الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
This study attempts to evaluate different methods of the Intensity Modulated Arc Therapy (IMRT) planning in comparison with practical radiation dosimetry for cancer patients by evaluating a number of plans with different techniques. We evaluated three dimensional conformal radiation therapy (3DCRT) plans (as forward planning) and IMRT plans (as inverse planning) to conclude the best accepted technique (that can reach 7400cGy safely from one phase only) with accepted Planning Target Volume (PTV) dose coverage and Organ at Risks (OARs) sparing. In-vivo practical dosimetry measures the dose to the target volume through indirect measurements at the end of the treatment planning chain. We evaluated all data used for comparison with practical measurements before applying these results for treatment of real cancer patients (prostate and head and neck). We evaluated different plans (3DCRT, IMRT, RapidArc) based on radiobiological planning in treating cancer, set dose constraints and satisfy the desired dose distributions both for PTV coverage and OAR’s sparing. For all selected prostate cases, 3DCRT and IMRT plans were verified and evaluated by Electronic Portal Imaging Device (EPID) practical radiation dosimetry system using the PDIP algorithm under the gamma criteria set to ΔD = 3% and Δd = 3mm. We used the Delta4 phantom detectors (2D plane and 3D plane) to check RapidArc plans under gamma criteria of (ΔD=3%, DTA=3mm and γ-index ≤1) while the threshold dose is 20%. The selected prostate treatment plan (7) with parameters of (five equally weighted fields with angles of (0o, 45o, 90o, 270o and 315o) and energy 15MV) is the recommended plan that can be acceptable and saves more time; as the limited use of both IMRT and RapidArc plans is proportional to the high cost of required equipment, operations and experienced team costs that were expensive on those patients more than 3DCRT technique. The selected and evaluated head and neck 3DCRT plan can be used (as forward IMRT plan) for each patient with coplanar beams arrangement techniques as accepted template plans for treatment of head and neck cases. RapidArc plans could be verified using Delta4 practical radiation dosimetry system, which gives excellent dosimetry results.