FREE AND STUDY GAMES ABOUT MRI FORMULAS EXAM

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FREE AND STUDY GAMES ABOUT MRI FORMULAS EXAM

QUESTIONS

Actual Qs and Ans Expert-Verified Explanation

This Exam contains:

-Guarantee passing score -19 Questions and Answers -format set of multiple-choice -Expert-Verified Explanation

Question 1: TR X Phase Matrix X NEX X # of slices

Answer:

Gradient Echo 3D acquisition

Question 2: FOV? matrix

Answer:

Pixel size Question 3: 3D sequence scan time : TR x Phase Matrix x NSA/NEX x # Slices = 3D Scan Time, ÷ 1000

Answer:

Scan time: 3D Gradient Echo

Question 4: FOV ÷ phase matrix = phase dimension pixel FOV ÷ frequency matrix = frequency pixel

Answer:

Pixel Size Dimensions (phase and frequency)

Question 5: SNR increase calculated by the square root (?) of the increase

Answer:

NSA/NEX and SNR

Question 6: TR X Phase Matrix X NEX

Answer:

Spin Echo

Question 7: FOV ? Matrix (phase and frequency) ? slice thickness measurement

Answer:

Voxel size Question 8: Effective TR (see above) - (delay and trigger window). For example, Heart Rate 80bpm, Trigger delay 50ms, Trigger window 10%, what is the available imaging time? 60000 ÷ 80 = 750ms. 750 - 125 (75{10% of 750} + 50{delay}=125) = 625 ms total Imaging time

Answer:

Calculate available imaging time in a Cardiac MR Rate

Question 9: TR X Phase Matrix X NEX X ETL

Answer:

Fast Spin Echo Question 10: Multiply phase pixel size x frequency pixel size = Pixel area (answer squared 2)

Answer:

Pixel Area

Question 11: FOV ÷ Matrix = pixel size

Answer:

Pixel Size

Question 12: Pixel area X slice thickness

Answer:

Voxel volume

Question 13: Pixel area x slice thickness = Voxel volume (answer cubic 3)

Answer:

Voxel volume

Question 14: TR X Phase Matrix X NEX

Answer:

Gradient Echo (assuming 2D)

Question 15: Decreasing BW by factor of 2 increases SNR by ?2

Answer:

Bandwidth and SNR Question 16: 60,000 ÷ heart rate (60 seconds per minute, 1000 milliseconds per second)

Answer:

Calculate effective TR Question 17: Fast Spin Echo Sequence : TR x Phase Matrix x NEX ÷ ETL, ÷ 1000 to convert to seconds

Answer:

Scan time: Fast Spin Echo

Question 18: TR x Phase Matrix x NSA/NEX = Scan Time in a Spin Echo sequence, Divide by 1000 to convert ms (milliseconds) into seconds

Answer:

Scan time: Spin Echo

Question 19: Reducing the FOV decreases SNR by a factor of the FOV2. Example: Reducing the FOV from 40cm to 20cm results in SNR reduced to 1?4 the original SNR, due to the voxel volume being reduced by a factor of 4

Answer:

FOV and SNR