Duration of effectiveness of Botulinum toxin type A in excessive gingival display: a systematic review and meta-analysis

Abstract Botulinum toxin type A is effective in reducing excessive gingival display caused by hyperfunctional upper lip elevator muscles; however, this effect is transient. This study aimed to determine the duration of the effectiveness of botulinum toxin type A on a gummy smile. A systematic search was conducted using Medline (PubMed), Scopus, and Web of Science electronic databases, from 1970 to March 2017 with no language restriction; the search included studies evaluating adult patients with excessive gingival display who were treated with botulinum toxin and were followed-up for at least 3 months. OpenGrey and Clinical Trial Registry were also consulted. Quality assessment was applied to determine the level of evidence and bias, and a meta-analysis was performed. Of 2181 full texts, 71 were obtained, with 3 prospective studies meeting the selection criteria. The gingival display was significantly reduced to baseline with 2, 4, and 8 weeks of treatment. The gingival display considerably reduced at the baseline-2-week comparison (-4.44 mm using raw data and-4.05 mm using the standard difference) and increased throughout the weeks of follow-up. There is scant evidence to determine the duration of the effectiveness of toxin type A on a gummy smile. The effect tends to be stable until at least 8 weeks of follow-up, and the gingival exposure may not return to baseline within 12 weeks of follow-up. Well-designed randomized clinical trials with a minimum of 6 months of follow-up are necessary to strengthen the evidence.

Botulinum toxin for treating unilateral apraxia of eyelid opening in a patient with congenital myotonia / Tratamento da apraxia de abertura palpebral unilateral em portador de miotonia congênita com botulinum toxin

ABSTRACT A 37-year-old female presented with severe apraxia of lid opening (ALO) affecting the right upper lid associated with Becker congenital myotonia (MC). The patient had a history of right upper lid ptosis for 25 years that was exacerbated over the previous month with severe incapacity to open her right eye. No other associated neurological or ophthalmic symptoms were observed. The patient was treated with botulinum toxin (BoNT-A) injection into the pretarsal and lateral canthus region of the orbicularis oculi of the affected eyelid. Treatment with BoNT-A is an effective method of managing ALO in Becker MC. This is the first case of unilateral ALO in the course of Becker MC that was successfully treated with injections of botulinum toxin.

RESUMO Trata-se de uma mulher de 37 anos apresentando grave apraxia de abertura da pálpebra (AAP) superior direita associada com miotomia congênita de Becker (MC). A paciente há 25 anos apresentava ptose palpebral a direita e há um mês desenvolveu incapacidade de abertura do olho direito. Não havia associação com outro sintoma neurológico ou oftalmológico. A paciente recebeu injeção de botulinum toxin (BoNT-A) no músculo orbicular a direita, na região pretarsal e no canto lateral. A BoNT-A foi efetiva para o tratamento da AAP associada com miotomia congênita de Becker.

Keratoconus progression is not inhibited by reducing eyelid muscular force with botulinum toxin A treatment: a randomized trial / A progressão do ceratocone não é inibida reduzindo a força palpebral com o uso da toxina botulínica tipo A: ensaio clínico randomizado

ABSTRACT Purpose: To evaluate whether reducing eyelid muscular force through the administration of botulinum toxin type A (BTX-A) to the orbicularis oculi muscles of patients with keratoconus affected corneal parameters indicative of disease progression. Methods: In this prospective parallel randomized clinical trial, 40 eyes of 40 patients with keratoconus were randomized into equally sized control and BTX-A groups. Patients in the BTX-A group received subcutaneous BTX-A injections into the orbicularis muscle. The control group received no intervention. Palpebral fissure height, best spectacle-corrected visual acuity (BSCVA), and corneal topographic parameters were evaluated at baseline and at 3-, 6-, 12-, and 18-month follow-ups. Results: The mean ± standard deviation vertical palpebral fissure heights were 9.74 ± 1.87 mm and 9.45 ± 1.47 mm at baseline in the control and BTX-A groups, respectively, and 10.0 ± 1.49 mm and 9.62 ± 1.73 mm at 18 months, with no significant difference between the groups (p=0.337). BSCVA values were 0.63 ± 0.56 and 0.60 ± 0.27 at baseline in the control and BTX-A groups (p=0.643), and 0.52 ± 0.59 and 0.45 ± 0.26 at 18 months, again with no significant difference between the groups (p=0.452). In addition, there were no statistical differences between the groups at 18 months for the three keratometry topographic parameters: flattest (K1), steepest (K2), and mean (Km) keratometry (p=0.562). Conclusion: BTX-A inhibition of eyelid force generation did not result in detectable changes in corneal parameters in keratoconic patients during 18 months of follow-up.

