New Orleans — Lateral infrabrow injection of botulinum toxin type A (Botox/Botox Cosmetic, Allergan) may be considered as a less invasive alternative to blepharoplasty in patients seeking treatment for mild-to-moderate dermatochalasis, says Joel L. Cohen, M.D.
Dr. Cohen, in collaboration with Steven H. Dayan, M.D., evaluated the effects of botulinum toxin type A injection on temporal brow elevation in a prospective, dose-comparison study. Dr. Cohen is in practice in Englewood, Co., and Denver, and he is an assistant clinical professor of dermatology, University of Colorado, Englewood. Dr. Dayan is a facial plastic surgeon in practice in Chicago and clinical assistant professor of otolaryngology-head and neck surgery, University of Illinois, Chicago.
The results of the low-dose botulinum toxin injections were relatively impressive, Dr. Cohen says.
After two weeks, 32 percent of patients treated with the eight-unit dose and 48 percent of those in the 12-unit group were categorized as responders. At the 20-week visit, response rates were 21 percent in both dose groups.
Analyses of results from patient ratings using the same scale showed the eight-unit dose was associated with a higher responder rate than the 12-unit dose at two weeks (37 vs. 24 percent), while at 20 weeks, 7 percent of patients in the eight-unit group and 21 percent of those treated with the higher dose were responders.
Secondary endpoints, including patient evaluations of improvement from baseline, appearance/attractiveness/confidence ratings and overall treatment satisfaction, also pointed to benefits of both doses. At the end of the study, 43 percent of subjects in the eight-unit group and 50 percent of those who received the 12 units of botulinum toxin type A were satisfied or very satisfied with their treatment.
"This is not an appropriate substitute for blepharoplasty in patients with severe dermatochalasis causing functional impairment. However, in carefully selected patients with mild-to-moderate eyelid redundancy who are not candidates for incisional surgery or who wish to avoid or delay it, botulinum toxin type A injection may be a reasonable option. Not all patients will respond, but a trial seems justified considering the potential for benefit along with the safety and relatively low cost of the doses used in this application," Dr. Cohen says.
Efficacy of botulinum toxin injection for achieving browlift has been reported by other investigators, although Dr. Cohen notes the current study is distinguished by its larger patient population and dose-comparison design.
In that regard, no significant differences were noted between the two doses in the primary efficacy endpoint at any visit. However, significant differences favoring the 12-unit dose were noted at weeks two and eight in subject ratings of feelings of attractiveness and satisfaction with appearance, and overall, for the majority of the outcome measures, there was a numeric difference favoring the higher dose.
Both doses were associated with similarly good safety profiles. The only adverse events recorded that were
considered possibly treatment-related were in the 8-unit group and included mild injection site sensitivity to touch in one patient and mild fasciculations of one eyelid in another individual.
"The results of this trial suggest the 12-unit does may provide better results, but a larger study would be needed to investigate any true dose-response relationship. The excellent safety of the 12-unit regimen supports its further evaluation," Dr. Cohen says.