Digital ImagingDigital Imaging
Digital ImagingDigital Imaging
acronyms
1.PSP
2.CRT
3.ADC
4.IP
5.CR
6.DR
7.PACS
8.SNR
9.CNR
10. CCD
11. FOV
12. LUT
13. DICOM
14. RIS
15. HIS
16. TFT
17. DQE
18. DAP
19. DEL
20. Voxel
1.Photostimulable phosphor-europian activatedbarium fluorohalide (=200 speed)
2. Cathode-ray tube or computer monitor
3.Analog to digital converter
4.Imaging plate
5.computed
6./digital radiography
7.Picture archiving communication systems
8.SIGNAL TO NOISE RATIO PG 410 –BUSHONG The higher the signal theless the noise.
9.CONTRAST TO NOISE RATIO can be manipulated until noisebecomes too apparent-limited by the SNR
10.Charge coupled device- crystal silicon- small, replaces vidicon influoro, device used in DR
11.Field of View –how much of the patient is imaged in the matrix
12.Look up Table – plotting grays on a scale
13.Digital imaging and communications in medicine -blending PACSand other imaging modalities
14.Radiology Information system
15.Hospital Information system
16.Thin Film Transmitters- indirect conversiondetector in DR. Stores electronic charge (from converted light)before computer processes it.
17.Detective Quantum Efficiency converting x-rayintensities into a radiographic image
18.DAP-Dose Area Product-multiplication of the dose and thearea exposed
19, DEL- Detector Element. -size of the TFT..smaller-betterresolution
20. Voxel-tissue volume
16.NYQUIST-Sampling frequency of digital data
20.Voxel-tissue volume
X,y and z lines
NYQUIST-Sampling frequency of digital data
Z line
X line
y line
•Computers connected together in ahospital by LAN
•Outside computers connected tohospital server by VPN
INDIRECT LAYERING
•FLUORESCENT (ONLY ININDIRECT-WHY?)
•PHOTODETECTOR LAYER
•TFT
•AMORPHOUS SILICON-RELEASESELECTRONS WHEN STRUCK BYLITE (INDIRECT)
•AMORPHOUS SELENIUM-RELEASES ELECTRONS WHENSTRUCK BY X-RAY PHOTONS(DIRECT)
FOV/MATRIX/PIXEL
•FOV can increase without change toMatrix or Matrix can change w/ochange to FOV –
•What about the pixel?
Question?
•Does the pixel size change if theFOV changes and the matrix staysthe same? Or what if the matrixchanges but the FOV stays thesame?
•If the FOV increases and the matrixstays the same, the pixel sizeincreases