title: Dosimetric comparison between intensity-modulated radiotherapy and RapidArc with single arc and dual arc for malignant glioma involving the parietal lobe.
abstract: The aim of the present study was to evaluate the difference in treatment plan quality, monitor units (MUs) per fraction and dosimetric parameters between IMRT (intensity-modulated radiotherapy) and RapidArc with single arc (RA1) and dual arc (RA2) for malignant glioma involving the parietal lobe. Treatment plans for IMRT and RA1 and RA2 were prepared for 10 patients with malignant gliomas involving the parietal lobe. The Wilcoxon matched-pair signed-rank test was used to compare the plan quality, monitor units and dosimetric parameters between IMRT and RA1 and RA2 through dose-volume histograms. Dnear-max (D2%) to the left lens, right lens and left optical nerve in RA1 were less compared with those in IMRT; D2% to the right lens and right optic nerve in RA2 were less compared with those in IMRT. D2% to the optic chiasma in RA2 was small compared with that in RA1. The median dose (D50%) to the right lens and right optic nerve in RA1 and RA2 was less compared with the identical parameters in IMRT, and D50% to the brain stem in RA2 was less compared with that in RA1. The volume receiving at least 45 Gy (V45) or V50 in normal brain tissue (whole brain minus the planning target volume 2; B-P) in RA1 was less compared with that in IMRT. V30, V35, V40, V45, or V50 in B-P in RA2 was less compared with that in IMRT. The MUs per fraction in RA1 and RA2 were significantly less compared with those in IMRT. All differences with a P-value<0.05 were considered to be significantly different. In conclusion, RA1 and RA2 markedly reduced the MUs per fraction, and spared partial organs at risk and B-P compared with IMRT.
authors.affiliation: Department of Radiation Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Yuan
authors.affiliation: Department of Radiation Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Mingjun
authors.initials: M
authors.lastname: Lei
authors.affiliation: Department of Radiation Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Department of Radiation Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Fu
authors.affiliation: The Institute of Skull Base Surgery and Neuro-Oncology at Hunan, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Lei
authors.initials: L
authors.lastname: Huo
authors.affiliation: Department of Radiation Oncology, Xiangya Hospital, Central South University, Changsha, Hunan 410008, P.R. China.
authors.forename: Jidong
authors.initials: J
authors.lastname: Hong
keywords: dosimetry; intensity-modulated arc radiotherapy; intensity-modulated radiotherapy; malignant glioma