CT Quiz 2/12/15 Flashcards Preview

spring 2015 > CT Quiz 2/12/15 > Flashcards

Flashcards in CT Quiz 2/12/15 Deck (12):
0

Picture element an individual matrix box in each ____ is assigned a CT number

Pixel

1

A series of rows and columns of pixels that give the form to the digital image

Matrix

2

A 3D tissue volume, height, width and dept of each pixel represents a ____ when viewing an image

Voxel

3

The center value of the window width (Center Value)

Window level

4

(Amount of contrast) mechanism that determines the quantity of HU or the range of CT numbers used to map signals into shades of gray for specific images

Window width

5

Specific numbers are assigned to individual pixels within the image data set based on the type of material image

Hounsfield unit

6

Determines the number of detector cells in which the raw data will be acquired (isocenter is very important)

Scan field of view

7

It determines how much and what section of the collected raw data are used to create an image
◾️zoom or target
◾️data for display on the image

Display field of view

8

Begins with one or more images. the tube and detector remain stationary while the patient moves.

Localizer scanner

9

Table remains stationary while the x-ray tube rotates within the gantry but with a pause as table moves to the next location
◾️ optimal resolution
◾️ usused when speed Is not a concern

Axial (step and shoot) scanning

10

Continuous movement of the table through the gantry and the x-ray tube remains on for an extended time

Helical or spiral scanning

11

Unknown point falls between two straight lines

Interpolation