Document Type: Original Paper
Department of Radiotherapy, Chirayu Medical College and Hospital, Bhopal-462030 (M.P), India
Department of Radiotherapy, Gandhi Medical College, Bhopal-462001(M.P.), India and Department of Physics, Rabindranath Tagore University (formerly known as AISECT University), Raisen- 464993 (M.P), India
Department of Radiotherapy, Chirayu Medical College & hospital,Bhopal-462030 (M.P), India.
Department of Physics, Rabindranath Tagore University (formerly known as AISECT University), Raisen- 464993 (M.P), India
Aim: In this study we have evaluated the dosimetric comparison between 6MV Flattened Filter (FF) and Flattening Filter Free (FFF) photon beam in intensity modulated radiation therapy (IMRT) technique for treatment of glioblastoma patients.
Materials & Methods: 10 patients of glioblastoma previously treated with 6MV FF photon beam by IMRT technique were selected for this study. Retrospectively, additional IMRT plans were created using 6MV FFF photon beam for each patient already planned and treated with 6MV FF photon beam keeping same dose prescription of 60 Gy in 30 fractions. The beam parameters (beam angle, number of beams) and planning objective in inverse optimization were kept same in both 6MV_FF_IMRT and 6MV_FFF_IMRT plans. IMRT plans with 6MV FF photon beam and FFF photon beam were evaluated from cumulative Dose Volume Histogram(c-DVH). Both types of plans were compared on the basis of Homogeneity Index (HI), Conformity Index (CI), Beam on Time (BOT), Monitor Unit (MU) and doses to organs at risk (OARs).
Results: D95% of PTV coverage was found significantly higher in 6MV_FF_IMRT plan in comparison to 6MV_FFF_IMRT Plan (p