Dose Reduction Study in Vaginal Balloon Packing Filled With Contrast for HDR Brachytherapy Treatment;HDR; Uterine cervix cancer; Vaginal balloon packing; Contrast; Monte Carlo
- Radiation Oncology, Moffitt Cancer Center, Tampa, FL (United States)
Purpose: Vaginal balloon packing is a means to displace organs at risk during high dose rate brachytherapy of the uterine cervix. We tested the hypothesis that contrast-filled vaginal balloon packing reduces radiation dose to organs at risk, such as the bladder and rectum, in comparison to water- or air-filled balloons. Methods and Materials: In a phantom study, semispherical vaginal packing balloons were filled with air, saline solution, and contrast agents. A high dose rate iridium-192 source was placed on the anterior surface of the balloon, and the diode detector was placed on the posterior surface. Dose ratios were taken with each material in the balloon. Monte Carlo (MC) simulations, by use of the MC computer program DOSXYZnrc, were performed to study dose reduction vs. balloon size and contrast material, including commercially available iodine- and gadolinium-based contrast agents. Results: Measured dose ratios on the phantom with the balloon radius of 3.4 cm were 0.922 {+-} 0.002 for contrast/saline solution and 0.808 {+-} 0.001 for contrast/air. The corresponding ratios by MC simulations were 0.895 {+-} 0.010 and 0.781 {+-} 0.010. The iodine concentration in the contrast was 23.3% by weight. The dose reduction of contrast-filled balloon ranges from 6% to 15% compared with water-filled balloon and 11% to 26% compared with air-filled balloon, with a balloon size range between 1.4 and 3.8 cm, and iodine concentration in contrast of 24.9%. The dose reduction was proportional to the contrast agent concentration. The gadolinium-based contrast agents showed less dose reduction because of much lower concentrations in their solutions. Conclusions: The dose to the posterior wall of the bladder and the anterior wall of the rectum can be reduced if the vaginal balloon is filled with contrast agent in comparison to vaginal balloons filled with saline solution or air.
- OSTI ID:
- 21587621
- Journal Information:
- International Journal of Radiation Oncology, Biology and Physics, Vol. 80, Issue 4; Other Information: DOI: 10.1016/j.ijrobp.2010.08.033; PII: S0360-3016(10)03113-5; Copyright (c) 2011 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
- Country of Publication:
- United States
- Language:
- English
Similar Records
SU-G-TeP2-10: Feasibility of Newly Designed Applicator for High Dose Rate Brachytherapy Treatment of Patients with Vaginal Vault Recurrence
Bladder–Rectum Spacer Balloon in High-Dose-Rate Brachytherapy in Cervix Carcinoma
Related Subjects
BALLOONS
BLADDER
BRACHYTHERAPY
CONTRAST MEDIA
DOSE RATES
FEMALE GENITALS
GADOLINIUM
HAZARDS
IODINE
IRIDIUM 192
MONTE CARLO METHOD
NEOPLASMS
RADIATION DOSES
RECTUM
SIMULATION
AIRCRAFT
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
CALCULATION METHODS
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISEASES
DOSES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
GASTROINTESTINAL TRACT
HALOGENS
HEAVY NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
INTESTINES
IRIDIUM ISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LARGE INTESTINE
MEDICINE
METALS
MINUTES LIVING RADIOISOTOPES
NONMETALS
NUCLEAR MEDICINE
NUCLEI
ODD-ODD NUCLEI
ORGANS
RADIOISOTOPES
RADIOLOGY
RADIOTHERAPY
RARE EARTHS
THERAPY
URINARY TRACT
YEARS LIVING RADIOISOTOPES