Update on botulinum toxin for facial aesthetics.

The use of botulinum toxin has revolutionized the treatment of facial lines with an incomparable safety record over the past 14 years. The most common used injection sites are shown in Fig. 9. With the recent FDA approval for Botox in the treatment of glabellar lines, its use will likely increase dramatically. It is essential that practitioners have a detailed and specific knowledge of the facial and neck musculature to be injected to minimize untoward side effects, especially in the early days of new users' learning curve. The specifics of the dilutions and units per amount used for the various different commercial forms of botulinum toxin types A and B need to be understood fully and standardized together with the potential for antigenicity with the higher protein load of type B. In addition, specific indications for the use of botulinum toxin as adjunctive therapy for specific facial surgical procedures (i.e., blepharoplasty, surgical brow lift, and laser resurfacing) will become better understood. [figure: see text] Finally, even though the anatomy of the facial musculature is well described, individual differences in men and women, in different population groups, and in tissue qualities, such as turgor and elasticity [87], are important factors to be considered before undertaking botulinum toxin injections. It is likely that the use of specific measuring devices, such as digital imaging, will further help define the use of botulinum toxin for different muscle groups and facial aesthetic indications.