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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology. RADIATION PROTECTION IN DIAGNOSTIC AND INTERVENTIONAL RADIOLOGY. Part 16.5: Optimization of protection in fluoroscopy Practical exercise. Overview.
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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology RADIATION PROTECTION INDIAGNOSTIC ANDINTERVENTIONAL RADIOLOGY Part 16.5: Optimization of protection in fluoroscopy Practical exercise
Overview • To become familiar with quality control tests in fluoroscopy • To measure the imaging geometry and sizing • Interpretation of results 16.5: Optimization of protection in fluoroscopy
IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology Part 16.5: Optimization of protection in fluoroscopy Image Distortion
Leeds Fluoroscopy Phantom Image distortion • Pincushion distortion results because the input phosphor is curved but the output phosphor is flat • This results in a warped image, which bends straight lines inwards • Pincushion distortion is reduced when magnification modes are used 16.5: Optimization of protection in fluoroscopy
Image distortion Pin-cushion S-distortion 16.5: Optimization of protection in fluoroscopy
Leeds Fluoroscopy PhantomImaging geometry and sizing • Incorporates: • a wire matrix of 20 mm square spacing with 10 mm minor indicators 16.5: Optimization of protection in fluoroscopy
Leeds Fluoroscopy PhantomImaging geometry and sizing • Interpretation of results • Measured field size > 0.85 nominal diameter of the intensifier • Integral distortion = (mean diagonal of large square - 1) n x mean diagonal of central square • less than 10 %. 16.5: Optimization of protection in fluoroscopy
Where to Get More Information Quality Control in Diagnostic Imaging, Gray JE, Winkler NT, Stears J, Frank ED. Available at no cost. http://www.diquad.com/QC%20Book.html 15.3: Optimization of protection in radiography