[Severe Frey syndrome after parotidectomy: treatment with botulinum neurotoxin type A]

Based upon an inception cohort of 30 patients with severe Frey's syndrome, after conservative parotidectomy, the technique and the results of intracutaneous injection of botulinum toxin type A are presented. The skin surface involved with Frey's syndrome was managed with intracutaneous injection of 2.5 international units of botulinum toxin type A per square centimeter. A minimum follow-up of 16 months was achieved. The only adverse side effect encountered was a temporary paresis of the upper lid noted in 2 patients. Frey's syndrome vanished within 2-5 days from the intracutaneous injection of botulinum toxin type A. Frey's syndrome was controlled in 53.2% of cases (17/30) after the initial injection of botulinum toxin type A. Five of the 13 patients with recurrence of Frey's syndrome elicited to undergo a watch and wait policy due to the lack of discomfort induced by the recurrence. The remaining eight patients with recurrence of Frey's syndrome were successfully managed with a secondary intracutaneous injection of botulinum toxin type A. Such preliminary data, together with the review of the literature suggests, that the intracutaneous injection of botulinum toxin type A should now be the first line treatment option in patients with severe Frey syndrome.