Instrumentation & Quality Assurance

Question 1

Which has an effect on the CRT appearance?

A) energy of isotope
B) dose calibrator
C) tag efficiency
D) count rate

Answer 1

D) count rate

Question 2

As septal length _____, septal penetration _____.

A) increases, increases
B) increases, decreases
C) decreases, decreases
D) decreases, increases
E) both B and D

Answer 2

E) both B and D

Question 3

The Z component of the signal in the photomultiplier tube will:

A) be processed by the pulse height analyzer
B) be recorded on the CRT
C) be removed by the PMT
D) all of the above

Answer 3

A) be processed by the pulse height analyzer

Question 4

Image exposure time may be determined by:

A) a present number of counts
B) a preset time
C) information density
D) all of the above

Answer 4

D) all of the above

Question 5

For a system with inverse gain control, and a gain setting of 4, each division on the pulse height analyzer dials corresponds to:

A) 0.5 keV/division
B) 1.0 keV/ division
C) 2.0 keV/division
D) none of the above

Answer 5

A) 0.5 keV/division

Question 6

For a system with true gain control, and a gain setting of 4, each division on the pulse height analyzer dial corresponds to:

A) 0.5 keV/division
B) 1.0 keV/ division
C) 2.0 keV/division

Answer 6

C) 2.0 keV/division

Question 7

What is the sensitivity of a camera that registers 28,137 cpm from a 120 uCi source is the background is 705 cpm?

A) 40 cpm/uCi 
B) 203 cpm/uCi 
C) 228 cpm/uCi 
D) 234 cpm/uCi 
E) 240 cpm/uCi

Answer 7

C) 228 cpm/uCi

Question 8

How often should the COR check be performed?

A) at least weekly
B) before each pt.
C) every 6 months
D) at least monthly

Answer 8

A) at least weekly

Question 9

The abbreviation COR stands for:

A) circle of rotation
B) center of region
C) correction of rotation
D) center of rotation

Answer 9

D) center of rotation

Question 10

What is the minimum number of counts that should be obtained in a uniformity correction flood for a SPECT camera?

A) 10 K
B) 10 million
C) 30 million
D) 60 million

Answer 10

C) 30 million

Question 11

Which of the following collimators will magnify an image?

A) flat field
B) diverging
C) converging
D) high resolution

Answer 11

C) converging

Question 12

Which of the following must be performed every 6 months at minimum?

A) COR
B) sealed source leak test
C) linearity of the dose calibrator
D) area survey of hot lab

Answer 12

B) sealed source leak test

Question 13

A dose calibrator must undergo repair or replacement if accuracy or constancy errors are:

A) present
B) greater than 5%
C) greater than 10%
D) grater than 20%

Answer 13

C) greater than 10%

Question 14

Accuracy of the dose calibrator must be tested:

A) on installation
B) at least annually
C) every 6 months
D) both A & B

Answer 14

D) both A & B

Question 15

Linearity of the dose calibrator must be checked:

A) on installation
B) quarterly
C) every 6 months
D) both A & B

Answer 15

D) both A & B

Question 16

Constancy of the dose calibrator must be tested:

A) daily
B) quarterly
C) weekly
D) every 6 months

Answer 16

A) daily

Question 17

A technologist wishes to evaluate the intrinsic uniformity of a camera used for planar imaging and is preparing a dose of 99mTc. How much activity is sufficient for the image?

A) 2 mCi
B) 200 uCi
C) 20 mCi
D) 10 mCi

Answer 17

B) 200 uCi