of the following field strengths would require the shortest TI time to suppress the signal from fat when performing a STIR sequence in an MRI of the ankle?

Answer 23

0.5T

Question 24

Question #29 : If the desire is to null the signal from a specific tissue using an inversion recovery sequence, the inversion time (TI) selected should be ______ of the T1 relaxation time of that tissue.

Answer 24

69%

If the desire is to null the signal from a specific tissue using an inversion recovery sequence, the inversion time (TI) selected should be 69% of the T1 relaxation time of that tissue.

Question 25

Question #30 : When parallel imaging techniques are utilized, a low resolution __________ is acquired prior to the acquisition.

Answer 25

Calibration scan When parallel imaging techniques are utilized, a low resolution calibration scan (reference tissue scan) is acquired prior to the acquisition.

Question 26

Question #31 : In a Fast Spin Echo sequence, the number of shots is calculated by:

Answer 26

#Phase encodings / ETL In a Fast Spin Echo sequence, the number of shots is calculated by #Phase encodings / ETL.

Question 27

Question #32 : In a medical malpractice lawsuit, the ______ must be able to prove medical malpractice.

Answer 27

Patient plaintiff

Question 28

Question #33 : Healthcare workers generally practice ___________, which states the "goal is to do no harm."

Answer 28

Beneficence Healthcare workers generally practice beneficence, which states the "goal is to do no harm."

Question 29

Question #34 : Referencing the White Paper on MRI safety, individuals identified as "Level 2" personnel include:

Answer 29

Those with extensive MRI safety training, including the magnetic, gradient and RF fields Those with extensive MRI safety training, including the magnetic, gradient and RF fields of an MR system are identified as "Level 2" personnel

Question 30

Question #35 : Referencing the White Paper on MRI safety, individuals identified as "Level 1" personnel include:

Answer 30

Those with limited MRI safety training Those with limited MRI safety training are identified as "Level 1" personnel

Question 31

Question #36 : Which of the following is NOT a type of fomite found in an MRI environment?

Answer 31

Injection syringe A fomite is an object that carries microorganisms from one person to another via indirect contact.

Question 32

Question #37 : Diseases, such as malaria, in which microorganisms are transferred via an insect, come under the classification of __________ infections.

Answer 32

Vector borne Diseases, such as malaria, in which microorganisms are transferred via an insect, come under the classification of Vector borne infections

Question 33

Question #38 : Which type of blood cell is responsible for phagocytosis?

Answer 33

Leukocyte A leukocyte is a white blood cell. Phagocytosis occurs when microorganisms enter the body and fluids carrying white blood cells travel to the site to destroy them.

Question 34

Question #39 : The source of infection where pathogens thrive in numbers sufficient to cause a threat is known as a:

Answer 34

Reservoir The source of infection where pathogens thrive in numbers sufficient to cause a threat is known as a reservoir.

Question 35

Question #40 : Droplet contamination frequently occurs via:

Answer 35

Coughing Droplets can be spread by sneezing, coughing and speaking, and depositing the droplets into the mucous membranes of the face. Droplets travel short distances of 3 feet or less and do not remain suspended in air.

Question 36

Question #41 : Referencing the Centers for Disease Control and Prevention (CDC), what type of isolation precautions should be used for HIV-positive patients in the MRI suite?

Answer 36

Standard (universal) Adhere to STANDARD precautions for ALL patients at ALL times for safety and infection control best practices.

Question 37

Question #42 : During movement or transfer of patients, a urinary collection bag should be placed:

Answer 37

Below the level of the urinary bladder During movement or transfer of patients, a urinary collection bag should be placed below the level of the urinary bladder. Urinary tract infections acquired nosocomially are often due to the incorrect placement of the urinary collection bag.

Question 38

Question #43 : Another term used for "fever" is:

Answer 38

Febrile The term febrile is defined as pertaining to or marked by fever; feverish. For example, a febrile seizure or convulsion is a seizure caused by a high fever.

Question 39

Question #44 : A technologist may be permitted to administer oxygen in an emergency situation. The most common rate used is:

Answer 39

2L/min Oxygen is considered a medication and in order to be administered, must be prescribed by a physician. A technologist may administer oxygen in an emergency situation. The most frequent rate used is 2L/min.

