Dosimetric Evaluation of the Treatment Plan on Indigenous Heterogeneous Phantoms using Analytical Anisotropic Algorithm and Acuros-XB Algorithm for Different Photon Energies
نویسندگان
1 PhD, Department of Applied Science & Humanities, Dr. A.P.J Abdul Kalam Technical University, Lucknow, India
2 PhD, Medical Physics Division & Department of Radiation Oncology, Rajiv Gandhi Cancer Institute and Research Center, New Delhi, India
3 PhD, Department of Physics Bareilly College Bareilly, Uttar Pradesh, India
4 MSc, Apollomedics Hospital, Lucknow, India
5 PhD Candidate, Department of Physics, M.J.P. Rohilkhand University, Bareilly Uttar Pradesh, India
6 PhD, Government Cancer Hospital, Mahatma Gandhi Memorial Medical College, Indore-452001, India
7 PhD, Department of Radiation Oncology, Ram Manohar Lohia Medical sciences Lucknow, India
doi
10.31661/jbpe.v0i0.2012-1246چکیده
Background: Modern radiotherapy techniques are using advanced algorithms; however, phantoms used for quality assurance have homogeneous density; accordingly, the development of heterogeneous phantom mimicking human body sites is imperative to examine variation between planned and delivered doses. Objective: This study aimed to analyze the accuracy of planned dose by different algorithms using indigenously developed heterogeneous thoracic phantom (HT). Material and Methods: In this experimental study, computed tomography (CT) of HT was done, and the density of different parts was measured. The plan was generated on CT images of HCP with 6 and 15 Megavoltage (MV) photon beams using different treatment techniques, including three-dimensional conformal radiotherapy (3D-CRT), intensity-modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT). Plans were delivered by the linear accelerator, and the dose was measured using the ion chamber (IC) placed in HT; planned and measured doses were compared. Results: Density patterns for different parts of the fabricated phantom, including rib, spine, scapula, lung, chest wall, and heart were 1.849, 1.976, 1.983, 0.173, 0.855, and 0.833 g/cc, respectively. Variation between planned and IC estimated doses with the tolerance (±5%) for all photon energies using different techniques. Acuros-XB (AXB) showed a slightly higher variation between computed and IC estimated doses using HCP compared to the analytical anisotropic algorithm (AAA). Conclusion: The indigenous heterogeneous phantom can accurately simulate the dosimetric scenario for different algorithms (AXB or AAA) and be also utilized for routine patient-specific QA.
