DEXA Flashcards
1
Q
Ads/Disads of Pencil Beam
A
+ Single detector
+ High precision
- Long scan time
2
Q
Ads/Disads of Wide-Angle Fan Beam
A
+ Multiple detectors
+ Shorter scan times
- Magnification distortion
3
Q
Ads/Disads of Narrow Angle Beam
A
- Precision of Pencil
- Speed of Fan
- 3rd Gen. beam technology
- Acquisition of multiple images
4
Q
What is Dual Energy X-ray Absorptiometry?
A
- Bone isolated from soft tissue attenuation using pencil/fan beam
- Denser the bone fewer X-ray photons transmitted to detector
- Info extracted for data analysis
- Photons transmitted are measured against standards for young healthy adults
5
Q
What does a T-Score measure?
A
Bone density of healthy average person
6
Q
What does Z-Score measure?
A
Bone density of same age/gender
7
Q
What do the Fan and Pencil beams require
A
Linear displacement of detector moving across with C-arm
8
Q
What do the 2 beams provide
A
X-ray photons of 2 energies from different sources at set frequencies
Results from photons hitting detectors
