CT Flashcards
1
Q
What is CT?
A
- utilises an x-ray tube and a detector array rotating around the patient
- data collected is reconstructed into sectional/axial images
2
Q
What are the components of a CT?
A
- gantry
- table
- control console
- image processing
3
Q
What are types of scans?
A
- helical
- multi-slice
- sub-second
- CTA possible
4
Q
What is algorithm and kernel?
A
- mathematical approach to data representation in image
- manipulaition of actual data
5
Q
What is the standard CT window for cerebral tissue?
A
- WW: 100-150
- WL: 40-60
6
Q
What is the standard CT window for bone?
A
- WW: 2000-3000
- WL: 300-400
7
Q
What is the standard CT window for lung?
A
- WW: 1500
- WL: -600
8
Q
What is the standard CT window for mediastinal tissue?
A
- WW: 300-800
- WL: 50-80
9
Q
On a unenhanced scan what low density lesions are seen?
A
- ventricular density (cyst, centricular obstruction)
- oedema (abscess or infarct)
10
Q
On a unenhanced scan what high density lesions are seen?
A
- calcification
- haemorrihage
11
Q
What are some data management challeneges?
A
- post processing slice width
- mutliplanar reconstruction
- shaded surface display
- volume rendering
12
Q
What is the role of CT in oncology?
A
- diagnosis
- staging TNM
- simulation for planning
- guidance for intervention
- monitoring response of treatment
- consider protocols
13
Q
What are some scanning parameters?
A
- scan plane/ patient position
- exposure factors
- pitch
- slice thickness
- scan extent
- table position and image orientation
- scan time
- subject contrast
- scan speed with respect to contrast
