Treatment of Frey's Syndrome Patients with Botulimum Toxin A

ABSTRACT

PURPOSE: Frey's syndrome is a common complication after parotid surgery and characterized by gustatory sweating and flushing in the periauricular area during meals. Although a variety of methods were proposed to prevent this postoperative problem, they were unsatisfactory. We used botulinum toxin A to treat 9 patients with Frey's syndrome and investigated the duration effect after the injection. METHODS: Nine patients became the object of study about the effect of botulinum toxins as treatment of Frey's syndrome. Age of patients ranged from 25 to 78 years (mean, 43.7 years). Six of nine patients had both symptoms of gustatory sweating and flushing. And the others had only gustatory sweating symptom. Using Minor starch iodine test, the affected skin area was detected, and it was marked by 1 cm2 sized grid appearance. After application of EMLA cream on the gustatory sweating area, botulinum toxin A was injected intracutaneously into the affected skin area (2.5 U/cm2). Patients were followed up from six to fifteen months (mean, about 12 months) and asked about improvement of their symptoms. RESULTS: The treatment with botulinum toxin A had an effect within 2 days after the injection. Six months after injection, gustatory sweating disappeared completely in all patients, and 5 of six patients who had gustatory flushing improved in their symptom. At the last follow-up, no patients complained of recurrent gustatory sweating and flushing except one. One patient, seven months after initial injection, was retreated with botulinum toxin A because of recurrence, and the result was successful. The duration of the effect after botulinum toxin A treatment was ranged from seven to thirteen months. One patient in our series experienced the upper eyelid weakness as adverse effect, but it improved spontaneously. CONCLUSION: Local injection of botulinum toxin A is an effective, safe and long-lasting method for treatment of Frey's syndrome. Hereafter, however, additional study is required to evaluate the duration effect of botulinum toxin A as to frequency in use and dosage