뇌동정맥기형의 감마나이프 방사선 수술

Advanced Treatment Planning Method for Gamma Knife Radiosurgery of Cerebral Arteriovenous Malformations

Since March 1992, total 200 patients who visited our hospital as functional or organic lesions of central nervous system were treated by gamma knife stereotactic radiosurgery for 27 months. Thirty-nine patients of total cases was diagnosed as cerebral arteriouvenous malformation. The rate of magnification on X-ray film was reduced by cutting fixation adaptor from 1.6 to below 1.45 times. In order to treat the deep- and lateral- seated cereral arteriovenous malformation, we slightly modified the angiographic indicator, the commercial Leksell system, by cutting each inner sides about 5mm. We performed the more distinction of the scales by adapting 0.5mm or 1,, copper filter to angiographic indicator. The center point of indicator (X=100mm, Y=100mm, Z=100mm) si corrected by adjusting scales of X-, Y-, Z-axis to each inner 100 and outer 100point within 1-2mm by repeated exposure of X-ray on films in trial-and-errors. We have developed the 'GKANGID' programed as the Fortran-77 in Microvax-3100, which can save treatment planning time and perform accurate pretreatment planning using the theoretical target metrix center. The theoretical description of the simplified method is presented form the reduction of experimental and numerical errors in treatment planning of radiosurgery.