Contamination Measurements of Patient’s Lead-Insulated Rooms After I-131 and LU-177 PSMA Treatment via Sweeping Test

Abstract

I-131 and Lu-177 PSMA radionuclides have been widely used in the field of nuclear medicine to treat thyroid cancer for many years. In this treatment, the patients whose dose rate measurements are less than 3 mR/h are generally discharged from the lead-insulated rooms where they are hospitalized. The aim of our study is to evaluate the contamination measurements of these rooms after I-131 and LU-177 PSMA treatment and to ensure radiation safety. A sweeping test was carried out by using Whatman papers (10x10 cm2 in size) to take samples from designated areas of these rooms in which three patients were treated with Lu-177 PSMA and four patients were treated with the I-131 radionuclide. Whatman papers are placed inside different tubes to prevent external contamination. Afterward, counting procedure was taken to the tubes for one minute by using the gamma counter which has different calibration factors both for Lu-177 and I-131 radionuclides. For the background extraction, one-minute counting test was applied to one of the Whatman papers that were not used for sweeping and background value was then obtained. It was statistically understood that the highest contamination rate was observed on the surface of toilet potteries in each room. As a result, ventilation of the room, meticulous cleaning of contaminated areas and the sweeping test must be implemented in each room where the patients are treated with radionuclides before the treatment of other patients.