Data Types

Question 2

Data Types

Answer 2

1. Raw Data
2. Image Data

Question 3

Unprocessed numerical information collected by the detectors during the scan

Answer 3

Raw data

Question 4

Represents the XR attenuation measurements from many angles around the pt

Answer 4

Raw data

Question 5

Used by the CT computer and reconstruction algorithms (eg FBP or Iterative Reconstruction) to create the final image

Answer 5

Raw data, Function/ Role

Question 6

Serves as the foundation for generating image data

Answer 6

Raw data, Function/ Role

Question 7

Stored in the computer’s RAM or hard disk temporarily. Not directly viewable on the monitor

Answer 7

Raw data, Characteristics

Question 8

Very large in file size. Can be reprocessed to imporve image quality or change parameters

Answer 8

Raw data, Characteristics

Question 9

Processed and reconstructed form of raw data (final digital image displayed on the CT console or PACS)

Answer 9

Image data

Question 10

Represents the calculated attenuation coefficients of each voxel (volume element) within the scanned area

Answer 10

Image data

Question 11

Used for diagnostic viewing, post-processing, and archiving

Answer 11

Image data, Function/ Role

Question 12

Can be enhanced through windowing, 3D rendering, or MPR

Answer 12

Image data, Function/ Role

Question 13

Smaller in size compared to the other data type. Can be viewed, printed, and t ransferred to PACS

Answer 13

Image data, Characteristics

Question 14

Cannot be reprocessed to change reconstruction algorithm. Contains CT numbers representing tissue densities

Answer 14

Image data, Characteristics

Question 15

Single, straight XR path that travels from the XRT, passes through the pt’s body, and is detected by a corresponding detector element on the opp side

Answer 15

Ray

Question 16

Records a single attenuation measurement (how much the XR beam was weakened by tissues it passed through)

Answer 16

Ray

Question 17

Contributes one data point used in reconstructing the brightness (CT number) of individual pixels in the final image

Answer 17

Ray

Question 18

A collection of all rays taken at one specific angle of the XRT around the patient

Answer 18

Views

Question 19

If the CT tube rotates to 1 position and sends out 1,000 rays that are detected

Answer 19

One view

Question 20

The systen will then rotate slightly and take another set - forming many views during one full rotation (typically hundred to thousands)

Answer 20

Views

Question 21

Represents the set of attenuation values (data) recorded from one view - essentially the output of all rays from that angle

Answer 21

Profile

Question 22

Appears as a graph or data line showing signal intensity (detector response) verseus detector position

Answer 22

Profile

Question 23

Each — is one row of data used to create a sinogram

Answer 23

Profile

Question 24

A pattern that contains all raw data from all views

Answer 24

Sinogram

Question 25

The sinogram is later mathematically backprojected to reconstruct the image

Answer 25

Profile