title: Different effects of bladder distention on point A-based and 3D-conformal intracavitary brachytherapy planning for cervical cancer.
abstract: This study sought to evaluate the differential effects of bladder distention on point A-based (AICBT) and three-dimensional conformal intracavitary brachytherapy (3D-ICBT) planning for cervical cancer. Two sets of CT scans were obtained for ten patients to evaluate the effect of bladder distention. After the first CT scan, with an empty bladder, a second set of CT scans was obtained with the bladder filled. The clinical target volume (CTV), bladder, rectum, and small bowel were delineated on each image set. The AICBT and 3D-ICBT plans were generated, and we compared the different planning techniques with respect to the dose characteristics of CTV and organs at risk. As a result of bladder distention, the mean dose (D50) was decreased significantly and geometrical variations were observed in the bladder and small bowel, with acceptable minor changes in the CTV and rectum. The average D2 cm(3)and D1 cm(3)showed a significant change in the bladder and small bowel with AICBT; however, no change was detected with the 3D-ICBT planning. No significant dose change in the CTV or rectum was observed with either the AICBT or the 3D-ICBT plan. The effect of bladder distention on dosimetrical change in 3D-ICBT planning appears to be minimal, in comparison with AICBT planning.
authors.affiliation: Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Irwon-dong 50, Gangnam-gu, Seoul, 135-710, South Korea.
authors.forename: Sang Gyu
authors.initials: SG
authors.lastname: Ju
authors.forename: Seung Jae
authors.initials: SJ
authors.lastname: Huh
authors.forename: Jung Suk
authors.initials: JS
authors.lastname: Shin
authors.forename: Won
authors.initials: W
authors.lastname: Park
authors.forename: Heerim
authors.initials: H
authors.lastname: Nam
authors.forename: Sunhyun
authors.initials: S
authors.lastname: Bae
authors.forename: Dongryul
authors.initials: D
authors.lastname: Oh
authors.forename: Chae-Seon
authors.initials: CS
authors.lastname: Hong
authors.forename: Jin Sung
authors.initials: JS
authors.lastname: Kim
authors.forename: Youngyih
authors.initials: Y
authors.lastname: Han
authors.forename: Doo Ho
authors.initials: DH
authors.lastname: Choi
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D055119:Elastic Modulus; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008875:Middle Aged; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods; D061089:Radiotherapy, Image-Guided / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods; D016896:Treatment Outcome; D001743:Urinary Bladder / Q000503:physiopathology* / Q000528:radiation effects; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000532:radiotherapy*