Irradiation dose distribution and safety of 90Sr/90Y prostatic hyperplasia applicator (urethra-type) in the treatment of BPH

Objective: To study the irradiation dose distribution and safety of 90Sr/90Y prostatic hyperplasia applicator in clinical application. Methods: Characteristics of dosimetry of 90Sr/90Y applicator were determined using nuclear detection techniques in body-phantom. The distribution of the surface dose rate had been measured using lithium fluoride (LiF) thermoluminescent dosimeter during the treatment of the patients. Results: The absorbed doses of β-ray were decreased with the increased distances. The decreased percentages of the absorbed doses at the measured distances of 1 mm, 5 mm and 13 mm to the center of applicator were respectively 57.40%, 99.21% and 99.98% in the body-phantom. No obvious difference was found in the results of surface dose rate of bremsstrahlung. The absorbed doses of doctors and patients were much lower than that of the nation limits. Conclusion: 90Sr/90Y applicator was safe and effective for the treatment of the patients with prostatic hyperplasia. (authors)