1.  Diah Ayu Kurniasari
 Lirih Widiowati
 Tito Aditya Resmana
 Titi Erika Wulandari

2. Digital Radiography
 Computed radiography, CR
 Direct radiography or direct digital
radiography, DR
 Digital subtraction angiography, DSA

3. Computed Radiography (CR)
is the generic term applied to an imaging system
comprised of:
★Photostimulable Storage Phosphor
to acquire the x-ray projection image
★ CR Reader
to extract the electronic latent image
★ Digital electronics
to convert the signals to digital form

4.  Computed Radiography (CR) uses very
similar equipment to conventional
radiography except that in place of a film to
create the image, an imaging plate (IP) is
used. The imaging plate is placed under the
object to be examined and the x-ray
exposure is made.

5. X-rays
Conventional radiography
Screen-film combination
IP only
Cassette

6. CR Detector
• Photostimulable Storage Phosphor (PSP)
• BaFBr compound, Eu activated
Phosphor Plate
Or imaging plate”IP” Cassette Holder
Barium fluorin bromide Eu: europium

7.  instead of taking an exposed film into a
darkroom for developing in chemical tanks or
an automatic film processor, the imaging
plate is run through a special laser scanner
to read and digitize the image.

9. Computed Radiography “reader”
Plate stacker
Information panel

13.  The CR imaging plate contains
photostimulable storage phosphors, which
store the radiation level received at each
point in local electron energies. When the
plate is put through the scanner, the
scanning laser beam causes the electrons to
relax to lower energy levels, emitting light
that is detected by a photo-multiplier tube
(PMT), which is then converted to an
electronic signal.

14. photo-multiplier tube

17. POST-PROCESSING

19.  The digital image can then be viewed
and enhanced using software that has
functions very similar to other
conventional digital image-processing
software, such as contrast, brightness,
filtration and zoom.

26. GA GT GC GS RN RT RE
影像 A 1.2 E 1.6 -0.14 4 R 0.5
影像 B 0.9 A 1.6 -0.42 4 R 4.0

27. GA GT GC GS RN RT RE
影像 A 1.0 F 0.7 0.38 4 R 0.5
影像 B 1.0 A 0.7 0.10 4 R 5.0

28. GA GT GC GS RN RT RE
影像 A 1.4 0 1.6 0.7 4 Q 1.1
影像 B 0.9 A 0.8 0.0 4 Q 5.0

29. GA GT GC GS RN RT RE
影像 A 0.6 0 0.6 0.63 5 T 0.5
影像 B 0.9 A 0.6 0.20 5 T 5.0

30. GA GT GC GS RN RT RE
影像 A 0.9 E 1.6 -0.16 4 R 0.5
影像 B 0.7 A 1.5 -0.58 4 R 5.0
影像 C -1.3 A 1.5 0.66 4 R 5.0

31. Subtraction

37. Disadvantages
 Imaging plates (IP's) are quite expensive
and can be easily damaged, if the
system being used requires manual
handling of the IP's. Theoretically, IP's
may be reused thousands of times, but
constant use will always result in
damage to the IP and image artifacts.