Advanced Injection of Botulinum Toxin in the Nasal Muscles: A Novel Dynamic Change in Facial Expression.

[BACKGROUND] Among the nasal muscles, the levator labii superior alaeque nasi (LLSAN) acts as a transitional muscle that conjugates with other nasal and perinasal muscles. Thus, when treating the nasal region with Botulinum toxin (BTX), it is important to understand local nasal muscular dynamics and how they can influence the muscular dynamics of the entire face.

[METHODS] This is a retrospective analysis of cases treated by an injection pattern encompassing the face, including nasal muscles. Photographs were taken at rest and during motion (frontal and oblique views), before and after treatment.

[RESULTS] A total of 227 patients have been treated in the last 18 months with the following results: eyebrow tail lifting, softness of crow's feet, improvement of the drooping of the tip of the nose, and shortening of the lip philtrum when smiling. We present cases illustrating the use of this approach.

[CONCLUSIONS] Treating the facial muscles globally (including the frontal, corrugators, procerus, orbicularis oculi, platysma, DAO, and nasal muscles) can improve the smile and facial expressions. This is believed to occur because the elevated portion of the upper lip muscle becomes stronger as the nasal part of the LLSAN is paralyzed.

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