Exact Measurement of Gamma-Ray Doses in the Ureter

Abstract

WE have attempted to evolve a method for the accurate measurement of the radiation dose received by the ureter during radium therapy. Our radiation meter is a small rod-shaped piece of metaphosphate glass measuring 1 × 6 mm, which fits into a No. 6 ureteral catheter. In the course of a cystoscopy performed before the radiation therapy, one of us (O. W.) placed this measuring device in the tip of the ureteral catheter. A new hole was made in the catheter about 1.5 cm from its tip and the catheter as a whole inclusive of the glass was sterilized in formalin. The catheter was fixed to the thigh and the application of radium or cobalt was then carried out. Tho catheter or catheters were left in situ for about 30 min. The position of the catheters was controlled using the routine radiograms taken for the isodose curves. The pieces of glass have a wide measuring range (50 mr.–10,000 r.) and a notable correlation with energy.