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Glabellar contraction patterns: a tool to optimize botulinum toxin treatment

de Almeida AR, da Costa Marques ER, Banegas R, Kadunc BV

Dermatologic surgery : official publication for American Society for Dermatologic Surgery [et al.], 2012

334 participants

Abstract

BACKGROUND: Botulinum toxin is a well-established treatment for dynamic glabellar lines. A previous study evaluated the existence of glabellar contraction "patterns," according to the predominance of eyebrow approximation, depression, or elevation movements, namely "U," "V," "convergent arrows," "omega," and "inverted omega."

OBJECTIVES: To confirm contraction patterns in the adult population for a better treatment approach and to verify whether changes occur after repeated treatment.

METHODS: Pairs of photographs-at rest and under contraction-from two groups were retrospectively analyzed: 334 adult volunteers with a predominance of specific movements, being verified and 36 previously treated individuals when they returned for re-injections.

RESULTS: The five glabellar contraction patterns were confirmed. Each individual's initial pattern reappeared upon waning of the toxin effect.

CONCLUSION: Interpersonal differences in facial animation are observed. Classifying glabellar wrinkles allows accurate treatment with botulinum toxin, injecting the most commonly recruited muscles with higher doses or into more sites. Muscles not so recruited are spared or injected with lower doses for more-effective and -natural results. Although botulinum toxin blockade causes recruitment of adjacent muscles, the initial muscle contraction pattern is resumed when the effect wanes.

How strong is the evidence?

Evidence Hub reads this as a cohort study, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence. Reported size: 334 participants or records.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

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