COMPUTED RADIOGRAPHY

1. COMPUTED RADIOGRAPHY Dawn Guzman Charman, M.Ed., R.T. RAD TECH A

2. filmless’ radiology departments Diagnostic radiographers have traded their film and chemistry for a computer mouse and monitor advance for Rad Sci Prof, 8/9/99

3. Digital imaging is the acquisition of images to a computer rather than directly to film. What Is Digital Imaging?

5. New Technology • Has impacted • practicing radiologic technologist • educators • Administrators • students in the radiologic sciences.

6. Many local area hospitals • and medical centers • have this equipment NOW

7. Computed Radiography Fundamentals of Computerized Radiography

8. CR SYSTEM COMPONENTS • CASSETTES (phosphor plates) • ID STATION • IMAGE PREVIEW (QC) STATION • DIGITIZER • VIEWING STATION

9. COMPUTED RADIOGRAPHY Medical Imaging is changing “FILMLESS” Radiology is the future And the Future is here! El Camino College First educational institution in California or across the country to offer this new technology on a college campus

10. Equipment Costs Don Visintainer successfully wrote grants, and received funding from VTEA, P4E, and private sources Total $410,916.00 + HIDDEN COSTS *

11. History of CR • INDUSTRY • Theory of “filmless radiography” first introduced in 1970 • 1981 Fugi introduced special cassettes with PSP plates (replaces film) • Technology could not support system • First clinical use in Japan - 1983

12. Predictions • 1980 – Bell Labs believed that Unix would be the worlds dominant operating system • 1982 – Bill Gates thought 640K of main memory would suffice for workplace operating systems ( This presentation is 80,000 kb) • 1984 – IBM predicted that personal computers would not amount to anything

13. History of CR • By 1998 – over 5000 CR systems in use nationwide • 1998 – Local area hospitals begin to incorporate CR systems in their departments • (Riverside Co. Hosp builds new hospital in Moreno Valley) – completely CR system – 1st generation equipment

14. TERMINOLOGY • F/S - Film/Screen (currently used method) • CR - Computed Radiography • DR - Digital Radiography • DDR - Direct to Digital Radiography

15. IMAGE CREATION • SAME RADIOGRAPHY EQUIPMENT USED • THE DIFFERENCE IS HOW IT IS CAPTURED • STORED • VIEWED • And POST -PROCESSED

16. CONVENTIAL vs DIGITAL IMAGING • Currently, most x-ray imaging systems produce an analog image (radiographs, & fluoroscopy). • Using x-ray tube – films in cassettes

17. CONVENTIAL vs DIGITAL IMAGING • Digital radiography systems require that the electronic signal be converted to a digital signal – • Using x-ray tube – cassettes with phosphor plate OR • DR systems - transistors

18. COMPUTED RADIOGRAPHY & DIRECT RADIOGRAPHY& FILM SCREENIMAGE CAPTURE FS - Film inside of cassette CR - PHOTOSTIMULABLE PHOSPHOR PLATE DR(DDR) - TFT (THIN FILM TRANSISTOR)

19. Cassette w/ film CR w psp plate

21. Directed Digital Radiography(DDR) Directed digital radiography, a term used to describe total electronic imaging capturing. Eliminates the need for an image plate altogether.

22. Amorphous Selenium detector technology for DR Direct Radiography

24. IMAGE CAPTURE CR • PSP – photostimulable phosphor plate • REPLACES FILM IN THE CASSETTE DR – NO CASSETTE – PHOTONS • CAPTURED DIRECTLY • ONTO A TRANSISTOR • SENT DIRECTLY TO A MONITOR

25. CR PSP in cassette Digital image Scanned & read- CR reader COMPUTER Image stored on computer Viewed on a Monitor Hard copy (film) can be made with laser printer FILM Film in cassette loaded in a darkroom Processed in a processor FILM Hard copy image – stores the image Viewboxes – view the images CR vs FS

26. CASSETTES with Intensifying Screens • The CASSETTE holds the film in a light tight container • It consist of front and back intensifying screens

27. CR BASICS • Eliminates the need for film as a recording, storage & viewing medium. • PSP Plate – receiver • Archive Manager – storage • Monitor - Viewing

28. General Overview CR • PSP cassette exposed by conventional X-ray equipment. • Latent image generated as a matrix of trapped electrons in the plate.

