1990年4月～1995年12月共有82例听神经瘤患者在Mayo医院使用立体定向放射外科方法治疗。1993年11月前和后分别使用“标准剂量方案”和“减小的剂量方案”,目的在于确定使用减小的剂量是否既能保持肿瘤控制又能减少治疗后颅神经并发症。患者年龄≥18岁,听神经瘤由CT或MRI确定,肿瘤最大直径≤4cm。另外,患者为:①不宜或拒绝手术,且适宜用放射外科治疗。②肿瘤侵犯的是有功能的耳。③肿瘤存在于两侧。④或为以前曾手术过,目前有肿瘤残存或复发。 共42例患者使用“标准剂量方案”,肿瘤边缘剂 From April 1990 to December 1995, 82 patients with acoustic neuroma were treated with stereotactic radiosurgery in Mayo Hospital. The “Standard Dosage Protocol” and the “Reduced Dosage Protocol” were used before and after November 1993, respectively, in order to determine whether the use of a reduced dose would both maintain tumor control and reduce post-treatment cranial nerve complications. Patients aged ≥ 18 years old, acoustic neuroma determined by CT or MRI, the largest tumor diameter ≤ 4cm. In addition, patients are: ① not or refuse surgery, and appropriate radiosurgery. ② tumor invasion is a functional ear. ③ tumor exists on both sides. ④ or as previously had surgery, there are tumor remnants or recurrence. A total of 42 patients used a “standard dose regimen,” a tumor marginer