Botulinum toxin A and facial lines: the variable concentration.

Our improved understanding of the functional anatomy of the face and of the action of the botulinum toxin A leads us to determine a new injection procedure which consequently decreases the risk of eyebrow and eyelid ptosis, and increases the toxin injection's possibilities and efficiencies. Variable toxin injection concentrations adapted to each injected area are used. Thanks to the new procedure in the upper face, toxin A action is quite close to an endoscopic surgical action. In addition, interesting results are achievable on the nose, upper part of the nasolabial fold, jawline and neck regions. Lastly, a smoothing effect on the skin is obtained by the anticholinergic action of the toxin A on the dermal receptors.