Percutaneous retrogasserian glycerol rhizotomy in the treatment of tic douloureux associated with multiple sclerosis

OBJECTIVE: Patients with multiple sclerosis (MS) have a relatively high incidence of tic douloureux (TD) and often do not tolerate medical therapy well. The minimally invasive nature of percutaneous retrogasserian glycerol rhizotomy (PRGR) renders it ideal for first-line surgical treatment of TD. We sought to ascertain the benefits of PRGR in patients with MS and to determine whether hypalgesia after PRGR correlates with efficacy. METHODS: We assessed 97 glycerol procedures performed in 53 patients followed prospectively for treatment of TD associated with MS. Factors assessed included degree of pain relief, postoperative hypalgesia, procedural morbidity, medication use, time to pain recurrence, and number and type of subsequent procedures. RESULTS: Complete pain relief was obtained in 78% of patients after the initial glycerol injection, and partial relief was obtained in 13% of patients. Long-term follow-up (mean, 81 mo) demonstrated a recurrence rate of 59%, with a mean time to recurrence of 17 months. Actuarial recurrence rates were 50% at 12 months and 60% at 24 months. Twenty-four patients underwent a second or subsequent PRGR for recurrent pain and achieved similar rates of pain relief and time to recurrence. Facial sensory loss was associated with a higher likelihood of pain relief (P < 0.05), with longer time to pain recurrence (P < 0.05), and with decreased use of medication after surgery (P < 0.01.) CONCLUSION: PRGR is an effective, low-morbidity surgical procedure in the management of TD complicating MS. The presence of facial sensory loss after PRGR is associated with prolonged efficacy.