Purpose

We aimed to study the long-term efficacy, prognostic factors and complications associated with the GKRS for trigeminal neuralgia.

Methods and Materials

Prospectively created database was analyzed for these patients. We created an Artificial neural Network – using Multilayer perceptron model in SPSS 23 by including all variables whose p value were<0.5 in univariate analysis.

Results

A total of 36 patients were included in the study. Patients pain free at 6 months were 25(69.44%), which reduced to 6(40 %) at 6 years. Median time to pain relief was 18.5 days. Only 5(13.88%) of them developed new onset or worsened numbness post Gamma Knife radio surgery. Median radiation dose was 80 Gy (prescribed at 100 percent isodose line). 1st GKT (P value < 0.05) and post GKT numbness (P value < 0.05) were the only factors favouring good outcome.

Prior history of MVD was associated with poor pain relief post GKRS although p value was not significant (p = 0.136). ANN model could predict with 90.0 percent accuracy the favourable or unfavourable response on 11 Tested cases. In ANN model, a greater number of Pre GKT medications, previous MVD history, V2 dermatome involvement and negative history of post GKT numbness were negative prognostic factors.

Conclusions

Lesser number of pre GKRS drugs used, involvement of V1 dermatome, post GKT numbness are favourable prognostic factors. Also, history of failed MVD for trigeminal neuralgia is associated with poor outcome. Repeat GKRS failed to show improvement in BNI grades.

中文翻译：

---

伽玛刀放射外科在三叉神经痛中的作用——使用人工神经网络模型对其长期结果和预测

目的

我们旨在研究与 GKRS 治疗三叉神经痛相关的长期疗效、预后因素和并发症。

方法和材料

为这些患者分析了前瞻性创建的数据库。我们创建了一个人工神经网络——在 SPSS 23 中使用多层感知器模型，通过在单变量分析中包含 p 值 <0.5 的所有变量。

结果

该研究共包括 36 名患者。6个月无痛患者25人（69.44%），6年后减至6人（40%）。疼痛缓解的中位时间为 18.5 天。其中只有 5 人（13.88%）在伽玛刀放射手术后出现新发麻木或麻木加重。中位辐射剂量为 80 Gy（按 100% 等剂量线规定）。第一次 GKT（P 值 < 0.05）和 GKT 后麻木（P 值 < 0.05）是有利于良好结果的唯一因素。

尽管 p 值不显着 (p = 0.136)，但 MVD 的既往史与 GKRS 后疼痛缓解不佳有关。ANN 模型可以以 90.0% 的准确率预测 11 个测试案例的有利或不利响应。在 ANN 模型中，更多的 Pre GKT 药物、既往 MVD 病史、V2 皮节受累和 GKT 后麻木的阴性病史是不利的预后因素。

结论

使用较少数量的 GKRS 前药物、V1 皮节受累、GKT 后麻木是有利的预后因素。此外，三叉神经痛 MVD 失败的历史与预后不良有关。重复 GKRS 未能显示 BNI 等级的改善。