Clinical evaluation of an interstitial remote afterloading device for multichannel intracavitary irradiation.

Abstract

The purpose of this report is to describe the clinical implementation and evaluation of an interstitial remote afterloading device for multichannel intracavitary brachytherapy. Two 15-channel low dose rate devices were adapted for use with Fletcher-Suit tandem and ovoids and Simon-Heyman capsules. The technical records for 103 intracavitary brachytherapy procedures performed from February 1989 through February 1991 were reviewed. Isodose distributions from fixed source trains for Microselectron low dose rate gynecologic applicators closely approximate standard manual afterloading sources and applicators. Device malfunctions occurred in 51% (53 out of 103) of the procedures. Malfunctions by applicator type were 70% (51 out of 73) for tandem, ovoids, and capsules, 12% (2 out of 17) for tandem and ovoids, and none (0 out of 13) for ovoids only. The most common malfunction occurred during source transfer. Total implant time was prolonged 0 to 4% by malfunction and 10% by patient care interruptions, depending on applicator type. The adaptation of the Microselectron device for multichannel gynecologic intracavitary brachytherapy results in similar dose distributions as standard manual after loading sources and a decreased radiation exposure to nursing personnel. The system has a high rate of malfunctions but a low overall prolongation of implant time due to malfunction.