The management of hyperfunctional facial lines with botulinum toxin. A collaborative study of 210 injection sites in 162 patients.

Objective: To determine the optimum dose and efficacy of botulinum toxin injections in the management of hyperfunctional facial lines.

Design: This study included 210 hyperfunctional facial sites in 162 different patients. The patients had preinjection and postinjection photographic documentation and ratings on a 4-point qualitative evaluation scale of lines at rest and with action. The patients then had botulinum toxin type A injections via a monopolar hollow bore, Teflon-coated electromyographic needle into the facial muscles associated with the hyperfunctional lines. The total dose for each region of 1.25 to 25 U was divided into 1.25- to 5-U aliquots representing 0.1 to 0.2 mL per injection site, depending on the site and the prior experience with that patient on using toxin. The patients had their reevaluation at 2 to 3 weeks after injection. Patients returned for further follow-up when the therapeutic effect diminished.

Patients: One hundred sixty-two patients had 210 hyperfunctional sites evaluated and injected. The group consisted of 25 male patients and 137 female patients ranging in age from 21 to 78 years with a mean (+/-SD) of 46.1 (+/-1.98) years. All patients had cosmetically troubling hyperfunctional lines involving the forehead, glabella, crow's feet (lateral canthal lines), nasolabial area, platysma, and mentalis region.

Results: All patients had an effect of toxin within the first 24 to 72 hours. Ninety-five percent of the patients treated had cosmetic improvement of unsightly facial lines or contractions. The best results were achieved in management of the forehead lines, followed by glabella, crow's feet, and nasolabial. The dose for forehead lines was 5 to 25 U (mean +/- SD, 17.3 +/- 6.2 U); glabellar lines, 5 to 20 U (mean +/- SD, 11.1 +/- 3.1 U); crow's feet, 5 to 15 U (mean +/- SD, 6.2 +/- 1.6 U); nasolabial, 2.5 to 5 U (mean +/- SD, 3.12 +/- 1.2 U); and platysma, 10 to 20 (mean +/- SD, 15 +/- 4.0 U). Evaluation by age and site suggested a trend of increased toxin dose with increased age. Effects of the toxin are usually seen 24 to 72 hours after injection, and last from 3 to 6 months, whereon the increased muscular activity returns, as do the hyperfunctional lines. The only morbidity was related to temporary mild weakness of other adjacent facial muscles. There were no systemic side effects noted.

Conclusion: Botulinum toxin is a safe and important adjunctive technique for the management of patients with symptomatic hyperfunctional facial lines.