Treatment of Lateral Periorbital Lines with Different Dilutions of IncobotulinumtoxinA.

IncobotulinumtoxinA is a botulinum neurotoxin type A that is free from complexing proteins and is used in various therapeutic indications and aesthetic medicine. It is approved for the treatment of glabellar frown lines in the United States. In Europe, it is also approved for the treatment of lateral periorbital lines (crow's feet) and for the combined treatment of upper facial lines, including glabellar frown lines, crow's feet, and horizontal forehead lines. In the present study, incobotulinumtoxinA was injected at two different dilutions to treat female subjects aged 40 to 50 years who had moderate-to-severe lateral periorbital lines at maximum contraction according to a score of 2 or 3 points on the 5-point Merz Aesthetics Scales (MAS). For Group 1 (n=20), 50U of incobotulinumtoxinA were reconstituted with 1.60mL of 0.9% NaCI, and for Group 2 (n=20), a reconstitution volume of 0.55mL was used. Merz Aesthetics Scales scores were markedly improved by at least one point in both groups at one month and three months. The mean Merz Aesthetics Scales scores at one month were 0.4 and 0.6 points for Group 1 and Group 2, respectively, corresponding to a mean improvement of 2.0 and 1.8 points compared with baseline, respectively. No significant differences in efficacy and tolerability of incobotulinumtoxinA were seen between the two dilutions at any time point.