Question 40

Question #45 : 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

Answer 40

I and II only Longer TE's provide more T2 contrast, but reduced signal-to-noise ratios

Question 41

Question #46 : 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

Answer 41

II only As the TE is increased, the available number of slices are decreased (longer TE means fewer slices can fit into the TR period)

Question 42

Question #47 : Which of the following sequences is the most insensitive to magnetic field inhomogeneity?

Answer 42

Spin echo Spin echo sequences contain 180° RF refocusing pulse(s), which aid in correcting for local field inhomogeneities, therefore making them the most INSENSITIVE to chemical shift, susceptibility or inhomogeneity.

Question 43

Question #48 : As the TR is increased, I. SNR is increased II. Available number of slices is increased III. T2 information is maximized

Answer 43

I and II only As the TR is increased, SNR is increased and the available number of slices is increased.

Question 44

Question #49 : CSF suppression is performed with which type of technique?

Answer 44

FLAIR FLAIR (Fluid Attenuated Inversion Recovery) is a technique that nulls the signal from CSF in order to achieve better white matter visualization

Question 45

Question #58 : What element in the body is the principal nucleus utilized in clinical MR imaging?

Answer 45

Hydrogen

Question 46

Question #59 : The extent to which a material or tissue becomes magnetized in an external magnetic field is called:

Answer 46

Magnetic susceptibility

Question 47

Question #60 : The energy used to form MRI images is ____________ the patient's tissues.

Answer 47

Emitted from Unlike other imaging modalities, MRI obtains signal information via the energy emitted from the patient's tissues following RF excitation pulses.

Question 48

Question #61 : The _________ is defined as the resonant frequency, and is equal to the product of the magnetic field and the gyromagnetic ratio.

Answer 48

Precessional frequency The precessional frequency is defined as the resonant frequency, and is equal to the product of the magnetic field and the gyromagnetic ratio.

Question 49

Question #62 : 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

Answer 49

I, II and IV Force on an object in an magnetic environment depends on the mass and the ferromagnetic properties of the object, as well as the strength of the magnetic field.

Question 50

Question #63 : A magnetic vector possesses attributes of both __________ and _____________.

Answer 50

Magnitude; direction

Question 51

Question #64 : Immediately following the application of the 90° RF pulse, the precessing protons:

Answer 51

A and C only - begin to precess in phase; tip into the transverse plane. Immediately following the application of the 90° RF pulse, the precessing protons begin to precess in phase and tip into the transverse plane.

Question 52

Question #69 : Image 43 is an example of an MR angiography of the abdominal aorta and runoff of the lower extremities. This was acquired with dynamic contrast enhancement and:

Answer 52

Stepping table motion from the abdomen down to the feet following the contrast injection

Question 53

Question #70 : When imaging the female pelvis, the most optimal view for evaluation of the ovaries is the:

Answer 53

Coronal

Question 54

Question #71 : When imaging the female pelvis, the most optimal view for evaluation of the uterus is the:

Answer 54

Sagittal

Question 55

Question #87 : The ___________ valve lies between the left atrium (LA) and the left ventricle (LV).

Answer 55

Mitral

Question 56

Question #91 : Which of the following parameter adjustments help to improve SNR in an MR image? I. Increase TR II.Reduce Phase Matrix III. Reduce Pixel Size IV. Increase FOV V. Reduce rBW VI. Increase rBW VII. Increase NSA VIII. Decrease NSA IX. Increase ETL X. Decrease ETL

Answer 56

I, II, IV, V, VII and X Increasing TR, Reducing the Phase Matrix, Increasing the FOV, Reducing (narrowing) the receive Bandwidth, Increasing NEX/NSA and Reducing the #ETL all help to improve SNR in an MR image.

Question 57

Question #92 : Which of the following parameter adjustments reduce the overall SNR in an MR image? I. Decrease TR II.Reduce Phase Matrix III. Reduce Pixel Size IV. Decrease FOV V. Reduce rBW VI. Increase rBW VII. Increase NEX VIII. Decrease NEX IX. Increase ETL X. Decrease ETL

Answer 57

I, III, IV, VI, VIII and IX A Decrease in TR, Reduction in Pixel Size, Decrease in FOV, Increase (widening) of the receiver Bandwidth, Decrease in NEX and an Increase in #ETL all negatively impact SNR in an MR image.

Question 58

Question #93 : Fat has a _______ T1 relaxation time and a ________ T2 relaxation time.

Answer 58

Short; short Fat has a short T1 relaxation time and a short T2 relaxation time

Question 59

Question #94 : Water has a __________ T1 relaxation time and a ________ T2 relaxation time.

