MRI定位方法对伽玛刀治疗原发性三叉神经痛的影响价值

Application of MRI localization method on Gamma knife radiosurgery for primary trigeminal neuralgia

目的探讨伽玛刀治疗原发性三叉神经痛患者时MRI定位的最佳成像序列，评价定位技术对疗效的影响价值。方法两组共60例原发性三叉神经痛患者，A组30例采用常规法定位，头架基础环平听眦线，sE序列2~3mm薄扫；B组30例采用改良3D TOF法定位，头架基础环平行于听眦线向前开放15°夹角所形成的直线为扫描基准线，3D TOF序列扫描。输入图像资料进行定位规划后，以三叉神经根为靶点进行伽玛刀治疗。随访两组患者近期和远期疗效，进行统计分析。结果近期疗效两组无明显统计学差异；远期并发症和复发率比较，两组有统计学差异。结论改良3D-TOF定位法能完全清晰的显示三叉神经根，有利于伽玛刀的准确定位，对避免并发症及降低复发率有重要价值，可作为伽玛刀治疗原发性三叉神经痛的常用定位法加以推广应用。

Objective To investigate the optimal sequences of primary trigeminal neuralgia（ PTN）, and evaluate the therapeutic efficacy of Gamma knife radiosurgery on PTN. Methods Sixty patients with PTN were divided into 2 groups ,30 patients in group A used conventional localization method, stereotactic frame was parallel with OM line, SE sequence was taken into scanning;30 patients in group B used improved 3D-TOF localization method, stereotactic frame was parallel with OM line,the angle between stereotactic frame and scanning baseline was 15° ,3D-TOF sequence was taken into scanning. The images of patients were imported and position planning was taken at the same time, and then the Gamma knife radiosurgery therapy took the root of trigeminal nerve as the target. The data of follow-up was used to analyze the short-term and long-term efficacy. Results There was no significant difference in the short-term efficacy between these two groups; while the long-term efficacy of the group which used improved 3D-TOF localization method was better than that of the group which used SE sequence ,they had significant difference. Conclusion Improved 3D-TOF localization method can help achieve accurate orientation of Gamma knife, which provides clear images of trigeminal nerves and is of great importance to avoid the risk of complications and reduce the reoccurrence rate. It can be used as the conventional localization method for Gamma knife radiosurgery in the treatment of PTN.