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Image Evaluation. Guidelines for Image Analysis Chapter 1. Facility’s Id Correct marker Required anatomy Accurate projection/position No unwanted distortion Cortical Outlines sharp Collimation Radiation Protection IR size & alignment Correct IR system Density & penetration
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Image Evaluation Guidelines for Image Analysis Chapter 1
Facility’s Id • Correct marker • Required anatomy • Accurate projection/position • No unwanted distortion • Cortical Outlines sharp • Collimation • Radiation Protection • IR size & alignment • Correct IR system • Density & penetration • Image contrast • No preventable artifacts • Properly ordered • Requisition & Post-procedure
Facility’s ID • Facility’s name • Patient’s name, age or birth date • Exam time and date • ID plate * outside collimated field * away from direction CR is angled * next to narrowest anatomical
Marking Images • Within collimated field? • Best position? • Accurate *Screen film *Digital * Is Required anatomy present on image?
Patient Obliquity & Extremity Flexion • Accurate position demonstrated • Imaginary line • Degree of extension
Shape Distortion • CR • Elongation • Foreshortening • Joint spaces • Poor positioning * magnified structure
Helpful Hints • Use a grid if part thickness is over 5 inches and over 70 kVp is used • Small to medium plaster cast • +5-7 kVp +50-60% mAs • Large plaster cast • +8-10 kVp + 100% mAs • Fiberglass cast • +3-4 kVp + 25-30% mAs
Detail Sharpness • Small focal spot • Unwanted motion • No magnification • Detail screen • Poor screen film contact • If CR is used; small possible IR
Collimation • All four sides • Within ½ inch of skinline • To specific anatomy on torso • All required anatomy visible
Radiation Protection • Present • Accurate for male and female • Tight collimation • Anatomical artifacts • Personnel protected • * IR positioned CW or LW properly
Body Habitus • CW or LW • Smallest IR, multiple positions • Aligned in same direction • Correct IR system
Density & Penetration • Optimal density • Overexposure & Underexposure • Changing penetration • Hypothetical conversation • Compensating filter or anode heel effect
Guidelines for Digital • Correct diagnostic specifier for anatomy • For non-routine correct specifier • Center structure • Do not overlap collimation edges • Collimate tightly
Image Contrast • Bony & soft tissue • Amount of scatter controlled
Ordered Procedure • Postprocedure • Repeat or reject analysis