Table of Contents
ISRN Oncology
Volume 2014, Article ID 769698, 5 pages
http://dx.doi.org/10.1155/2014/769698
Research Article

Use of Flattening Filter-Free Photon Beams in Treating Medulloblastoma: A Dosimetric Evaluation

1CyberKnife Center, HealthCare Global Enterprises, No. 7, HCG Tower 2, Kalinga Rao Road, Sampangiram Nagar, Bangalore 560 027, India
2Department of Radiation Physics, Kidwai Memorial Institute of Oncology, Bangalore 560029, India

Received 30 September 2013; Accepted 4 November 2013; Published 21 January 2014

Academic Editors: R.-J. Bensadoun and L.-M. Sun

Copyright © 2014 Pichandi Anchineyan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Aim. To evaluate the dosimetric benefits of flattening filter-free (FFF) photon beams in intensity modulated radiation therapy (IMRT) and Rapid Arc (RA) over conventional CSI methods. Methods and Materials. Five patients treated with IMRT using static multileaf collimators (MLC) were randomly selected for this retrospective study. Dynamic MLC IMRT, RA, and conformal therapy (3DCRT) were iterated with the same CT data sets with and without flattening filter photons. Total dose prescribed was 28.80 Gy in 16 fractions. Dosimetric parameters such as , , , , , DHI, and CI for PTV and , , , , , and for OARs were extracted from DVHs. Beam on time (BOT) for various plans was also compared. Results. FFF RA therapy (6F_RA) resulted in highly homogeneous and conformal doses throughout the craniospinal axis. 3DCRT resulted in the highest (SD) , whereas flattening filter (FF) and FFF dynamic IMRT had a minimum . 6F_RA and 6F_DMLC resulted in lesser doses to thyroid, eyes, esophagus, liver, lungs, and kidneys. Conclusion. FFF IMRT and FFF RA for CSI have definite dosimetric advantages over 3DCRT technique in terms of target coverage and OAR sparing. Use of FFF in IMRT resulted in 50% reduction in BOT, thereby increasing the treatment efficiency.