quiz 5

Question 1

What best describes Temporal resolution?

Answer 1

Ability to distinguish structural differences over time

Question 2

If you increase the TR parameter what happens to your SNR.

Answer 2

Increases SNR while increasing scan time

Question 3

Increasing your TE has what affect on your SNR?

Answer 3

Decreases SNR however will increase T2 weighting improving contrast

Question 4

When increasing FOV what happens to signal to noise?

Answer 4

Increases

Question 5

Which would have an increase in SNR, a large or small pixel?

Answer 5

Large

Question 6

If you increase the receive bandwidth what affect will this have on SNR?

Answer 6

Decrease

Question 7

Would a large or small surface coil provide better SNR.

Answer 7

small

Question 8

Which provides better spatial resolution a square or rectangular pixel?

Answer 8

square

Question 9

If you use a rectangular FOV to fit the anatomy but the Pixel remains square does this have a noticeable change in spatial resolution.

Answer 9

no

Question 10

If you use a rectangular FOV to fit the anatomy but the Pixel remains square what affect will this have on scan time?

Answer 10

decrease

Question 11

A broad receive bandwidth will contain more noise than a narrow bandwidth.

true/false

Answer 11

True

Question 12

The best way to improve SNR is by increasing your NSA (NEX)

true/false

Answer 12

false

Question 13

Flip angles less than 90 degrees offer a larger amount of transverse magnetization thus increasing signal amplitude(max siganal).

true/false

Answer 13

false

Question 14

To determine voxel volume you need the pixel dimensions and the slice thickness to determine volume.

true/false

Answer 14

atrue

Question 15

Increasing slice thickness from 5mm to 10mm with increase SNR

true/false

Answer 15

true

Question 16

The signal to noise ratio is….

Answer 16

The ratio of the amplitude of the received to the average amplitude of noise

Question 17

Which would have a greater SNR.

Answer 17

a pixel dimension of 10mm x 10mm with 8mm slice thickness

Question 18

The parameter allows us to saturate bound Protons to increase signal in the free protons.

Answer 18

MTC

Question 19

This is responsible for determining the amount of T2 weighting.

Answer 19

TE

Question 20

The two parameters are responsible for the amount of T1 and PD weighting.

Answer 20

TR

Flip Angle

Question 21

PD in the tissues being imaged determines the amplitude of signal received.

true/false

Answer 21

true

Question 22

Would Lung tissue or tissues in the pelvis have a higher amplitude of proton density?

Answer 22

pelvis

Question 23

Coil selection and placement play a role in both SNR and CNR.

true/false

Answer 23

true

Question 24

An image of the liver that has high CNR but low SNR is of little or no diagnostic value

true/false

Answer 24

false

Question 25

An image with a rectangular FOV and rectangular pixels would have the same spatial resolution as an image with the same rectangular FOV and

true/false

Answer 25

false