RADIATION PROTECTION IN DIAGNOSTIC AND INTERVENTIONAL RADIOLOGY

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RADIATION PROTECTION INDIAGNOSTIC
ANDINTERVENTIONAL RADIOLOGY
IAEA Training Material on Radiation Protection in
Diagnostic and Interventional Radiology

• Part 16.5 Optimization of protection in
  fluoroscopy
• Practical exercise

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Overview / Contents

• To become familiar with quality control test in
  fluoroscopy
• To measure the imaging geometry and sizing
• Interpretation of results

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Part 16.5 Optimization of protection in
fluoroscopy
IAEA Training Material on Radiation Protection in
Diagnostic and Interventional Radiology

• Image Distortion

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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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Image distortion
Pin-cushion
S-distortion
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Leeds Fluoroscopy Phantom Imaging geometry and
sizing

• Incorporates
• a wire matrix of 20 mm square spacing with 10 mm
  diametrical interpolations

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Leeds Fluoroscopy Phantom Imaging geometry and
sizing

• Interpretation of results
• Measured filed size gt 0.85 nominal diameter of
  the I.I.
• Integral distortion (mean diagonal of large
  square - 1)
  n x mean diagonal of central square
• less than 10 .