Program Information
A Statistical Approach to Manage Quality for Pre-Treatment Verification in IMRT/VMAT
K Jassal1*, B Sarkar2 , B Mohanti3 , S Roy4 , T Ganesh5 , A Munshi6 , A Chougule7 , K Sachdev8 , (1) Fortis Memorial Research Institute, Gurgaon, Haryana, (2) AMRI Cancer Centre and GLA university, Mathura, Kolkata, West bengal, (3) FMRI, Gurgaon, Haryana, (4) FMRI, Gurgaon, Haryana, (5) FMRI, Gurgaon, Haryana, (6) Fortis Memorial Research Institute, Gurgon, haryana, (7) SMS Medical College and Hospital, Jaipur, Rajasthan, (8) Malaviya National Institute of Technology, Jaipur, Rajasthan
Presentations
SU-E-T-77 (Sunday, July 12, 2015) 3:00 PM - 6:00 PM Room: Exhibit Hall
Objective: The study presents the application of a simple concept of statistical process control (SPC) for pre-treatment quality assurance procedure analysis for planar dose measurements performed using 2D-array and a-Si electronic portal imaging device (a-Si EPID).
Method: A total of 195 patients of four different anatomical sites: brain (n1=45), head & neck (n2=45), thorax (n3=50) and pelvis (n4=55) were selected for the study. Pre-treatment quality assurance for the clinically acceptable IMRT/VMAT plans was measured with 2D array and a-Si EPID of the accelerator. After the γ-analysis, control charts and the quality index Cpm was evaluated for each cohort.
Results: Mean and σ of γ ( 3%/3 mm) were EPID γ %≤1= 99.9% ± 1.15% and array γ %<1 = 99.6% ± 1.06%. Among all plans γ max was consistently lower than for 2D array as compared to a-Si EPID. Fig.1 presents the X-bar control charts for every cohort. Cpm values for a-Si EPID were found to be higher than array, detailed results are presented in table 1.
Conclusion: Present study demonstrates the significance of control charts used for quality management purposes in newer radiotherapy clinics. Also, provides a pictorial overview of the clinic performance for the advanced radiotherapy techniques.Higher Cpm values for EPID indicate its higher efficiency than array based measurements.
Contact Email: