Introduction: Percutaneous glycerol rhizotomy (GR) is used to treat trigeminal neuralgia (TN) with reported pain relief lasting 2-3 years. GRs performed at a single center were retrospectively analyzed to compare pain relief and durability between initial and subsequent procedures.
Methods: Between 1998 and 2010, 547 patients with TN underwent 713 GRs. Outcomes were available for 652 GRs (91.4%) and 61 GRs (8.6%) were excluded for limited follow-up. Comparisons were made between 503 initial GRs (GR1) and 149 subsequent GRs (GR 2+). Fisher’s exact test was applied to assess initial pain relief using the Boulder-Stanford (B-S) pain relief scale. Durability was assessed by median time to treatment failure (B-S scale 3 or 4) for all procedures that achieved good pain relief outcomes (B-S 1 or 2, n=514, 361 failures, 153 censored). Predictors of failure were assessed by applying multivariate Cox-regression analyses adjusting for multiple procedures within same patient.
Results: Pain relief outcomes in first GR1 were excellent in 327(65.0%), moderate in 59(11.7%) , mild in 51(10.1%) , and unchanged in 66(13.1%). In GR2+ 111 had excellent (74.5%), 17 (11.4%) had moderate, 5 (3.4%) had mild, and 16 had unchanged outcomes(10.7%) (p=0.031). There was a trend towards improved durability with prolonged median time to failure in GR2+ (805 days; 95% CI: 648-1,159) as opposed to GR1 (579 days;95% CI: 450-722), however this was not significant (p=0.0627). Multivariate analysis showed prior GR to be an independent predictor of durability as patients with 2 or more GRs were 21% less likely to fail than patients with single GR(hazard ratio 0.79, 95% CI 0.630-0.98, p=0.032). Age, gender, duration of TN symptoms, progression of dermatomes involved, and history of other surgical treatments of TN were all non-significant.
Conclusions: Patients experienced better pain relief outcomes and improved durability with additional glycerol rhizotomies beyond the initial treatment.
Patient Care: This study provides further evidence of the benefit of repeat percutaneous rhizotomy in patients with TN.
Learning Objectives: To understand the indications for glycerol rhizotomy in patients with recurrent trigeminal neuralgia.
To determine the efficacy of GR to treat conventional TN in patients with recurrent symptoms.