Microvascular decompression for vertebrobasilar dolichoectasia-related primary trigeminal neuralgia: surgical approaches, technical considerations, and clinical outcomes.

Objectives To investigate the surgical strategies, technical aspects, and clinical outcomes of microvascular decompression (MVD) in treating primary trigeminal neuralgia (PTN) associated with vertebrobasilar dolichoectasia (VBD). Methods A retrospective analysis was conducted on 34 consecutive VBD-related PTN patients treated by a single neurosurgeon at China-Japan Friendship Hospital from January 2020 to April 2025. VBD compression patterns were classified into two types: Type I: Imaging showing significant brainstem deformation and obliteration of the arachnoid space by VBD (n = 16, 47.1%). Type II: Imaging confirming VBD with minimal or no brainstem deformation and preserved arachnoid space (n = 18, 52.9%). Type-specific MVD techniques were applied: a four-step approach for Type I and a three-step approach for Type II. Outcomes were assessed using the Barrow Neurological Institute Pain Intensity Scale (BNI) during follow-up (range: 2-64 months). Results Among 1,214 PTN patients treated during the study period, 34 (2.8%) had VBD-related PTN. Preoperative BNI grades: Grade V in 8 patients (23.5%), Grade IV in 26 patients (76.5%). Comorbid cranial neuropathies were present in 17.6% (6/34) of patients. Postoperative outcomes: BNI Grade I in 91.2% (31/34), BNI Grade II in 8.9% (3/34). The overall success rate (BNI ≤ II) was 100%. Conclusion VBD-related PTN is a rare condition characterized by severe refractory pain. Tailored MVD strategies, based on VBD compression morphology (Type I vs. Type II), provide a safe and effective surgical approach, resulting in excellent pain relief.