Dosimetric Analysis of Physical and Enhanced Dynamic Wedge and Its Implication in 3D-Conformal Radiotherapy Planning | Insight Medical Publishing

Background: Across the history of radiotherapy, wedges are generally used to modify the shape of isodose lines to achieve desired clinical dose coverage to the target and to reduce the hot spot as well. Aim: The main aim of this study was to analyse and compare the dosimetric properties of Varian’s physical and enhanced dynamic wedges, and their dosimetric impact on radiotherapy plan (3D-Conformal). Materials and Methods: All plans were generated and evaluated in Varian’s eclipse planning system. For comparing the isodose line alteration, the plans were prepared in water phantom with field of size 10 cmx 10 cm. Wedges of angle 15°, 30°, 45° and 60° were used for generating isodose lines in the current study. All wedge factors were measured in water phantom using FC65 farmer type chamber. Discussion: In the current study, the dosimetric characteristics of EDW and PW were analyzed and compared. For analyzing the impact of EDW and PW, 22 patients were taken into consideration, and 50 Gy dose was prescribed to PTV in 25 fractions. Conclusion: The analysis of EDW and PW shows slightly different dosimetric features. EDW gives better target’s coverage, less hyper dose and comparatively less MUs as compare to PW. Hence the use EDW in 3D-conformal radiotherapy plan is a prudent practice.