الفهرس | Only 14 pages are availabe for public view |
Abstract In this thesis, dynamic multileaf collimator is implemented for treatment of prostate cancer with arcs of full rotation range to conform to the target and shield the rectum projections at the various rotation angles. The intended concave isodoses are given by forward planning dose calculation with two techniques. The dose homogeneity in the target volume is introduced by applying two lateral oblique wedged conformal fields with the full arcs with one of the two techniques, and by using a hard wedge opposed with two bilateral (180 degree) set of arcs with the second technique. The first is termed as “Modified Dynamic Arc Therapy” (M-DAT) and the second is termed as “Bilateral Wedged Dynamic Arc Therapy” (BW-DAT). M-DAT is applied for the treatment of the prostate plus seminal vesicles as well as for the prostate only, while BW-DAT is only applied for the treatment of the prostate only. M-DAT was compared with the previously published simplified intensity modulated arc therapy (SIMAT) technique for the treatment of the prostate plus seminal vesicles by differential doses. Both M-DAT and BW-DAT are compared with the inverse planning intensity modulated radiotherapy (IMRT) and the recent published dynamic arc therapy techniques; the “Dynamic arc therapy” (DAT) and “two-axis dynamic arc therapy” (2A-DAT). Each of M-DAT and BW-DAT is applied for treatment of 10 patients in supine positioning and 10 others in prone positioning to determine the proper patient positioning for optimum protection of the rectum |