Follow-up of patients with essential blepharospasm who underwent eyelid protractor myectomy at the Mayo Clinic from 1980 through 1995

Purpose: To determine the efficacy of eyelid protractor myectomy (subtotal excision of the orbicularis oculi, the corrugator supercilii, and the procerus muscles) for the treatment of essential blepharospasm, and to evaluate the need for and the effectiveness of botulinum toxin (BT) injections in these patients. Methods: The medical records of all patients who underwent eyelid protractor myectomy at the Mayo Clinic (Rochester, MN) from 1980 through 1995 were reviewed. The Health Status Questionnaire(R) was used to assess overall medical and mental health, and a questionnaire specific to eyelid spasms was developed. Results: Fifty-four white patients, of whom 32 (59%) were women, underwent myectomy. The average age at diagnosis of essential blepharospasm was 64 years (median, 65 years; range, 43 to 84 years), whereas the average age at the rime of myectomy was 66 years (median, 66 years; range, 51 to 85 years). Of the 14 patients who were treated with BT injections before myectomy, the average interval between the initial injection and surgery was 21 months (median, 20 months; range, 2 to 51 months). Patients who had been treated with BT injections before myectomy were more likely to receive injections postoperatively than were those patients who had not been treated with BT (p<0.001). Twenty patients were treated with BT injections after myectomy; the overall probability of receiving BT five years after surgery was 46%. Time from myectomy to treatment with BT varied considerably: mean, 880 days; median, 659 days; range, 3 to 4221 days. Postoperative follow-up for those patients who did not receive BT after myectomy ranged from 2 to 5935 days (mean, 2354 days; median, 1722 days). Although the probability of receiving BT injections after myectomy was not associated with age or sex, there was a significant association with the time interval during which the myectomy had been performed (related to the availability of BT as an adjunctive therapy). Of the 41 patients who were alive when the study was conducted, 32 (78%) completed a follow-up survey. Thirty of those (94%) said myectomy provided shortterm and long-term benefits. Of the 11 patients who received BT injections before and after myectomy, six (55%) said the toxin was more effective in ameliorating eyelid spasms after surgery and four (36%) required injections less frequently after myectomy. Results from the Health Status Questionnaire(R) showed no significant differences between patients who underwent myectomy and control subjects. Conclusions: Eyelid protractor myectomy provides subjective benefit to patients with essential blepharospasm and decreases the long-term need for BT injections in approximately 50% of these patients. Although the probability of receiving postoperative BT paralleled its availability, patients who received both preoperative and postoperative BT perceived either increased efficacy of the toxin injections, longer-lasting effects, or both, after myectomy. Patients with severe disability from blepharospasm benefited more from myectomy than did patients with relatively mild symptoms.