Answer 59

Long; long Water has a long T1 relaxation time and a long T2 relaxation time.

Question 60

Question #95 : Which of the following is NOT affected by changing the slice thickness?

Answer 60

The T2 contrast Echo Time (TE) is the controlling factor of T2 weighting/contrast in an image; slice thickness does nothing to alter the T2 information.

Question 61

Question #96 : Which parameter combination will yield the best spatial resolution?

Answer 61

3mm slice thickness, 256 x 256 matrix Thinner slices yield improved spatial resolution(detail), in addition to smaller pixel size (higher phase matrix)

Question 62

Question #97 : In a fast spin echo sequence with a 25 cm FOV, 224 x 320 matrix, TR 2500, 100 TE, 3mm slice thickness, 12 ETL and 4 NEX, the scan time would be:

Answer 62

3 minutes 7 seconds Scan time formula: TR x Phase Matrix x NEX ÷ ETL = total in milliseconds, then ÷ 1000 to achieve scan time in seconds. In this example, TR2500 x 224ph encodings x 4NEX / 12ETL /1000. Be careful if you divide by 60 to achieve the scan time in decimal format (This example computes to 186.6 seconds, if you divide by 60 you get 3.11 seconds, which is 3 minutes 7 seconds, not 3 minutes 11 seconds)

Question 63

Question #98 : Reducing the FOV (field of view) only will result in:

Answer 63

Decreased signal-to-noise A reduction in FOV will yield a decrease in SNR, but an increase in spatial resolution.

Question 64

Question #99 : The smallest object that can be resolved in an image acquired with a 24cm FOV and a 272 x 272 matrix is _________ mm.

Answer 64

0.88mm Convert the cm of the FOV into mm by multiplying 24 x 10. 240 / 272 = 0.88mm

Question 65

Question #100 : What would the scan time be in a 3D volume acquisition as follows: TR 24 ms, TE 7 ms, Flip Angle 15°, FOV 20cm, 2mm slice thickness, 76 slices, 176 x 256 matrix, 1 NEX?

Answer 65

5min 21sec 3D scan time formula: TR x Phase Matrix x NEX x # slices

Question 66

Question #101 : Choose the correct slice thickness to create an isotropic voxel for the following: TR 2000, TE 90, Matrix 272 x 272, FOV 24cm.

Answer 66

0.88mm An isotropic voxel has equal measurements in all three dimensions (phase, frequency and slice direction) FOV/Matrix = 0.88mm

Question 67

Question #102 : The pixel size of the images which result from a 3D acquisition using a 260mm FOV, a 320 x 320 matrix, 32 slices and a volume of 64 mm is:

Answer 67

0.81 x 0.81 mm FOV ÷ Matrix = pixel size..... 260 ÷ 320 = 0.81mm

Question 68

Question #103 : All of the following would aid in reducing scan time EXCEPT:

Answer 68

Reduction in ETL Reducing the # ETL increases overall scan time

Question 69

Question #104 : All of the following yield a higher signal-to-noise ratio EXCEPT:

Answer 69

Increase in TE An increase in TE will yield a decrease in SNR

Question 70

Question #105 : 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:

Answer 70

A and/or C only 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 Half Fourier, or Zero Fill.

Question 71

Question #106 : Reducing the number of lines filled in k-space will produce an image:

Answer 71

A, D and E only Reducing the number of lines filled in k-space reduces the number of phase encoding steps, resulting in shorter scan time, an increase in overall SNR, but a decrease in spatial resolution.

Question 72

Question #107 : RF energy used in MRI is classified as:

Answer 72

Low energy, nonionizing radiation RF energy used in MRI is classified as low energy, nonionizing radiation.

Question 73

Question #108 : If the flip angle is doubled, RF deposition increases by a factor of:

Answer 73

4 If the flip angle is doubled, RF deposition increases by a factor of 4.

Question 74

Question #109 : Calculate the voxel volume for the following pulse sequence: TR 2000, TE 85, FOV 24cm, Matrix 272 x 320, 3mm slice thickness, 3 NSA.

Answer 74

1.98mm3 To calculate voxel volume, first determine pixel area. FOV/matrix x FOV/matrix = pixel area. Pixel area x slice thickness = voxel volume. 240/272 x 240/320 = 0.66 mm2 (pixel area). 0.66 x 3 = 1.98mm3

Question 75

Question #110 : Calculate the pixel area for the following sequence: TR 4000, TE 120, FOV 36cm, 408 x 512 matrix, 2 NEX, ETL 12.

