Management of the ageing eyebrow and forehead: an objective dose–response study with botulinum toxin

OBJECTIVE: To determine if clinical use of two different doses of botulinum exotoxin A (BTX-A) injections to the forehead area result in wrinkle reduction and modifications of eyebrow position. DESIGN: Prospective study. SETTING: Private practice, Dermatologic Laser Centre, Marseille, France. SUBJECTS: Twenty-four adult patients treated with BTX-A (Vistabel) injections for forehead rhytides. INTERVENTION: Of the 24 patients, 12 received BTX-A injections of 5 U only and 12 received injections of 10 U into the forehead, with or without treatment of the lateral forehead. The eyebrow position, forehead height and number of forehead lines determine the number of injection points. Patients were evaluated before injection and every 2 months after treatment during next 8 months. RESULTS: In the two groups of 12 patients, we found no significant change between the two doses. At each time after injections (every 2 months until 8 months), both groups showed a statistically significant improvement except at 8 months. Both groups exhibited the same results on standardized photos and on 3D skin profilometry. CONCLUSIONS: The two doses of BTX-A injections into the forehead gave the same results. The duration of the effect is similar along 8 months. This study emphasizes the role of low doses of BTX-A injections to obtain good clinical results without freezing aspect.