Microsurgical partial trigeminal rhizotomy for multiple sclerosis-associated trigeminal neuralgia: a retrospective single-center series of 16 patients

Background Trigeminal neuralgia associated with multiple sclerosis may arise from demyelination within the pons or trigeminal root entry zone rather than an isolated neurovascular conflict. This study describes early outcomes after microsurgical partial trigeminal rhizotomy in patients with medically refractory multiple sclerosis-associated trigeminal neuralgia. Methods We retrospectively reviewed 16 consecutive patients treated with retrosigmoid partial trigeminal rhizotomy from 2022 to 2026. MRI and operative findings were reviewed for demyelination, vascular contact, root deformation, and other structural pain generators. Pain was graded using the Barrow Neurological Institute scale. Four patients underwent incisional biopsy of the cisternal trigeminal root. Results All 16 patients were pain-free without medication at discharge (BNI I). No coexisting vascular compression or root deformation was documented on MRI or intraoperatively. Facial numbness occurred in all patients; early V1 recovery was documented in 14. No corneal-reflex reduction, dry-eye syndrome, dysesthesia, or anesthesia dolorosa was documented in available records. Two patients developed clinically significant pneumocephalus after surgery in the sitting position. Biopsy findings were compatible with, but not diagnostic of, demyelinating trigeminal neuropathy. Conclusions Partial rhizotomy achieved complete immediate pain relief in this selected series. Follow-up intervals were approximate because exact dates and systematic post-discharge assessments were not consistently available; longer prospective follow-up is required.