STUDIES ON THE QUANTITY OF RADIATION REACHING THE GONADAL AREAS DURING DERMATOLOGIC X-RAY THERAPY .3. SHIELDING TECHNICS AND OTHER PRECAUTIONS FOR REDUCING THE GONAD DOSE

[摘要] Measurements were made of the amount of ionizing radiation reaching the gonadal areas of a pressed wood phantom (comparable to the gonad dose in patients receiving routine dermatologic X-ray therapy under various commonly encountered conditions). The possible sources of the ionizing radiation comprising the gonad dose are discussed. A lead-rubber sheet 0.06 inches thick (1/16 inch) wrapped around the lower 2/3 of the phantom lying horizontally on the X-ray table reduces the gonad dose by approximately 50%. Reduction of the size of the irradiated field, in combination with direct shielding of the gonadal area, is the most effective method of reducing the gonad dose in the seated phantom. The dose can be reduced 97%. A lead cone devised to extend from the X-ray tube aperture reduces the gonad dose in the seated phantom by 50%.