Abstract
The difference between conventional radiotherapy and conformal radiotherapy lies in the use of planning CT to define tumour volume and design treatment portals wherein treatment positions are checked by CT scans, target volumes and OARs defined and beams positioned. After planning CT is done with patient immobilized in treatment position, the treatment tumour volumes and normal organs are drawn or contoured on the CT images, and the radiation portals are designed to conform to the tumour volumes. Thus, conformal therapy requires more complex shaping of the dose distribution than does conventional radiotherapy since shaping of fields and the selection of beam directions are based on 3D reconstruction of the CT images of the patient. These images projected in a beam’s eye view (BEV) format permit selection of beam directions with better avoidance of normal tissues. After this computer-aided algorithms help in dose calculation and meeting plan objectives.
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Mukherji, A. (2018). Conformal Radiotherapy: Simulation and Contouring. In: Basics of Planning and Management of Patients during Radiation Therapy. Springer, Singapore. https://doi.org/10.1007/978-981-10-6659-7_10
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