MRI in Practice: Ch 4 Parameters and Trade-Offs Flashcards
For a FSE sequence what is the scan time formula?
scan time = (TR x Phase Matrix x NEX)/ ETL
What is a benefit of increasing TR?
a. Decreases T1 weighting
b. Increases SNR
c. decreases slices
d. decreases scan time
b. Increases SNR
What is a limitation of increasing TR?
a. Decreases T1 weighting
b. Increases SNR
c. decreases slices
d. Increases scan time
d. increases scan time
What happens to SNR when TE is increased?
a. Increases
b. decreases
c. remains the same
decreases
Which of the following is a benefit of increasing NEX?
a. Decreases T1 weighting
b. Increases SNR
c. decreases slices
d. increases scan time
increases SNR
How does increasing slice thickness affect SNR?
a. it increases
b. it decreases
c. no change apparent
it increases
How does increasing slice thickness affect resolution?
a. it increases
b. it decreases
c. no change apparent
It decreases
How does increasing only the FOV affect resolution?
a. it increases
b. it decreases
c. no change apparent
It decreases
How does increasing only the FOV affect SNR?
a. it increases
b. it decreases
c. no change apparent
a. it increases
How does increasing only the FOV affect scan time?
a. it increases
b. it decreases
c. no change apparent
no change apparent
How does increasing the FOV affect aliasing?
a. it increases
b. it decreases
c. no change apparent
It decreases
How does increasing the phase matrix affect resolution?
a. it increases
b. it decreases
c. no change apparent
it increases
How does increasing the phase matrix affect scan time?
a. it increases
b. it decreases
c. no change apparent
it increases
How does increasing the receive bandwidth affect chemical sift?
a. it increases
b. it decreases
c. no change apparent
it decreases
How does increasing the receive bandwidth affect SNR?
a. it increases
b. it decreases
c. no change apparent
It decreases
