Thesis (Ph.D.) - Cairo University - Faculty of Science - Department of Biophysics

Purpose:The main aim of this work is to compare the conformity index and the peripheral doses absorbed during stereotactic treatment of a brain lesion delivered using three stereotactic techniques; Arcs, noncoplanar fixed conformal fields(3DCRT) and intensity modulation(IMRT).Materials and Methods: Ten patients with different tumor sizes, shapes and localisations were selected for this study. Treatment plans were generated using three different techniques: Arcs, noncoplanar fixed fields and intensity modulation techniques. Treatment plans (Arcs, IMRT, 3DCRT) were created for the pediatric anthropomorphic phantom for different target sizes To measure and calculate the Peripheral Doses(PDs).Results: The IMRT technique shows the highest dose conformity, Arcs technique is the next homogeneity followed by 3DCRT.The results show that Arcs technique has the lowest volume of the body that received 2 Gy, IMRT is the next followed by 3DCRT and IMRT technique has the lowest volume of the body that received 5 Gy, Arcs technique is the next followed by 3DCRT. IMRT plan delivery time almost has two folded more than the two others techniques, and the arc the technique has the lowest estimated time compared to both IMRT and Conformal techniques. the IMRT technique has the highest values of PDs at distanc close to the PTV the next is Arcs technique followed by 3DCRT technique which has the lowest values

Issued also as CD