1. CHAPTER 39 PATIENT RADIATION DOSE MANAGEMENT

2. 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 ???

3. 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

4. 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

5. 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?

6. Let’s reduce radiation? How? • Examinations- let’s discuss • Repeats…look at yellow box • What else?

7. Pregnancy • Time dependence • Congenital abnormalities • Major organogenesis • Dose Dependence -percentages? • Patient info