Ch 1

Question 1

Emission ct

Answer 1

Radiation source inside patient

Eg nuclear med

Question 2

Transmission ct

Answer 2

Radiation source is outside the patient

Question 3

Three steps formation of images by ct scanner

Answer 3

Data acquisition
Image reconstruction
Image display

Question 4

Data acquisition

Answer 4

Collection of X-ray transmission measurements from the patient

Question 5

Attenuation

Answer 5

Electronic detectors that measure transmission values

Question 6

Scanning

Answer 6

Process of translate into rotate stop rotate

Question 7

Volume scanning

Answer 7

Acquiring a volume of tissue during scanning

Question 8

Image reconstruction algorithm

Answer 8

Computer uses special mathematical techniques to reconstruct the ct image in a finite number of steps

Question 9

Ct communications

Answer 9

The electronic transmission of text data and images from the ct scanner to other devices such as laser printers, diagnostic workstations, display panels

Question 10

Ct process

Answer 10

When X-ray passes through patient through the patient they are attenuated and subsequently measured by detectors. The X-ray tube and detectors are inside the gantry of the scanner and rotate around the patient . Detectors convert the X-ray photons ( attenuation date) into electrical signals or analog signals which is converted into digital signal for input into computer. The computer then performs image reconstruction. The reconstructed image into its numerical is form and is converted for tech to view.

Question 11

Godfrey hounsfield and Allan cormack

Answer 11

Invented ct machine

Question 12

First ct date?

Answer 12

1971

Question 13

Developed first whole body ct? Year?

Answer 13

Robert Ledley

1974

Question 14

Pg 9 generations

Answer 14

G

Question 15

High speed ct

Answer 15

Created by dr Douglas Boyd

Used scan cardiovascular system without motion

Question 16

Spiral/ helical ct

Answer 16

Aka volume scanning

X-ray tube and detectors rotate 360 while patient and table move in and out of gantry

Created by dr willi kalender

Question 17

Multi slice ct scanners( Msct)

Answer 17

Multi detector tech that scanned four or more slices per revolution. Increases volume coverage speed

Question 18

Pitch

Answer 18

Ratio of the distance the table travels per revolution to the nominal beam collimating

Question 19

Isotropic resolution

Answer 19

Voxel perfect cube

Question 20

Dual source ct scanner

Answer 20

Two X-ray tubes and two detectors specifically to image cardiac patients in short time

Question 21

Three ways to reduce patient dose

Answer 21

• combined application to reduce dose
• ceramic detectors reduce dose by 25%
• online dose modulation , whereby the ma is optimized by to the patient characteristics to reduce dose

Question 22

Acr phantom

Answer 22

Has four sections can be imaged simultaneously to generate several test

Question 23

Ct Fluo principle

Answer 23

Depends on spiral helical data acquisition

Question 24

Ct fluro three advances

Answer 24

• fast continuous scanning made possible spiral/ helical principle
• fast image reconstruction
• continuous image display by use of cine mode at frame rates of two to eight images per second

Question 25

Rendering

Answer 25

Algorithms that help transform transaxial ct data into 3d

Question 26

Rendering steps

Answer 26

Volume formation
Classification
Image projection

Question 27

Volume visualization

Answer 27

Use of computer programs or visualization of tools that provide observer diagnostician with additional information from the image to facilitate diagnosis

Question 28

Ct angiography

Answer 28

Image blood vessels opacified

Question 29

Detectors two categories

Answer 29

Solid state detectors ( scintillation)

Gas ionization detectors ( xenon gas)

Question 30

Detectors used today

Answer 30

Gadolinium oxysulfide, ceramic, gemstone, ultrafast ceramic

Question 31

Image reconstruction

Answer 31

Mathematical construction of image to produce sharp, clear images of cross sectional anatomy