Advanced MR Imaging

Question 1

The HEIGHT of a peak on an MR spectrum correlates to the _________ of a substance that was detected

Answer 1

Amount

Question 2

Which of the following is NOT a metabolite found in a 1H spectrum of normal brain tissue?

Answer 2

Succinylcholine

Question 3

The final result in a spectroscopy study is:

Answer 3

A spectrum of specific detected metabolites

Question 4

Contrast in Diffusion Weighted Imaging (DWI) depends on:

Answer 4

The degree to which molecular mobility is impaired (water restriction)

The sensitivity of the sequence to Brownian motion

The direction of water diffusion

Question 5

Common problems in DWI include

Answer 5

Bulk patient motion

Low signal-to-noise ratio

Sensitivity to magnetic susceptibility when using echo planar readout

Question 6

: In DWI sequences, ADC stands for:

Answer 6

Apparent Diffusion Co-efficient

Question 7

The final result in a perfusion study is:

Answer 7

A set of calculated images which indicate various flow characteristics

Question 8

: ____________ can be described as water molecules moving the same way in every direction.

Answer 8

Isotropic diffusion

Question 9

____________ can be described as water molecules moving in a preferred direction

Answer 9

Anisotropic diffusion

Question 10

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

Question 11

Image 80 is an example of:

Answer 11

Single voxel spectroscopy

Question 12

Letter A in Image 80 is pointing to the:

Answer 12

Amount of the substance/metabolite detected

Question 13

Letter B in Image 80 is pointing to the

Answer 13

Frequency of the substance/metabolite detected

Question 14

Image 81 is an example of:

Answer 14

Multi voxel spectroscopy

Question 15

Letter A in Image 81 is pointing to the

Answer 15

Amount of the substance/metabolite detected

Question 16

Image 81’s acquisition required the use of IV gadolinium contrast to obtain the image

Answer 16

False

Question 17

Image 93 is an example of:

Answer 17

Diffusion tensor imaging

Question 18

: Image 94 is an example of

Answer 18

Diffusion tensor imaging (tractography)

Question 19

Image 95 is an example of:

Answer 19

Diffusion tensor imaging (tractography)

Question 20

Image 96 is an example of:

Answer 20

Diffusion tensor imaging (tractography)

Question 21

Image 97 is an example of

Answer 21

MR perfusion

Question 22

Image 97 required the use of IV gadolinium contrast to obtain the image and data shown?

Answer 22

True

Question 23

: Image 98 is an example of

Answer 23

MR perfusion

Question 24

The echoes collected from a 256/256 Sagittal Cervical spine have a frequency range 14.1 kHz above and below the central frequency, 1.5Tesla system with 220 Hz chemical shift between fat and water, the vertebral body signal will shift _____ pixels relative to the signal in intervertebral disk

Answer 24

2. 0
3. 2 x 1000 = 28200 Hz; 28200 ÷ 256 = 110; 220 ÷ 110 = 2 pixels shift between fat and water

Question 25

What would the pixel shift be in a sequence acquired at 1.5Tesla (220 Hz) with a 224 matrix and a BW of 26.8 kHz?

Answer 25

1.8
26.8(bandwidth in kHz) x 1000 to convert into Hz = 26800
26800 ÷ 224(matrix) = 120 Hz frequency difference per pixel
220(chemical shift) ÷ 120 = 1.8, the fat image will be shifted 1.8 pixels along the frequency/readout axis relative to water