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.
Download ReportTranscript 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.
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 IAEA International Atomic Energy Agency 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 IAEA 15.7: Optimization of protection in radiography 2 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) IAEA International Atomic Energy Agency What Minimum Equipment is Needed? • • • • • Thermometer Sensitometer Densitometer Manufacturer’s cleaning solutions Ultraviolet (“Black Light”) light IAEA 15.7: Optimization of protection in radiography 4 Film Processor QC • Most important QC features : • • • • • • proper film storage cassette and screen care processor chemical care sensitometry artifacts processor cleanliness IAEA 15.7: Optimization of protection in radiography 5 Film Processor QC IAEA 15.7: Optimization of protection in radiography 6 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 IAEA 15.7: Optimization of protection in radiography 7 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 IAEA 15.7: Optimization of protection in radiography 8 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 IAEA 15.7: Optimization of protection in radiography 9 Film Processor QC IAEA 15.7: Optimization of protection in radiography 10 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 IAEA 15.7: Optimization of protection in radiography 11 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) IAEA 15.7: Optimization of protection in radiography 12 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) IAEA 15.7: Optimization of protection in radiography 13 Film Processor QC - Processor Cleanliness • All processors will eventually get dirty • Clean processor according to manufacturer’s instructions • Daily cleaning of entrance trays and crossover racks is essential IAEA 15.7: Optimization of protection in radiography 14 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. 52:271275, 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 IAEA 15.7: Optimization of protection in radiography 15