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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology. RADIATION PROTECTION IN DIAGNOSTIC AND INTERVENTIONAL RADIOLOGY. Part 15.7: Optimization of protection in radiography Practical exercise - processor. Overview / Objectives.
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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology RADIATION PROTECTION INDIAGNOSTIC ANDINTERVENTIONAL RADIOLOGY Part 15.7: Optimization of protection in radiography Practical exercise - processor
Overview / Objectives • Subject matter : quality control of the processor • Step by step procedure to be followed to implement the considered QC test: • film storage, cassette and screen, sensitometry • Interpretation of results 15.7: Optimization of protection in radiography
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology Part 15.7: Optimization of protection in radiography Topic 1: Processor evaluation (film storage, cassette and screen, sensitometry)
What Minimum Equipment is Needed? • Thermometer • Sensitometer • Densitometer • Manufacturer’s cleaning solutions • Ultraviolet (“Black Light”) light 15.7: Optimization of protection in radiography
Film Processor QC • Most important QC features : • proper film storage • cassette and screen care • processor chemical care • sensitometry • artifacts • processor cleanliness 15.7: Optimization of protection in radiography
Film Processor QC 15.7: Optimization of protection in radiography
Film Processor QC - Film Storage • Film should be stored in cool, dry conditions < 26° C, 30-60% relative humidity • Film storage area should be adequately shielded from x-ray exposure • Too low humidity allows static discharge • Storage period must not be too long • Stack film boxes vertically to avoid pressure on films 15.7: Optimization of protection in radiography
Cassette and Screen Care • Clean screens periodically to avoid dust shadows • Use manufacturer’s recommended cleaning solutions • An ultraviolet (“Black Light”) light can show up dust 15.7: Optimization of protection in radiography
Processor Chemical Care • Chemicals (developer and fixer) degrade with time and use • Developer in particular will oxidize (go brown) and become depleted with use resulting in poor quality (reduced contrast and film speed) films • Fixer will change pH and lose emulsion hardener 15.7: Optimization of protection in radiography
Film Processor QC 15.7: Optimization of protection in radiography
Processor Chemical Care • Chemicals must be replenished (continual automatic replacement) • Use manufacturer’s recommendations • Check the developer temperature daily - processing is very sensitive to temperature Note: If the number of films processed per day is low, it will be necessary to use flood replenishment. See Flood replenishment: a new method of processor control. Frank ED, Gray JE, Wilken DA. Radiol Technol. 52:271-275, 1980 15.7: Optimization of protection in radiography
Sensitometry • Sensitometer and densitometer required • Essential to keep the process under control • To be performed daily • Main parameters investigated: • Base-plus-fog • mid-density • density difference (See reference to ACR Quality Control Manual, and Quality Control in Diagnostic Imaging, last slide) 15.7: Optimization of protection in radiography
Film Processor QC - Artifacts • Anything on the film which is not related to the x-ray image • Examples : • dust marks, static discharge • fixer stains (poor washing) • film storage problems • processor problems (roller marks, scratches) 15.7: Optimization of protection in radiography
Film Processor QC - Processor Cleanliness • All processors will eventually get dirty • Clean processor according to manufacturer’s instructions • Daily cleaning of entrance trays and cross-over racks is essential 15.7: Optimization of protection in radiography
Where to Get More Information • Part XIII.8 “Optimization of protection for Mammography” Practical exercise • Flood replenishment: a new method of processor control. Frank ED, Gray JE, Wilken DA. Radiol Technol. 52:271-275, 1980 • American College of Radiology Mammography Quality Control Manual, Reston VA, 1999. • Quality Control in Diagnostic Imaging, Gray JE, Winkler NT, Stears J, Frank ED. Available at no cost. http://www.diquad.com/QC%20Book.html 15.7: Optimization of protection in radiography