Answer 75

0.62 mm2 FOV/matrix x FOV/matrix = pixel area. 360/408 x 360/512 = 0.62 mm2.

Question 76

Question #111 : _______ is when only half the views of k-space are filled in the frequency axis.

Answer 76

Partial or fractional echo Partial or fractional echo is when only half the views of k-space are filled in the frequency axis, an acceleration technique used to shorten TR and TE.

Question 77

Question #112 : As the number of phase encodings is increased from 256 to 512, SNR (signal to noise ratio):

Answer 77

Decreases As the number of phase encodings is increased from 256 to 512, SNR (signal to noise ratio) decreases (less protons per voxel)

Question 78

Question #113 : The readout gradient is usually turned on during the sampling or readout of the peak echo and also during which other process?

Answer 78

Frequency encoding The readout gradient is usually turned on during the sampling or readout of the peak echo and also during frequency encoding.

Question 79

Question #114 : A narrow receiver bandwidth:

Answer 79

Increases susceptibility artifact A narrow receiver bandwidth increases susceptibility artifact, and should never be used in the presence of metal implants.

Question 80

Question #115 : What effect would using a steep slice select slope and/or narrow bandwidth have on slice thickness?

Answer 80

Slices will be thin Steep slice select gradient slope yields thin slice thickness

Question 81

Question #116 : Creating additional images in various planes from a 3D data set is accomplished by a technique known as:

Answer 81

Multi-Planar reconstruction (MPR) The MPR function enables the user to create additional images from an acquired 3D data set.

Question 82

Question #117 : The process that digitizes the MR signals is known as:

Answer 82

Fourier transform The process that digitizes the MR signals is known as Fourier transform.

Question 83

Question #118 : To increase the voxel volume, which parameters would be adjusted?

Answer 83

FOV, slice thickness and matrix FOV, slice thickness and matrix are the parameters used to make adjustments to voxel volume.

Question 84

Question #119 : The Ernst angle can be defined as the optimal ___________ that yields the ____________ signal for a particular spin in the least amount of time.

Answer 84

Flip angle; maximum The Ernst angle can be defined as the optimal flip angle that yields the maximum signal for a particular spin in the least amount of time.

Question 85

Question #120 : Which of the following parameter adjustments will SHORTEN scan time in an MR pulse sequence? I. Decrease TR II. Increase TR III. Increase ETL IV. Decrease ETL V. Decrease NEX VI. Increase NEX VII. Enable Half-fourier VIII. Increase parallel imaging factor IX. Decrease parallel imaging factor X. Enable anti-aliasing

Answer 85

I, III, V, VII and VIII Decreasing TR, increasing the #ETL, Decreasing NEX, enabling half-scan and Increasing parallel imaging factor all have an impact on shortening overall scan times in an MR pulse sequence.

Question 86

Question #121 : Which of the following parameter adjustments will LENGTHEN scan time in an MR pulse sequence? I. Decrease TR II. Increase TR III. Increase ETL IV. Decrease ETL V. Decrease NEX VI. Increase NEX VII. Enable Half-fourier VIII. Increase parallel imaging factor IX. Decrease parallel imaging factor X. Enable anti-aliasing

Answer 86

II, IV, VI and IX Increasing TR, Decreasing the # ETL, Increasing NEX and Decreasing the parallel imaging factor all play a role in lengthening scan time in an MR pulse sequence.

Question 87

Question #122 : The _____________ imaging plane would be the most optimal slice orientation for evaluation of Arnold Chiari Malformation and its inferior cerebellar tonsillar herniation.

Answer 87

Sagittal Arnold–Chiari malformation, or often simply Chiari malformation,consists of a downward displacement of the cerebellar tonsils through the foramen magnum and is best visualized with the Sagittal plane.

Question 88

Question #123 : When imaging a hemorrhagic infarct in the brain, which pulse sequence would demonstrate the magnetic susceptibility effects better?

Answer 88

Gradient echo Due to the lack of 180° RF refocusing pulse, the gradient echo sequence is more susceptible to magnetic field inhomogeneities, such as hemosiderin from blood products. The hemosiderin is highly magnetic because it is principally iron.

Question 89

Question #124 : _______ sequences are performed to suppress CSF (cerebro-spinal fluid)and aid in the detection of demyelination.

