CBCT Basics

Question 1

Use of computers to generate multiple
images of an object from digitized density
information obtained from various signals; x
radiation (MDCT, CBCT), magnetic fields
(MRI), sonar radiation (ultrasound), etc.

Answer 1

Computed Tomography (CT)

Question 2

What are the 2 forms of Computed Tomography (CT)?

Answer 2

-CBCT (Cone Beam Computed Tomography)

–MDCT (Multi Detector Computed Tomography)

Question 3

Are most modern CBCT scanners Stand up/Sit down or lay down table?

Answer 3

Stand up/Sit down

Question 4

The lifetime of a CBCT unit is ~___-____ yrs

Answer 4

6 - 8 years

Question 5

Is there more or less radiation in CBCT than other forms of CT?

Answer 5

Less radiation

Question 6

What are the 4 factors affecting dose of CBCT?

Answer 6

• FOV
• Exposure
• Voxel
• Sensors

Question 7

What are the 2 factors of the cylinder of the CBCT affecting FOV?

Answer 7

Diameter

Height

Question 8

What are the 3 factors affecting exposure of CBCT?

Answer 8

kV
mA
Time

Question 9

Each “picture” taken by CBCT x ray is referred to as?

Answer 9

Basis image

Question 10

How many basis image captures are taken per CBCT?

Answer 10

100-600 basis images

Question 11

Number of basis images affects what 2 things about an image?

Answer 11

Quality

Dose

Question 12

___ is essentially a pixel viewed in 3 dimensions

Answer 12

Voxel

Question 13

A smaller voxel produces ______ resolution and _____ radiation dose

Answer 13

Better resolution; greater dose

Question 14

A smaller voxel leads to _____ image degradation

Answer 14

Greater degradation

Question 15

What is the main receptor used for CBCT that is smaller and cheaper whilst less sensitive to radiation? Also sharper image

Answer 15

Flat-panel detector

Question 16

The _______ images are the captures that allow us to get CBCT

Answer 16

Basis images

Question 17

– total set of basis images

Answer 17

Projection Data

Question 18

– image files

managed by image software

Answer 18

Volumetric Data Set