Week 4

Question 1

The path of the x-ray beam as it enters and exits the patient.

Answer 1

Projection

Question 2

A path of an individual photon from the x-ray tube to the detector.

Answer 2

Ray

Question 3

Individual measurement of beam attenuation

Answer 3

Ray sum

Question 4

Combined attenuation properties of each ray sum cross-referenced with their respective positions.

Answer 4

Attenuation profile

Question 5

A complete set of ray sums collected from multiple angles.

Answer 5

View

Question 6

Information from all of attenuation profiles projected onto a matrix

Answer 6

Image

Question 7

Interpolation is necessary because:

Answer 7

it allows the viewer to observe the images in a flat plan

Question 8

a mathematical technique used to estimate the value of a function from known values on either side of the function.

Answer 8

Interpolation

Question 9

Determines the total area scanned

Answer 9

Scan field of view (SFOV)

Question 10

Ability to merge image data from overlapping acquisition data sets

Answer 10

Interlaced sampling

Question 11

The relationship between DFOV and pixel size is:

Answer 11

Direct

Question 12

The relationship between matrix and pixel size is:

Answer 12

Inverse

Question 13

Adjusting the window width changes the ______ of an image.

Answer 13

Contrast

Question 14

Adjusting the window level changes the ______ of an image.

Answer 14

Brightness

Question 15

A disadvantage of performing image reformatting is the:

Answer 15

loss of image detail

Question 16

MIPs, or maximum intensity projections, are created using only the ______ Housfield units and filtering out the rest

Answer 16

highest

Question 17

T/F: Multiplanar reconstruction does not add additional information to the data set, just presents it in a new way.

Answer 17

True

Question 18

The central database for receiving and storing image data is called:

Answer 18

PACS

Question 19

T/F: The Hounsfield scale represents the range of contrast allowed to be administered in a scan

Answer 19

False

Question 20

Subject scan data to mathematical processes

Answer 20

Kernels

Question 21

Most modern CT scanners use ___ degree linear interpolation because:

Answer 21

180; increases spatial resolution

Question 22

Difference from one slice to the next

Answer 22

Pitch

Question 23

Size of reconstructed area on the monitor after the patient has been scanned

Answer 23

Display field of view (DFOV)

Question 24

Scans requiring fewer shades of grey (brain)

Answer 24

Narrow WW