MEDRADSC 2F03 Lecture Notes - Lecture 7: Pubic Symphysis, Coccyx, Axial Tilt

• School: McMaster University
• Department: Medical Radiation Sciences
• Course: MEDRADSC 2F03
• Professor: Lumsden

Document Summary

Misreprese(cid:374)tatio(cid:374) of a(cid:374) o(cid:271)je(cid:272)t"s lo(cid:272)atio(cid:374) o(cid:374) i(cid:373)age relative to other o(cid:271)je(cid:272)ts: superimposition, different shape, larger than normal. Object at off the ir higher is projected further from the central ray than one closer to the ir, so larger oid appears to be more peripheral than actual. We can use this to our advantage: angle ray for coccyx to see more of symphysis pubis. Minimizing: orient objects so that the rays have minimal obliquity relative to ir, try centering everything around the central ray. Sometimes distortion works so that we see things better. Remove superimposition of two objects by applying location distortion. Map object onto larger area of ir by applying magnification. Prime factors (three factors that affect x-ray emission) Differential attenuation: differential absorption: as kvp increases, differential absorption increases (more white), high quality radiographs require the proper kvp so that the effective x-ray energy results in max differential absorption.