The Role of Air-Vacuum Cushion Device in Patients with Rectal Cancer in Radiation Therapy.
- Author:
Ki Hwan KIM
1
;
Moon June CHO
;
No Hyun KANG
;
Dong Wuk KIM
;
Jun Sang KIM
;
Ji Young JANG
;
Jae Sung KIM
Author Information
1. Department of Therapeutic Radiology, Chungnam National University Hospital, Taejon, Korea.
- Publication Type:Original Article
- Keywords:
Immobilization;
Radiation therapy;
Rectal neoplasms
- MeSH:
Axis, Cervical Vertebra;
Chungcheongnam-do;
Control Groups;
Humans;
Immobilization;
Pelvic Bones;
Prone Position;
Rectal Neoplasms*;
Vacuum
- From:The Journal of the Korean Society for Therapeutic Radiology and Oncology
2001;19(3):287-292
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: We analyzed setup errors induced by using air-vacuum cushion as immobilization device in patients with rectal cancer. MATERIALS AND METHODS: We had treated the twenty patients with rectal cancer by 6 MV, 10 MVx-ray from Aug. 1998 to Aug. 1999 at Chungnam National University Hospital. All patients were treated at prone position. They were separated to two groups, control group, 10 patients using styrofoam, and test group, 10 patients using styrofoam and air-vacuum cushion. We measured errors of posterior field forx, y axis and lateral field for z, y axis with simulation film and EPID image using a matching technique. RESULTS: In control group, the mean displacement values of pelvic bone landmark forx axis and y axis were 0.02 mm. 0.78 mm, respectively and the standard deviations of systematic error were 2.13 mm, 2.40 mm, respectively and the standard deviation of random error were 1.46 mm. 1.51 mm, respectively. In test group, the mean displacement values ofx axis and y axis were -0.33 mm. 0.81 mm, respectively and the standard deviations of systematic error were 1.71 mm, 3.08 mm, respectively and the standard deviations of random errors were 1.40 mm. 1.88 mm, respectively. The mean displacement values of z axis and y axis were 2.98 mm. 0.74 mm, respectively and the standard deviations of systematic error were 4.75 mm, 2.65 mm, respectively and standard deviations of random error were 2.69 mm. 1.86 mm, respectively. The statistical difference of field size by using air vacuum cushion between two groups in posterior direction and lateral direction was not shown. CONCLUSION: We think that use of air-vacuum cushion may not be an advantage for improving setup accuracy in rectal cancer patients.