Answer 89

FLAIR FLAIR (FLuid Attenuated Inversion Recovery) sequences suppress the signal from CSF to detect small white matter lesions, tumors, and evaluation of stroke.

Question 90

Question #125 : The medial and lateral rectus muscles are located in the:

Answer 90

Eyes The medial rectus muscle is a muscle in the orbit. As with most of the muscles of the orbit, it is innervated by the inferior division of the oculomotor nerve (CN III)

Question 91

Question #126 : In the TMJ’s, the articular disc lies between what two anatomical structures?

Answer 91

Mandibular fossa and mandibular condyle In the TMJ’s, the articular disc lies between the mandibular condyle and the mandibular fossa.

Question 92

Question #127 : If the third ventricle is dilated, but the fourth ventricle is not, there would then be pathology associated with:

Answer 92

Aqueduct of Sylvius The cerebral aqueduct, or Aqueduct of Sylvius, is a CSF containing structure that connects the third ventricle to the fourth ventricle.

Question 93

Question #128 : Which fissure divides the frontal and parietal lobes from the temporal lobes?

Answer 93

Sylvian fissure The Sylvian fissure divides the frontal and parietal lobes from the temporal lobes.

Question 94

Question #129 : The __________________ runs the length of the falx cerebri.

Answer 94

Superior sagittal sinus The superior sagittal sinus (also known as the superior longitudinal sinus), within the human head, is an unpaired area along the attached margin of falx cerebri. This sinus runs the length of the falx cerebri.

Question 95

Question #130 : When performing MRI to rule out brain tumors, the weighted images acquired to evaluate the extent of lesion involvement, after injection of gadolinium, are:

Answer 95

T1 weighted When performing MRI to rule out brain tumors, the weighted images acquired to evaluate the extent of lesion involvement, after injection of gadolinium, are T1 weighted.

Question 96

Question #131 : If a 192 phase resolution is required, the TR must then be repeated _______ times (for 1 NEX).

Answer 96

192 If a 192 phase resolution is required, the TR must then be repeated 192 times (for 1 NEX).

Question 97

Question #132 : The phase encoding step is performed:

Answer 97

Prior to frequency encoding The phase encoding step is performed prior to frequency encoding.

Question 98

Question #133 : In what orientation would a tear of the collateral ligaments of the knee be best visualized?

Answer 98

Coronal Structures that lie medial and lateral, anatomically, are well visualized in the coronal plane. Therefore, the medial and lateral collateral ligaments of the knee are best visualized in the coronal plane.

Question 99

Question #134 : The optimal imaging plane for visualization of a TFCC tear is:

Answer 99

Coronal The Triangular FibroCartilage Complex (TFCC) of the wrist is best seen in the coronal imaging plane.

Question 100

Question #135 : On a T2 weighted image, edema appears bright because it has a _________ relaxation time.

Answer 100

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

Question 101

Question #136 : All of the following comprise the biliary tree EXCEPT:

Answer 101

Splenic duct

Question 102

Question #137 : What protocol would be selected to rule out islet cell tumor?

Answer 102

Pancreas Well or intermediately differentiated Pancreatic Neuroendocrine Tumors are sometimes called islet cell tumors, and are diagnosed with an abdominal MRI exam with attention to the pancreas.

Question 103

Question #138 : The common carotid artery bifurcates into the internal and external carotid artery at the level of the:

Answer 103

C3-4 disc space The common carotid artery bifurcation can be found at the level of the C3-4 disc space of the cervical spine.

Question 104

Question #139 : In order to acquire an intracranial arterial blood flow sequence, a presaturation pulse would be applied in which location?

Answer 104

Superior to slice group In order to acquire an intracranial arterial blood flow MRA, a presaturation pulse would be applied superior to the slice group in in order to null signal from intracranial venous blood flow.

Question 105

Question #140 : A major advantage of a 2D time of flight over a 3D time of flight sequence is the ability to:

Answer 105

Image larger areas without saturation of flowing blood 2D TOF is generally utilized when larger regions of anatomy are required to be imaged, with typically thicker slices than 3D TOF.

Question 106

Question #141 : 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:

Answer 106

Out of phase Out of phase TE's minimize signals from background stationary tissues in time of flight MR angiography.

Question 107

Question #142 : Phase contrast MRA techniques produce images in which the signal intensity within the vessel is dependent upon the:

Answer 107

Velocity of the flowing blood The velocity or speed of the vessel(s) of interest determines the signal intensities in phase contrast MR angiography (PCA).

