Computed Tomography Image Quality

5 Characteristics In Image Quality

The factors that influence picture quality;

1. Characteristic X-rays
2. Dose
3. Subject transmission
4. Slice thickness
5. Scatter
6. pixel Size
7. reconstruction algorithm
8. display resolution

Parameters for measuring image quality

PSF : Point Spread Function

LSF : Line Spread Function

CTF : Contrast Transfer Function

MTF : Modulation Transfer Function

SPATIAL RESOLUTION

A measure of the ability to discriminate objects of varying density a small distance apart against a uniform bacground (Computed Tomography, Seeram, 2001 p.176)

Factors affecting the spatial resolution

1. geometry :Are factors that are directly related to the acquisition of data such as focal spot, detectors, isosenter
2. reconstruction Algorithm A factor related to the mathematical process backprojection and convolution.

Contrast Resolution

The ability to show a small object with a variety of 2-3mm a very low density.
Compared to conventional radiography in CT contrast resolution better

Factors affecting Contrast Resolution.

Slice thickness
Patient size
Sensitifitas detektor
Rekonstruksi algorithma
Image display
Image recording
Noise

ct scan abdomen Tags: Computed Tomography Image Quality