Complexity of arachnoid adhesions dictating the outcome of microvascular decompression for trigeminal neuralgia

Multiple techniques have been used to treat trigeminal neuralgia (TGN), including pharmacotherapy, radiosurgery, rhizotomy and microvascular decompression (MVD). Blood vessels are considered to be the most common cause of offense and compression to trigeminal nerve. We aimed to determine the causes of classic TGN and efficacy of MVD. This retrospective, cross-sectional study assessed the data of 53 patients, who underwent MVD at the Department of Neurosurgery, Punjab Institute of Neurosciences, Lahore, Pakistan, from May, 2022 to December, 2023. Information regarding patient demographics, clinical presentation, Barrow Neurological Institute Facial Pain Score (BNI-FPS), intra-operative findings, and postoperative complications were analyzed. The mean age at presentation was 44.33 ± 11.71 years. Unilateral facial pain was the consistent clinical presentation among all patients, with right-sided involvement in 67.92% patients. All patients had involvement of at least two divisions of trigeminal nerve; maxillary and mandibular nerve in 84.91% and 71.70% cases, respectively. BNI-FPS Grade-IVb was found among 49.09% patients on presentation. Arachnoid adhesions, superior cerebellar artery and superior petrosal vein were the most common causes of compression in 71.70%, 50.94% and 43.40% cases, respectively. About 94% patients were discharged home on first post-operative day without complications and with BNI-FPS Grade-I. Microvascular decompression is highly advocated in classic cases of TGN. In the absence of grossly visible offending vascular structure, arachnoid adhesions should be the thorough focus of address.