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.

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Transcript 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. 

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
IAEA
International Atomic Energy Agency
Overview
• To become familiar with quality control
tests in fluoroscopy
• To measure the imaging geometry and
sizing
• Interpretation of results
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16.5: Optimization of protection in fluoroscopy
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IAEA Training Material on Radiation Protection in Diagnostic and Interventional Radiology
Part 16.5: Optimization of protection in
fluoroscopy
Image Distortion
IAEA
International Atomic Energy Agency
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
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16.5: Optimization of protection in fluoroscopy
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Image distortion
Pin-cushion
IAEA
S-distortion
16.5: Optimization of protection in fluoroscopy
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Leeds Fluoroscopy Phantom
Imaging geometry and sizing
Incorporates:
• a wire matrix of 20
mm square spacing
with 10 mm minor
indicators
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Leeds Fluoroscopy Phantom
Imaging 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 %.
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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
IAEA
15.3: Optimization of protection in radiography
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