Question 108

Question #143 : The first major branch of the abdominal aorta is the _______.

Answer 108

Celiac artery The first major branch of the abdominal aorta is the celiac trunk, which branches into the gastric, hepatic and splenic arteries.

Question 109

Question #144 : In a contrast enhanced MR angiography of the abdominal arteries, the IV gadolinium would enhance in which order?

Answer 109

Celiac, superior mesenteric, renal, inferior mesenteric The branches of the abdominal aorta, from proximal (superior) to distal are: Celiac, superior mesenteric, renal, and inferior mesenteric arteries.

Question 110

Question #145 : When imaging a geriatric patient, while performing a PCA MRA sequence, what imaging parameter might the operator adjust?

Answer 110

VENC VENC (velocity encodings) might be adjusted in an elderly (geriatric) patient during a PCA (phase contrast angiography) MRA sequence to compensate for changes in the rate of blood flow.

Question 111

Question #146 : The ligamentum flavum can be found in which part of the body?

Answer 111

Spine The ligamenta flava (singular, ligamentum flavum, Latin for yellow ligament) are ligaments which connect the laminae of adjacent vertebrae in the spine, all the way from the axis to the first segment of the sacrum (C2 to S1).

Question 112

Question #147 : On T1 weighted images of the spine, the CSF (cerebrospinal fluid) appears:

Answer 112

Hypointense to the spinal cord On T1 weighted images of the spine, the CSF (cerebrospinal fluid) appears hypointense (low signal intensity) to the spinal cord.

Question 113

Question #148 : In a cross sectional view of the MR magnet design, which coils are closest to the patient?

Answer 113

Radiofrequency coils The RF (radiofrequency) coils are closest to the patient, the primary component causing RF absorption in the patient

Question 114

Question #149 : The purpose of shimming the magnet is to:

Answer 114

Make the B0 field as homogenous as possible The additional magnetic fields (produced by shimming) add to the overall magnetic field of the superconducting magnet in such a way that the total B0 field becomes more homogeneous.

Question 115

Question #150 : The unit of measurement of the magnetic field surrounding the periphery of the MR scanner is expressed as:

Answer 115

Gauss The unit of measurement of the magnetic field surrounding the periphery of the MR scanner is expressed as Gauss.

Question 116

Question #151 : Active shielding can be defined as:

Answer 116

Superconducting windings within the MR scanner, reducing the fringe magnetic field Active shielding requires the implementation of superconducting windings within the construction of the MR scanner to oppose a portion of the magnetic field.

Question 117

Question #152 : ___________ 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.

Answer 117

Steel; passive Steel could be used to line the walls and/or floors of the MR magnet room to reduce the fringe field, and is defined as passive shielding.

Question 118

Question #153 : Which of the following has been documented to cause muscle contractions, cardiac arrhythmias, mild cutaneous sensations and visual light flashes?

Answer 118

Time varying magnetic fields (TVMF -- gradient) Time varying magnetic fields (TVMF -- gradient)have been documented to cause muscle contractions, cardiac arrhythmias, mild cutaneous sensations and visual light flashes.

Question 119

Question #154 : The gradient rise time is defined as the:

Answer 119

Time it takes for the gradient to reach its full amplitude The gradient rise time is defined as the time it takes for the gradient to reach its full amplitude.

Question 120

Question #155 : The gradient slew rate is the:

Answer 120

Rate of speed of ascent or descent of a gradient from zero to its maximum amplitude The gradient slew rate is defined as the rate of speed of ascent or descent of a gradient from zero to its maximum amplitude.

Question 121

Question #156 : Magnetic field inhomogeneity is expressed in:

Answer 121

Parts per million Magnetic field inhomogeneity is expressed in parts per million (ppm)

Question 122

Question #157 : A technique utilized to reduce the MRI scan time which requires the use of an array coil is:

Answer 122

Parallel imaging A recent development in MRI technology has been the development of sophisticated multi-element phased array coils which are capable of acquiring multiple channels of data in parallel. This 'parallel imaging' technique uses unique acquisition schemes that allow for accelerated imaging.

Question 123

Question #158 : What is the percentage of patients reported to have allergic reactions to gadolinium contrast agents?

Answer 123

1% Less than 1% patients are reported to have allergic reactions to gadolinium contrast agents during MRI procedures.

