Risk factors for postoperative recurrence after full-endoscopic microvascular decompression for trigeminal neuralgia: a retrospective study and predictive nomogram

Background: Full-endoscopic microvascular decompression (fE-MVD) is an emerging treatment option for trigeminal neuralgia (TN). However, the risk factors associated with postoperative recurrence of TN after fE-MVD procedure remain controversial. The aim of the present study was to summarize the surgical technique of fE-MVD for the treatment of TN and to develop a predictive model for recurrence at 1 year postoperatively based on independent risk factors.

Methods: A total of 124 consecutive patients with TN who underwent fE-MVD procedure were enrolled in this study between December 2008 and July 2022. Imaging data such as the area of cerebellopontine angle (CPA), the length of trigeminal cisternal segment, and the angle of trigeminal nerve (TGN) were measured from preoperative magnetic resonance imaging (MRI). Patients were randomly divided into a training set and a validation set according to the 7:3 ratio, respectively. Variables that were significant in the univariate logistic analyses were, subsequently, included in the multivariate logistic regression analyses in training set. Then, we developed a predictive nomogram for the 1-year recurrence of TN for patients who treated with fE-MVD.

Results: All 124 patients experienced clinically significant pain relief (Barrow Neurology Institute (BNI) I-II) after fE-MVD. 124 patients had a follow-up time of more than 1 year, with 14 cases of recurrence. In the univariate analysis, the patients' responsible vessels of non-arterial, clinical features of atypical, and CPA area ratio (healthy/affected side) >1 were found to be significantly associated with recurrence of TN after fE-MVD. Multivariate logistic regression analyses result showed that the patients' responsible vessels of non-arterial (odds ratio (OR) = 21.067, 95% confidence interval (CI): 1.942-228.575), clinical features of atypical (OR = 9.027, 95% CI: 1.135-71.777), and CPA area ratio >1 (OR = 19.522, 95% CI: 2.906-131.160) were independent predictors of TN recurrence. Based on the independent predictive factors, we developed a predictive nomogram that predicts the 1-year recurrence of TN after fE-MVD. In the receiver operating characteristic (ROC) curve analysis, the area under the curve (AUC) of the nomograms for 1-year recurrence associated with optimal candidates prediction was 0.910 in the training set and 0.859 in the validation set.

Conclusions: FE-MVD for the treatment of TN is a safe, reliable and effective procedure. Patients' responsible vessels of non-arterial, clinical features of atypical, and CPA area ratio (healthy/affected side) >1 are key risk factors associated with 1 year postoperative recurrence of TN after fE-MVD. Finally, we have developed a nomogram to predict the 1-year recurrence of TN for patients who treated with fE-MVD, which can be used to provide advice for patients after fE-MVD.