RESUMO Objetivo: Avaliar se a administração da toxina botulínica tipo A (BTX-A) no músculo orbicular de pacientes com ceratocone a fim de reduzir a força muscular palpebral pode alterar os parâmetros corneanos indicativos de progressão da doença. Métodos: Ensaio clínico randomizado paralelo prospectivo. Quarenta olhos de 40 pacientes, randomizados em grupo controle ou grupo BTX-A na razão de 1:1. Pacientes do grupo BTX-A foram submetidos à injeção subcutânea da toxina botulínica tipo A no músculo orbicular. Os pacientes do grupo controle não sofreram nenhuma intervenção. Foram avaliados a medida da fenda palpebral, melhor acuidade visual corrigida, e topografia corneana nos momentos pré-operatório, e aos 3-,6-,12-, e 18 meses de seguimento. Resultados: Média ± DP (desvio padrão) da fenda palpebral no pré-operatório nos grupos controle e BTX-A foram 9,74 ± 187 e 9,45 ± 1,47 mm, respectivamente; aos 18 meses, a média da altura da fenda palpebral vertical nos grupos controle e BTX-A foram 10,0 ± 1,49 mm e 9,62 ± 1,73 mm, respectivamente, sem diferença significante entre os grupos (p=0,337). A média pré-operatória da melhor acuidade visual corrigida nos grupos controle e BTX-A foram 0,63 ± 0,56 e 0,60 ± 0,27, respectivamente (p=0,643); aos 18 meses, a média nos grupos controle e BTX-A foram 0,52 ± 0,59 e 0,45 ± 0,26, respectivamente, sem diferença significante entre os grupos (p=0,452). Não houve diferença estatística entre os grupos aos 18 meses para todos os parâmetros topográficos ceratométricos avaliados, mais plano-(K1), mais curvo-(K2), e ceratometria média Km (p≥0,562). Conclusão: A inibição da força muscular palpebral pela toxina botulínica tipo A não causou alterações detectáveis nos parâmetros corneanos em pacientes com ceratocone, com 18 meses de seguimento.

Combined treatment with botulinum toxin and hyaluronic acid to correct unsightly lateral-chin depression* / Tratamento combinado com toxina botulínica e ácido hialurônico para correção da depressão inestética lateral mentoniana

With aging, anatomical changes are observed in the face. In the lower third, these changes are expressed as ptosis of the angle of the mouth, lip enhancement groove mentalis; decrease in concavity between the jaw and neck and very noticeable platysmal banding. The repeated contraction of muscles of the lateral-chin together with the band platysmal side form what are called a marionette groove. Treating the whole lateral-chin area can result in a more harmonious aspect of the face when compared with treatment of a marionette groove in isolation. In this paper we describe combined treatment of the lateral chin area using botulinum toxin and fillers.

Com o envelhecimento observamos mudanças anatômicas na face. No terço inferior essas mudanças se expressam como ptose do ângulo da boca; acentuação do sulco lábio mentoniano; diminuição da concavidade entre a mandíbula e o pescoço e formação de bandas platismais bem evidentes. A contração repetida dos músculos da região latero-mentoniana juntamente com a banda platismal lateral, forma o que chamamos de sulco de marionette. Ao tratarmos toda região latero-mentoniana conseguimos um resultado mais harmônico, quando comparado com o tratamento isolado do sulco de marionette. Nesse artigo apresentamos o tratamento combinado da região latero mentoniana com o uso de toxina botulínica e preenchedores.

