Image Production

Question 1

Collimation of the CT beam occurs:

Answer 1

At the xray tube and before the detectors

Question 2

The mathematical technique allowing the reconstruction of motion free images from helically acquired CT data is called

Answer 2

Interpolation

Question 3

Full width at half maximum of a CT scanner is used to describe

Answer 3

Spatial resolution

Question 4

A frist generation CT scanner consists of an xray tube and two detectors that translate across the patients head while rotating in one degree incriments for a total of ______ degrees.

Answer 4

180

Question 5

Windowing controls the _______.

Answer 5

Contrast and brightness

Question 6

Windowing controls the _______.

Answer 6

Contrast and brightness

Question 7

The loss of anatomic information between contiguous sections due to inconsistent patient breathing is called ______.

Answer 7

Misregistration

Question 8

A CT image is formed in part by projecting back all the attenuation values recorded during data acquisition onto a ______.

Answer 8

Matrix

Question 9

Areas of a CT image that contain abrupt changes in tissue density are electronically represented by which of the following?

1. Positive CT numbers
2. High spatial frequencies
3. Negative CT numbers
4. Low spatial frequencies

Answer 9

2. High spatial frequencies

Question 10

The size of a CT image displayed on a computer monitor can be enlarged by increasing the _____ _______.

Answer 10

Image magnification

Question 11

Multidetector CT systems typically employ which of the following detector geometries?

1. 1st generation
2. 2nd generation
3. 3rd generation
4. 4th generation

Answer 11

3. 3rd generation