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CHAPTER 39. PATIENT RADIATION DOSE MANAGEMENT. MINIMIZING EXPOSURESTO THE PATIENT. X-RAY EXPOSURES ARE INCREASING BY 18% EACH YEAR! NATURAL SOURCES ARE 3 mSv but x-ray is now at 3.2mSv due to???? Angiointerventional are reporting acute effects to ???. Patient dose estimation. ESE
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CHAPTER 39 PATIENT RADIATION DOSE MANAGEMENT
MINIMIZING EXPOSURESTO THE PATIENT • X-RAY EXPOSURES ARE INCREASING BY 18% EACH YEAR! • NATURAL SOURCES ARE 3 mSv but x-ray is now at 3.2mSv due to???? • Angiointerventional are reporting acute effects to ???
Patient dose estimation • ESE • See table 39-1 • How are they measured? • How accurate are the measurements • Which nomogram is more accurate? • Bone marrow –how is this measured? • Table 39.2 • Gonadal dose • GSD- • Suspected genetic effects of radiation • Epidemiologic study of averaging those who have been irradiated and those who have not
Mammography • ESE: 800 mR/view • Dose falls off rapidly after penetrating the breast so that by midline of breast, the dose is 100 mR • Any response is due to glandular dose which 15% of the ESE • Glandular dose should not exceed 100 mrad per view for contact and 300 mrad/view with grid
CT • Skin dose – high • 10% of all studies are CT -= 70% of patient effective dose • Collimation is fine • No scatter • Couch movement must be precise • What are the typical CT dose ranges for head and body. • Why do multislice images reduce patient dose? • Why is shielding not advantageous?
Let’s reduce radiation? How? • Examinations- let’s discuss • Repeats…look at yellow box • What else?
Pregnancy • Time dependence • Congenital abnormalities • Major organogenesis • Dose Dependence -percentages? • Patient info