29. CR – PSP plate • photostimulable phosphor (PSP) plate • Captures photons • Stored in traps on plate (latent image) • PLATE scanned in CR READER

30. CR Phosphor Plates ABSORPTION EMISSION LASER STIMULATION ELECTRON TRAP ELECTRON TRAP X-RAY LIGHT

31. CR – PSP plate • Stimulated by a RED LIGHT • Energy is RELEASED in a form of BLUE light • LIGHT captured by PMT – • changed to a digiial signal

32. How CR works • Released light is captured by a PMT (photo multiplier tube) • This light is sent as a digital signal to the computer • The intensity (brightness) of the light – correlates to the density on the image

33. Densities of the IMAGE • The light is proportional to amount of light received • digital values are then equivalent (not exactly the same) to a value of optical density (OD) from a film, at that location of the image

35. ERASING PLATE • After image is recorded • Plate is erased with high intensity white light • and re-used

36. CR VS DR • CR -Indirect capture where the image is first captured on plate and stored = then converted to digital signal • DDR -Direct capture where the image is acquired immediately as a matrix of pixels – sent to a monitor

37. DIRECT RADIOGRAPHY • uses a transistor receiver (like bucky) • that captures and converts x-ray energy • directly into digital signal • seen immediately on monitor • then sent to PACS/ printer/ other workstations FOR VIEWING

38. CR imaging plate processed in a Digital Reader Signal sent to computer Viewed on a monitor DR transistor receiver (like bucky) directly into digital signal seen immediately on monitor – CR vs DR

40. CR 4000 x 4000 image only as good a monitor* 525 vs 1000 line more pixels = more memory needed to store CR 2 -5 lp/mm RAD 3-6 lp/mm DR ? IMAGE APPEARS SHARPER BECAUSE CONTRAST CAN BE ADJUSTED BY THE COMPUTER – (DIFFERENCES IN DENSITY) Image Resolution –(how sharply is the image seen)

41. ADVANTAGE OF CR/DR • Can optimize image quality • by manipulating digital data • to improve visualization of anatomy and pathology • AFTER EXPOSURE TO PATIENT

42. ADVANTAGE OF CR/DR • CHANGES MADE TO IMAGE • AFTER THE EXPOSURE • CAN ELIMINATE THE NEED TO REPEAT THE EXPOSURE

43. ADVANTAGE OF CR/DR vs FS • Rapid storage • retrieval of images NO LOST FILMS! • PAC (storage management) • Teleradiology - long distance transmission of image information • Economic advantage - at least in the long run?

44. CR/DR VS FILM/SCREEN • FILM these can not be modified once processed • If copied – lose quality • DR/CR – print from file – no loss of quality

45. “no fault” TECHNIQUES F/S: RT must choose technical factors (mAs & kvp) to optimally visualize anatomic detail CR: the selection of processing algorithms and anatomical regions controls how the acquired latent image is presented for display • HOW THE IMAGE LOOKS CAN BE ALTERED BY THE COMPUTER – EVEN WHEN “BAD” TECHNIQUES ARE SET

46. DR • Initial expense high • very low dose to pt – • image quality of 100s using a 400s technique • Therfore ¼ the dose needed to make the image

47. FILM/SCREEN films: bulky deteriorates over time requires large storage & expense environmental concerns CR & DR 8000 images stored on CD-R Jukebox CD storage no deterioration of images easy access Storage /Archiving

48. Transmission of Images • PACS - Picture Archiving & Communications System • DICOM - Digital Images & Communication in Medicine • TELERADIOGRAPHY -Remote Transmission of Images

49. Benefits of Computer (web)-based Viewing Systems • Hardcopy studies are no longer misplaced or lost- eliminates films • Multiple physicians may access same patient films • Patients do not have to wait in Radiology for films once study is completed

50. “Film-less” components • CR or DR • CD-ROM or similar output • Email capability • Digitizing capability or service