Reduced effect of percutaneous retrogasserian glycerol rhizolysis in trigeminal neuralgia affecting the third branch.

INTRODUCTION: The objective of this study was to determine the long-term efficacy of percutaneous glycerol rhizolysis of the trigeminal ganglion for treating patients with trigeminal neuralgia and search for predictors associated with (long-term) benefit to improve patient selection. METHODS: A retrospective study in 60 consecutive patients treated with percutaneous glycerol rhizolysis of the trigeminal ganglion for trigeminal neuralgia. Charts were reviewed in combination with follow-up by questionnaire (n = 55, 92% response). RESULTS: Initial pain relief was achieved in 92% of the patients. Pain-free survival was 59% of the patients at 12 months and 53% at 24 months. Most common side effects were hypesthesia (15%), dry eye (5%), and meningitis (2%). In patients without involvement of the third branch of the trigeminal nerve, the initial effect was 79%, of which 90% achieved more than 2 years pain-free survival, compared with 97% initial effect and less than 40% pain-free survival of more than 2 years when the third trigeminal branch was involved. DISCUSSION: The present study demonstrates that involvement of the third branch is a negative predictor for long-term outcome in percutaneous glycerol rhizolysis of the trigeminal ganglion in patients with classical trigeminal neuralgia. However, in the absence of third-branch involvement, glycerol rhizolysis yields excellent long-term results when initial positive effect is obtained.