摘要
37例经伽玛刀18mm准直器治疗的脑膜瘤和听神经瘤,计算其20％等剂量曲线内的体积,然后在周边剂量和等中心点数不变的情况下,重新用14mm准直器进行剂量计划。显示:中心剂量明显高于原中心剂量(P<0.001);与原20％等剂量曲线剂量相等的新等剂量曲线所包含的体积比原体积明显减少(P<0.001)。说明使用小准直器治疗大病灶时,中心剂量提高,但周围脑组织受照射的范围比大准直器减少。
The effects of 18mm and 14mm diameter collimators on central dose of targets and ex-tratarget volume during dose planning of large lesions were compared. The data taken from thirty-seven patients with large intracranial lesions treated with 18mm collirnators during dose planning and gamma knife treatment, were transferred back to Gamma Plan system, and the volume of 20% isodose curve was calculated. Then, we did dose planning again with 14mm collimator instead of 18mm collimator without the change of the number of isocenters and marginal dose. The results showed that the central dose of new treatment protocols was significantly higher than that of the old ones (P<0. 001); and the volume of 20% isodose line of the original dose planning was significantly larger than that of the isodose line (with the same dose as the original 20% isodose line) in the new dose planning. The study demonstrates that the volume of extratarget with 14mm collimator in dose planning of large lesions is significantly lower than that with 18mm collimators, although the central dose is higher.
出处
《临床神经科学》
1996年第2期93-95,共3页
Chinese Journal of Clinical Neurosciences
