1. IMAGE QUALITY

2. SPATIAL RESOLUTION
CONTRAST RESOLUTION
RADIATION
DOSE
NOISE
IMAGE ARTIFACTS

3. Resolution in CT
Spatial Resolution
Contrast Resolution

4. SPATIAL RESOLUTION DEGREE OF BLURRING IN THE IMAGE
MEASURE OF THE ABILITY TO DISCRIMINATE OBJECTS OF
VARYING DENSITY A SMALL DISTANCE APART
AGAINST A UNIFORM BACKGROUND

5. MTF MODULATION TRANSFER FUNCTION
MOST COMMONLY USED TO DESCRIBE SPATIAL RESOLUTION IN CT

6. MTF MTF OF 1 – 100% TRANSFER OF OBJECT TO IMAGE

7. HIGH CONTRAST PHANTOM

10. FACTORS AFFECTING SPATIAL RESOLUTION
SLICE THICKNESS
FOCAL SPOT SIZE
DETECTOR WIDTH
TYPE OF CONVOLUTION FILTER (KERNEL)
MATRIX SIZE
FOV

11. SLICE THICKNESS S. RESOLUTION
5 MM
1 MM

12. FOCAL SPOT SIZE FOCAL SPOT SIZE S. RESOLUTION
LARGE FOCAL SPOT = LARGE PENUMBRA (BLURR)

13. DETECTOR WIDTH S. RESOLUTION

14. TYPE OF CONVOLUTION FILTER
SHARP KERNEL S. RESOLUTION
SMOOTH
SHARP

15. MATRIX SIZE S. RESOLUTION

16. DFOV SIZE
DFOV S. RESOLUTION
20CM
10CM

17. CONTRAST RESOLUTION SENSITIVITY OF THE SYSTEM LOW CONTRAST RESOLUTION
LOW CONTRAST DETECTIBILITY

18. LOW CONTRAST RESOLUTION ( TISSUE RESOLUTION)
THE ABILITY OF AN IMAGING SYSTEM TO DEMONSTRATE SMALL CHANGES IN TISSUE CONTRAST

19. CONTRAST RESOLUTION SENSITIVITY OF THE SYSTEM LOW CONTRAST RESOLUTION
LOW CONTRAST DETECTIBILITY

20. CONTRAST RESOLUTION PHANTOM

21. FACTORS AFFECTING LOW CONTRAST RESOLUTION
PHOTON FLUX
SLICE THICKNESS
PATIENT SIZE
DETECTOR SENSITIVITY
RECONSTRUCTION ALGORITHM
IMAGE DISPLAY
QUANTUM NOISE

22. PHOTON FLUX (INTENSITY)
PHOTON FLUX C. RESOLUTION
mAs P. FLUX
kVp P. FLUX

23. LOW TECHNIQUE
ADEQUATE TECHNIQUE

24. SLICE THICKNESS C. RESOLUTION
8 mm
5 mm

25. 10 mm – 100 PHOTONS
5 mm – 50 PHOTONS

26. PATIENT SIZE C. RESOLUTION
NORMAL
LARGE

27. DETECTOR SENSITIVITY C. RESOLUTION

28. TYPE OF CONVOLUTION FILTER
SMOOTH KERNEL C. RESOLUTION
SMOOTH
SHARP

29. MONITOR RESOLUTION C. RESOLUTION
IMAGE DISPLAY
MONITOR RESOLUTION C. RESOLUTION

30. QUANTUM NOISE C. RESOLUTION
HIGH NOISE
LOW NOISE

31. NOISE IN CT
FLUCTUATION OF CT# BETWEEN POINTS IN THE IMAGE FOR A SCAN OF UNIFORM MATERIAL SUCH WATER.

33. NOISE SOURCES IN CT QUANTUM NOISE – X-RAY INTENSITY AT THE DETECTORS
MATRIX SIZE
DFOV
SLICE THICKNESS
CONVOLUTION FILTER TYPE
PITCH

34. QUANTUM NOISE – CONTROLLED BY THE TECHNOLOGISTmA
Time
kVp
NOISE

35. NOISE QUANTUM (STATISTICAL) –CONTROLLED BY THE TECHNOLOGIST
ELECTRONIC – INHERENT IN THE EQUIPMENT

36. QUANTUM NOISE – CONTROLLED BY THE TECHNOLOGIST
DFOV
MATRIX
COLLIMATION
FILTER SPATIAL FREQUENCY
PITCH
NOISE

37. DOSE vs IMAGE QUALITY
RADIATION DOSE
IMAGE QUALITY