The Study of Tissue Dose Perturbation by Air Cavity with 6MV Photon Beam.
- Author:
Byung Chul SHIN
1
;
Myung Jin YOO
;
Chang Woo MOON
;
Tae Sig JEUNG
;
Ha Yong YUM
Author Information
1. Department of Therapeutic Radiology, Medical College, Kosin University, Pusan, Korea.
- Publication Type:Original Article
- Keywords:
Dose perturbation;
Air/tissue interface;
Larynx
- MeSH:
Larynx
- From:Journal of the Korean Society for Therapeutic Radiology
1995;13(4):397-402
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To determine the perturbation effect in the tissue downstream from surface layers of lesions located in the air/tumor-tissue interface of larynx using 6MV photon beam. MATERIALS AND METHODS: Thermoluminescent dosimeters(TLDs). Were embedded at 3 measurement locations in slab no.7 of a humanoid phantom and exposed to forward and backward direction using various field sizes(4X4cm2 - 15X15 cm2). RESULTS: At the air/tissue interface, forward dose perturbation factor(FDPF) is about 1.085 with 4X4 cm2, 1.05 with 7X7 cm2, 1.048 with 10X10cm2, and 1.041 with 15X15cm2. Backscatter dose perturbation factor(BDPF) is about 0.99 with 4X4cm2, 0.981 with 7X7cm2, 0.956 with 10X10cm2 and 0.97 with 15X15cm2 . CONCLUSION: FDPF is greater as field size is smaller. And FDPF is smaller as the distance is further from the air/tissue interface.
