title: Bladder-rectum spacer balloon in high-dose-rate brachytherapy in cervix carcinoma.
abstract: OBJECTIVE
  To compare bladder and rectum doses with the use of a bladder-rectum spacer balloon (BRSB) versus standard gauze packing in the same patient receiving 2 high-dose-rate intracavitary brachytherapy fractions.
  
  
  METHODS
  This was a randomized study to compare the reduction in bladder and rectum doses with the use of a BRSB compared with standard gauze packing in patients with carcinoma of the cervix being treated with high-dose-rate intracavitary brachytherapy. The patients were randomized between 2 arms. In arm A, vaginal packing was done with standard gauze packing in the first application, and BRSB was used in the second application. Arm B was the reverse of arm A. The International Commission for Radiation Units and Measurement (ICRU) point doses and doses to 0.1-cm(3), 1-cm(3), 2-cm(3), 5-cm(3), and 10-cm(3) volumes of bladder and rectum were compared. The patients were also subjectively assessed for the ease of application and the time taken for application. Statistical analysis was done using the paired t test.
  
  
  RESULTS
  A total of 43 patients were enrolled; however, 3 patients had to be excluded because the BRSB could not be inserted owing to unfavorable local anatomy. Thus 40 patients (80 plans) were evaluated. The application was difficult in 3 patients with BRSB, and in 2 patients with BRSB the application time was prolonged. There was no significant difference in bladder doses to 0.1 cm(3), 1 cm(3), 2 cm(3), 5 cm(3), and 10 cm(3) and ICRU bladder point. Statistically significant dose reductions to 0.1-cm(3), 1-cm(3), and 2-cm(3) volumes for rectum were observed with the BRSB. No significant differences in 5-cm(3) and 10-cm(3) volumes and ICRU rectum point were observed.
  
  
  CONCLUSIONS
  A statistically significant dose reduction was observed for small high-dose volumes in rectum with the BRSB. The doses to bladder were comparable for BRSB and gauze packing. Transparent balloons of variable sizes are recommended for patients with a less spacious vaginal cavity.
authors.affiliation: Department of Radiotherapy and Oncology, Regional Cancer Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Bhavana
authors.initials: B
authors.lastname: Rai
authors.forename: Firuza D
authors.initials: FD
authors.lastname: Patel
authors.forename: Santam
authors.initials: S
authors.lastname: Chakraborty
authors.forename: Suresh C
authors.initials: SC
authors.lastname: Sharma
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kapoor
authors.forename: Abi Santhosh
authors.initials: AS
authors.lastname: Aprem
mesh_terms: D001918:Brachytherapy / Q000295:instrumentation / Q000379:methods*; D057785:Catheters; D004209:Disposable Equipment; D005260:Female; D006801:Humans; D007194:India; D007840:Latex; D058958:Organs at Risk / Q000528:radiation effects*; D010570:Pessaries; D011446:Prospective Studies; D011832:Radiation Injuries / Q000517:prevention & control*; D011879:Radiotherapy Dosage; D012007:Rectum / Q000033:anatomy & histology / Q000528:radiation effects*; D001743:Urinary Bladder / Q000033:anatomy & histology / Q000528:radiation effects*; D002583:Uterine Cervical Neoplasms / Q000532:radiotherapy*; D014621:Vagina / Q000033:anatomy & histology
chemical_list: D007840:Latex