MATERIAL and METHODS: A total of 425 patients who underwent surgery between 1991 and 2011 for idiopathic TN were included in this study. Pain outcome was graded using the Barrow Neurological Institute pain scale and success was defined as complete pain relief without medication. A Kaplan-Meier survival curve was generated. Univariate analysis and Cox proportional-hazards regression were performed to identify factors associated with the maintenance of long-term pain relief.

RESULTS: The cure rate was 89.3% at 1 year, 80.5% at 3 years, 75.6% at 5 years, and 71.2% at 8 years. Typical clinical presentation, arterial vessel compression, and age ? 60 years at the time of surgery were independent predictors of an excellent outcome. Gender, side, branches involved, symptom duration, hypertension, previously failed surgery, and number of conflicted vessels had no prognostic value. A total of 36 patients (8.47%) developed permanent cranial nerve injury and general complications and the mortality rate was 0.24%.

CONCLUSION: MVD has positive effects for TN treatment, with persistent pain relief achieved in 71.2% of patients 8 years after the procedure. Long-term pain remission may be related to typical clinical presentation, an arterial conflicted vessel, and age ? 60 years at the time of surgery. Keywords : Trigeminal neuralgia, Microvascular decompression, Outcome