Week 13 - Quality Control

Question 1

What are the 3 fundamental steps of QC?

Answer 1

-acceptance testing
-routine performance evaluation
-error correction

Question 2

Who is acceptance testing completed by?

Answer 2

Qualified medical physicist

Question 3

Who is routine performance testing performed by primarily?

Answer 3

The technologist

Question 4

What are the test priority classifications?

Answer 4

Essential
Desirable

Question 5

Indicates that performance must be within certain tolerances, and if it is not, the equipment should not be used

Answer 5

Acceptable

Question 6

Indicates the level of performance that should be attained under favourable circumstances, which is the level at which a facility should work if feasible

Answer 6

Achievable

Question 7

How often should a visual inspection be done?
-xray beam window
-table position
-height indicator
-WW/WL display
-high voltage cables

Answer 7

Weekly
By tech

Question 8

T/F
CT tech must be able to identify and correct image artifacts from water phantom on daily basis
-linear artifact
-streak artifact
-ring artifact

Answer 8

True

Question 9

What is the SC35 limit for CT number and standard deviation?

Answer 9

SC35: 0+- 4HU

Question 10

How is high contrast resolution measured?

Answer 10

1. MTF Curve (recommended)
2. Bar pattern test device
3. Visual assessment

Question 11

-test device is a high contrast wire (2mm)
-measurement of the 50% and 10% point of the MTF curve must be within 0.5lp/cm or
+- 15% of established baseline value
-done by medical physicist

Answer 11

MTF curve test

Question 12

-quantitative measurement
-line pair patterns of different frequencies
-the limiting high contrast resolution should be 5 lp/cm or more

Answer 12

Bar pattern test device

Question 13

-high contrast resolution must be 1mm or less

Answer 13

Visual assessment