伽玛刀治疗原发性三叉神经痛的临床研究

Clinical study of gamma knife radiosurgery for primary trigeminal neuralgia

目的 探讨原发性三叉神经痛伽玛刀 (γ 刀 )治疗的临床效果及相关因素。方法 三叉神经痛患者 12 6例 ,其中男 5 7例 ,女 6 9例 ,平均年龄 6 1.2岁 (2 6～ 83岁 )。右侧 6 8例 ,左侧 5 4例 ,双侧4例 ;Ⅱ、Ⅲ支痛 80例 ,Ⅰ、Ⅱ、Ⅲ支痛 16例 ,Ⅰ、Ⅱ支痛 10例 ,Ⅱ支痛 6例 ,Ⅲ支痛 14例。定向仪框架安装需特定位置 ,即框架的Y轴与患者颅基底线平行 ,与OM线向前夹角 10 .3°± 1.9°,X轴对准颅中线 ,框架两侧保持水平位。MRIT1加权和 3D FASE影像轴、冠序列无间距扫描定位 ,层厚 1～ 2mm。照射靶点选择在三叉神经根桥脑进入区 ,单一 4mm准直器 ,中心剂量 70～ 90Gy ,5 0 %等剂量线限定靶点 ,2 0 %等剂量线限定在桥脑表面。结果 平均随访期 4 2个月 (9～ 77个月 )。优 (10 0 %缓解 )为 75例 (5 9.5 % ) ,良 (缓解 80 %以上 ,无需药物 )为 35例 (2 7.8% ) ,有效 (缓解 5 0 %～ 80 % ,需要少量用药 )为 7例 (5 .6 % ) ,无效 9例 (7.1% ) ,总有效率为 92 .9%。疼痛缓解后复发 10例 (8.6 % )。无效和复发的患者在第二次γ 刀治疗后有效率 94 .8%。 12例 (9.5 % )出现面部麻木感 ,其中二次治疗者5例 ,客观检查面部痛、触觉无明显减退 ,1例 (二次治疗者 )张口轻度受限 ,余者无三叉神经运动障碍 。

Objective To study the clinical effect of gamma knife radiosurgery for primary trigeminal neuralgia.Methods 126 patients, 69 women and 57 men with a mean age of 61.2 years(range 26～83 years), underwent radiosurgical treatment of trigeminal neuralgia with the gamma knife. Stereotactic frame was attached to patients' skull according to the skull baseline, the angle between skull baseline and orbitomeatal line (OM line) was 10.27°±1.89°. Stereotactic T 1-weighted and 3D-FASE MRI with 1～2 mm slice interval was performed to identify trigeminal nerve from pons to Meckel's cave. Radiosurgery target was localized at the sensory root of trigeminal nerve entry zone of pons. A single 4mm collimator was used, with maximal dose 70～90 Gy , 50% isodose curve limited target. The brainstem surface dose was not more than 20%.Results The follow-up period ranged 9～77 months(mean 42 months). 75 cases (59.5%) were complete pain relief, 35 cases (27.8%) were pain relief by more than 80% and 7 cases (5.6%) were pain relief by more than 50%. The total effective rate was 92.9%. 9 cases (7.1%) were ineffective results. 10 cases (8.6%) had recurrence of pain after an initial complete pain relief. Complete pain relief was achieved in all ineffective and recurrent cases after second gamma knife operation. Only 12 cases ( 9.52%) complained facial numbness, without physically neurological deficit. One case had slight dysmasesis. No other complications appeared, nor mortality.Conclusion Gamma knife radiosurgery appears to be a noninvasive, safe, and effective therapy for trigeminal neuralgia.