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Background: Intensity Modulated Radiation Therapy (IMRT) is currently employed as a major arm of treatment in multiforme glioblastoma (GBM). The present study aimed to compare 3D-CRT with IMRT to assess tumor volume coverage and OAR sparing for the treatment of malignant gliomas. Materials and methods: We assessed 22 anonymized patients datasets with High Grade Glioblastoma who had undergone post-operative Intensity Modulated Radiotherapy (IMRT) and 3D Conformal Radiotherapy (3D-CRT), This study will compare and contrast treatment plans Rapidarc and 3D-CRT to determine which technology improves significantly dosimetric parameters. Results: Plans will be assessed by reviewing the coverage of the PTV using mean, maximum and minimum doses while the OAR doses will be compared using the maximal doses for each, as set out in the QUANTEC dose limits. Conclusion: The use of IMRT seems a superior technique as compared to 3D-CRT for the treatment of malignant gliomas having the potential to increase the dose to the PTV while sparing OARs optimally.

Purpose :The cardiac toxicities are especially important in left-sided breast cancer radiotherapy(RT) compared to the right-sidedcancers.Our study aims to perform a dosimetric analysis to evaluate the effect of RT on coronary arteries and heart in breast-conserving surgery. Methods : Through a dosimetric studywe randomly selected a total of 36 patients with early stage right and left-sided breast carcinomas (T1/T2 +N0) .All patients underwent breast-conserving surgery .Whole Breast Adjuvant Radiotherapy was delivered with tumor beds boost using 3D conformal radiotherapy (3D-CRT) and computed tomography based planning .The doses for coronary arteries and heart were recorded and median values compared between groups. Results :The highest mean of radiation dose in patients with left-sided breast cancer was to LAD 2402.48 ± 838.39 cGy, while the highest mean dose in right-sided breast cancer patientswas to RV 130.18 ± 24.92. The highest maximumdose of radiotherapy was applied to heart at left-sided breast cancer patients as well as at right-sides prients. Themean V5 of the LV was 18.68% (6.89–31.69), mean V25 of the LV was 5.22% (0.45–16.54), mean V5 in bilateral ventricleswas 23.73% (2.56–26.89), and mean V25 in bilateral ventricles 6.78% (0.63–13.63).

An evaluation of the lateral spread that the proton beams undergo during their interactions with a water phantom has been performed. We calculated and evaluated the dose distribution spatially deposed of protons acceleration up to energies between 70 and 215 MeV using a voxelized water phantom as a 3D detector. A 0.1 mm3 size precision voxel was used to detect and calculate the deposed energy and dose in any area of the water phantom using the GEANT4 platform based on the Monte-Carlo Method simulation. We find that, regardless of the initial proton energy, the lateral spread follows a parabolic pattern as a function of depth, and the ratio of the radius at the Bragg peak to the depth of the Bragg peak is around 2.8%. A good agreement has been found compared to other analytical models, simulation methods, and especially to experimental data.