Practice Questions (Due October 13th)

Choose the best response for each of the following statements.

For a sagital MR image of the lumbar vertebrae this is the gradient that is used for frequency encoding.

1. X
2. Y
3. Z

For an axial examination of the lungs this gradient would be used for phase encoding.

1. X
2. Y
3. Z

This is controlled by the slope of the slice select gradient.

1. Image matrix
2. Slice Thickness 
3. Field of View

This is the precessional frequency of hydrogen when the field strength of the magnet is 10,000 Gauss.

1. 21.28 MHz
2. 42.57 MHz
3. 63.86 MHz
4. 10,000 MHz

This is one way of achieving a thin slice in MRI. (reduce slice thickness).

1. use a steep slice select gradient slope
2. use a broad transmit bandwidth.
3. use a narrow receive bandwidth.
4. Both A and C

This gradient is switched on during the collection of the MR signal (during the echo)

1. slice select gradient
2. phase encoding gradient
3. frequency encoding gradient

Fill in the blanks with X, Y or Z based on the correct gradient.

 

Procedure            Slice Selection     Phase Encoding     Frequency Encoding

 

Sag. Knee

 

Coronal neck

 

Axial Lumbar

 

Sag. T. Spine