摘要目的 分析伽玛刀治疗高龄大型听神经瘤的中长期疗效,探讨伽玛刀治疗大型听神经瘤的适应证.方法 应用Leksell伽玛刀治疗高龄大型听神经瘤50例,肿瘤最大径为31.0～63.0mm,肿瘤平均体积为(14.8±8.0)cm3.照射肿瘤的中心剂量为22.0～28.0 Gy,平均周边剂鼍为(12.3±0.9)Gy.随访时间为68～138个月.结果 46例健在,4例死亡.伽玛刀术后45例肿瘤缩小,2例无变化,3例增大,肿瘤控制率为94%(47/50).14例保留有效听力,其余听力无变化或下降.2例出现轻度面瘫,18例出现面部不适或麻木,7例出现脑积水行分流手术.结论 伽玛刀对高龄、脑干受压不明显、肿瘤内有部分囊性变的大型听神经瘤(最大径≤40mm)有良好长期控制作用.

abstractsObjective To evaluate the effect of Leksell Gamma Knife(LGK)on elderly patients with large vestibular schwannomas(VS)and to summarize the indiclltions for LGK in patients with large VS.Methods From July 1994 to July 2000,50 elderly patients(age range:60.0-81.0 years)with large VS were treated bv LGK as primary treatment modality.The maximal tumor diameter ranged from 31.0 to 61.0 mm[mean,(36.0±6.1)mm]and mean tumor volume was(14.8±8.0)cm3(range,7.5-54.0 cm3).The maximal dose irradiated to tumor ranged from 22.0 to 28.0 Gy[mean:(25.0±1.6)Cy]and the mean tumor marginal dose was(12.3±0.9)Gy(range,9.5-14.OCy).The mean follow-up duration wast(86±12)months(range:68-138 months).Results of the 50 patients with follow-up data,4 Were deceased and 46 survived.Two patients with giant VS died at 6 and 9 months post-LGK respectively because of tumor swelling.Another two pailents died of stroke or heart attack at 3 years and 4 years after LGK respectively.but their tumors decreased in volume.Clinical response:hearing:14(28%)pailents preserved useful hearing as pre-LGK;32 patients had unchanged or deteriorated hearing.Facial palsy:two patients developed mild facial palsy at 4 and 8 months respectively,one of them recovered and another improved later.Seven patients developed hydrocephalus around 6 months post-LGK and had V-P shunt.Eighteen patients had deteriorated facial unmbness because of tumor swelling,15 of them improved 3 years later.Tumor response:in 46 surviving patients,43 tumors decreased markedly in.size,2 tumors remained stable in volume,1 tumor progressed at five years and had second LGK.In this series tumor control rate was 94% (47/50).Conclusion LGK provides an effective treatment for some selected large VS(maximal diameter≤40 mm)in elderly patients,especially when the brain stem compression was not obvious and VS had non-enhanced area or small cysts within tIle tumor on contrast MRI.