Predictors of successful microvascular decompression surgery in patients with classical trigeminal neuralgia according to the neuroimaging data

Trigeminal neuralgia presents significant challenges in neurosurgery, with patients responding variably to Microvascular Decompression (MVD). Advanced neuroimaging techniques, specifically MRI using the Constructive Interference in Steady State (CISS) sequence and Diffusion Tensor Imaging (DTI), have emerged as promising tools in predicting the outcomes of MVD. Aim of the study was to determine neuroimaging predictors of successful microvascular decompression surgery in patients with classical trigeminal neuralgia. Material and methods. This retrospective study analyzed 58 patients who underwent microvascular decompression for classical trigeminal neuralgia at the Federal Neurosurgical Center in Novosibirsk, Russia, between January 2017 and December 2021. Outcomes were assessed by the Barrow Neurological Institution (BNI) scale. Preoperative neuroimaging with CISS and DTI was used to evaluate neurovascular conflict severity, nerve diffusion and other criteria. Results. 79.3 % (BNI I & II) of patients were practically free of pain postoperatively, in which 65.5 % (BNI I) had successfully completely recovered from the procedure with no pain, and 13.8 % (BNI II) had a good outcome. And the study found a significant correlation between favorable MVD outcomes and higher Sindou grades 2 and 3, indicating more severe neurovascular conflict (p < 0.001). Also significant differences were observed in outcomes based on fractional anisotropy values on symptomatic nerve (p = 0.029). Discussion. Anatomical factors which measured by MRI had limited impact on outcomes, while Sindou grading showed a significant correlation with surgical outcomes, and higher fractional anisotropy values were associated with poorer outcomes. Conclusions. The investigation of neuroimaging predictors for MVD surgery outcomes in patients with trigeminal neuralgia, received from CISS-sequence imaging and pre-treatment DTI, indicates the importance of estimation of severity of vascular compression in surgical planning and the predictive value of fractional anisotropy values from DTI for preoperative assessments.

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