Question 124

Question #159 : 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.

Answer 124

16mL Divide 176 lbs by 2.2 (lbs per kg), then multiply the kg (80) by 0.2 ml/kg = 16mL

Question 125

Question #160 : To produce an image based on differences in T1, the time interval between 90° excitation pulses should be:

Answer 125

Short A short TR (time between excitation pulses) is necessary to produce an image based on differences in T1.

Question 126

Question #161 : All of the following are examples of INTRINSIC contrast parameters in tissues EXCEPT:

Answer 126

TR Intrinsic parameters in tissues are those that are specific to each tissue, inherent, and cannot be changed, such as ADC, T1/T2 time, specific proton density, and flow.

Question 127

Question #162 : Chemical or spectral fat suppression techniques suppress fat signal based on the:

Answer 127

Precessional frequency of fat Chemical or spectral fat suppression techniques suppress fat signal based on the precessional frequency of fat.

Question 128

Question #164 : Hemangiomas in the liver are typically benign lesions, and are best visualized with:

Answer 128

Delayed images Hemangiomas in the liver are typically venous-fed, benign lesions, and are best visualized with delayed enhancement images. Liver cancers, on the other hand, are typically arterial-fed and are best seen on first pass dynamic images.

Question 129

Question #165 : In an MRA sequence, the removal of signal from vessels is accomplished by:

Answer 129

Spatial presaturation In an MRA sequence, the removal of signal from vessels is accomplished by spatial presaturation.

Question 130

Question #166 : Which of the following, in an MRA sequence, aids in minimizing the loss of signal due to dephasing within a voxel:

Answer 130

C and D The longer the TE, the more time given for intravoxel dephasing, resulting in signal loss from within the vessel. Larger voxels lead to an increase in inhomogeneities within the voxel, increasing intravoxel dephasing and reducing signal intensity.

Question 131

Question #167 : Increasing the flip angle:

Answer 131

Increases SNR up to the Ernst angle Increasing the flip angle increases SNR up to the Ernst angle.

Question 132

Question #169 : Reducing the flip angle yields images with what change in image contrast?

Answer 132

Less T1 information Reducing the flip angle yields images with less T1 information.

Question 133

Question #170 : Reducing the TE yields images with what change in image contrast?

Answer 133

Decreased T2 information Reducing the TE yields images with decreased T2 information.

Question 134

Question #171 : The MRI system component that produces the magnetization of proton spins (alignment) is known as the:

Answer 134

Main magnet The MRI system component that produces the magnetization of proton spins (alignment) is known as the main magnet.

Question 135

Question #172 : The MRI system component that provides the ability to perform spatial encoding is the:

Answer 135

Gradient system The MRI system component that provides the ability to perform spatial encoding is the gradient system.

Question 136

Question #173 : In a superconducting magnet, the magnetic field strength is increased by increasing the:

Answer 136

Turns of wire In a superconducting magnet, the magnetic field strength is increased by increasing the turns of wire, current in the wires, or by reducing the spacing between the wires.

Question 137

Question #174 : Permanent magnets with a vertical magnetic field use surface coils that are:

Answer 137

Solenoids Permanent magnets with a vertical magnetic field use surface coils that are solenoids because the secondary magnetic field (B1)created by the RF coil must be perpendicular to the orientation of B0.

Question 138

Question #175 : The transmit bandwidth of the RF pulse affects:

Answer 138

A, B and D only The transmit bandwidth of the RF pulse affects the slice thickness, which has an effect on resolution and the overall SNR in the MR image.

Question 139

Question #176 : In order to generate thin slices, a ___________ is used. I. Steep slice selection gradient II. High amplitude slice select gradient III. Low amplitude slice select gradient IV. Narrow transmit bandwidth (tBW) V. Wide transmit bandwidth (tBW) VI. Narrow receiver bandwidth (rBW)

Answer 139

I, II and IV A thin slice thickness is achieved through the utilization of a steep, high amplitude slice select gradient, and a narrow transmit bandwidth (tBW).

Question 140

Question #177 : The receiver bandwidth (rBW) affects: I. Signal-to-noise ratio (SNR) II. Slice thickness III. Chemical shift IV. Spatial resolution

Answer 140

I and III only The receiver bandwidth (rBW) affects the signal-to-noise ratio (SNR) in the image, but also has an effect on chemical shift (decreasing the receiver bandwidth increases chemical shift)

Question 141

Question #178 : The B1 magnetic field is produced by a:

Answer 141

Radiofrequency coil The B1 magnetic field is produced by a radiofrequency coil.

Question 142

Question #179 : Shimming in MRI can be performed by all the following EXCEPT:

Answer 142

Turning the shim coil off and on rapidly Shimming in MRI can be performed by adding current to the gradient coils (gradient shimming), adding metal to different coils within the shim coil (passive shimming) or changing the current in the shim coil (active shimming)

Question 143

Question #181 : An adverse reaction or complication caused by treatment from a healthcare professional is called:

Answer 143

Iatrogenic An iatrogenic event or reaction is one caused by a medical professional, whether it be negligence, drug interactions, or even erroneous medical advice.

Question 144

Question #182 : The 2003 FDA revision on RF absorption limits the absorption to ______________ for the head.

Answer 144

3.0W/kg for 10 minutes The 2003 FDA revision on RF absorption limits the absorption to 3.0W/kg for 10 minutes for the HEAD.

Question 145

Question #183 : When imaging the spine, to rule out metastatic lesions of the spinal cord, contrast enhancement is used with T1 weighted images because:

Answer 145

Metastatic lesions (in the cord) enhance and normal cord does not When imaging the spine, to rule out metastatic lesions of the spinal cord, contrast enhancement is used with T1 weighted images because metastatic lesions (in the cord) enhance and normal cord does not.

Question 146

Question #188 : The difference in chemical shift is approximately ______ parts-per-million.

Answer 146

3.5 The difference in chemical shift is approximately 3.5 parts-per-million.

Question 147

Question #189 : A STIR sequence with a TI time of 160 ms will null signal from fat at what field strength?

Answer 147

1.5T The T1 time of fat at 1.5 Tesla is approximately 240 with a null point of 160 ms.

Question 148

Question #190 : Which of the following combinations of flip angle (FA) and TR would produce a T2 weighted gradient echo?

Answer 148

450 TR; 30º flip angle 450 TR; 30º flip angle combination would yield a T2 weighted gradient echo.

Question 149

Question #191 : To produce a high quality reformatted image, the:

Answer 149

Acquisition voxel should be isotropic To produce a high quality reformatted image, the acquisition voxel should be isotropic.

Question 150

Question #192 : 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:

Answer 150

Elliptic centric 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 k-space filling.

Question 151

Question #193 : During dynamic enhanced imaging for vasculature or visceral structures, contrast is administered and k-space is filled with __________ to ensure that the contrast enhancement is well visualized.

Answer 151

Centric

Question 152

Question #194 : ________ sequences use T1 gradient echoes with TR and FA selections to suppress signal from stationary tissues, visualizing flowing blood by flow-related enhancement, whereas __________ sequences use T2 gradient echoes with parameter selections that suppress stationary tissue and rely on velocity-induced phase shifts for vascular signal.

Answer 152

TOF MRA; PC MRA

Question 153

Question #195 : Which of the following best describes an EPI sequence?

Answer 153

A train of gradient echoes An EPI (echo planar imaging) sequences can be best described as a "train" of gradient echoes.

Question 154

Question #196 : Which of the following best describes an IR sequence?

Answer 154

A 180° pulse followed by a 90°/180° combination An IR (inversion recovery) sequence can be best described as a 180° pulse followed by a 90°/180° combination.

Question 155

Question #197 : Which of the following best describes a FSE sequence?

Answer 155

A train of spin echoes A FSE (fast spin echo) sequence can be best described as a "train" of spin echoes.

Question 156

Question #198 : Single order gradient moment nulling does not compensate for:

Answer 156

B and C - Single-order gradient moment nulling only compensates for first-order motion, such as flow with constant velocity.

Question 157

Question #199 : Reducing the FOV by a factor of 2 will reduce the voxel volume by a factor of:

Answer 157

4 Remember, the FOV is measured in phase and frequency dimensions, therefore reducing the FOV in half will reduce the phase AND frequency dimensions EACH by 2, for a total reduction of a factor of 4.

Question 158

Question #200 : Calculate the available imaging time for a patient with a heart rate of 90 beats/min, trigger window 15% and trigger delay of 80ms.

Answer 158

487 ms Heart Rate 90bpm, Trigger delay 50ms, Trigger window 10%, what is the available imaging time? 60000 ÷ 90 = 667ms. 667 – (100 <15% of 667> + 80 ---180) = 487 ms total available imaging time.