Crotoxin in humans: analysis of the effects on extraocular and facial muscles / Crotoxina em humanos: estudo da ação em músculos extraoculares e faciais

PURPOSE: Crotoxin is the main neurotoxin of South American rattlesnake Crotalus durissus terrificus. The neurotoxic action is characterized by a presynaptic blockade. The purpose of this research is to assess the ability of crotoxin to induce temporary paralysis of extraocular and facial muscles in humans. METHODS: Doses of crotoxin used ranged from 2 to 5 units (U), each unit corresponding to one LD50. We first applied 2U of crotoxin in one of the extraocular muscles of 3 amaurotic individuals to be submitted to ocular evisceration. In the second stage, we applied crotoxin in 12 extraocular muscles of 9 patients with strabismic amblyopia. In the last stage, crotoxin was used in the treatment of blepharospasm in another 3 patients. RESULTS: No patient showed any systemic side effect or change in vision or any eye structure problem after the procedure. The only local side effects observed were slight conjunctival hyperemia, which recovered spontaneously. In 2 patients there was no change in ocular deviation after 2U crotoxin application. Limitation of the muscle action was observed in 8 of the 12 applications. The change in ocular deviation after application of 2U of crotoxin (9 injections) was in average 15.7 prism diopters (PD). When the dose was 4U (2 applications) the change was in average 37.5 PD and a single application of 5U produced a change of 16 PD in ocular deviation. This effect lasted from 1 to 3 months. Two of the 3 patients with blepharospasm had the hemifacial spasm improved with crotoxin, which returned after 2 months. CONCLUSIONS: This study provides data suggesting that crotoxin may be a useful new therapeutic option for the treatment of strabismus and blepharospasm. We expect that with further studies crotoxin could be an option for many other medical areas.

OBJETIVO: A crotoxina é a principal neurotoxina da cascavel sul-americana Crotalus durissus terrificus e sua ação neurotóxica caracteriza-se por um bloqueio pré-sináptico. O objetivo da pesquisa é avaliar a capacidade da crotoxina em induzir paralisia transitória de músculos extraoculares e faciais em seres humanos. MÉTODOS: As doses utilizadas de crotoxina foram de 2 a 5 unidades (U), sendo que cada unidade correspondia a uma DL-50. Na primeira etapa, aplicou-se 2U de crotoxina em músculos extraoculares de 3 indivíduos amauróticos, candidatos à evisceração. Na segunda etapa, realizaram-se 12 aplicações de crotoxina em músculos extraoculares de 9 indivíduos estrábicos e amblíopes. Na terceira e última etapa, utilizou-se a crotoxina para o tratamento do blefaroespasmo essencial em 3 indivíduos. RESULTADOS: Nenhum paciente demonstrou qualquer efeito sistêmico ou alteração da visão ou de qualquer estrutura ocular. O único efeito local adverso foi hiperemia conjuntival, que melhorou espontaneamente. Em 2 pacientes não houve alteração do desvio ocular após a aplicação de 2U de crotoxina. Observou-se em 8 das 12 aplicações, limitação do movimento ocular no campo de ação do músculo aplicado. A diminuição do desvio ocular com 2U crotoxina (9 aplicações) foi em média de 15,7 dioptrias prismáticas (DP); na dosagem de 4U (2 aplicações) foi em média de 37,5 DP e na única aplicação de 5U, obteve-se redução de 16 DP no desvio ocular. A alteração do alinhamento ocular manteve-se por 1 a 3 meses. Dois dos 3 pacientes portadores de blefaroespasmo apresentaram melhora dos espasmos hemifacias, os quais voltaram após 2 meses. CONCLUSÕES: Através dos resultados observados neste estudo, acreditamos que a crotoxina possa ser útil no tratamento do estrabismo e do blefaroespasmo. Novos estudos precisam ser realizados para confirmar a eficácia e a segurança da crotoxina como opção terapêutica para diversas áreas da medicina que atualmente utilizam a toxina botulínica.

The role of botulinum toxin in correcting frontalis-induced eyelid pseudo-retraction post ptosis surgery.

We report a case of a 52-year-old female patient who developed overcorrection, due to brow overuse, post surgery for bilateral aponeurotic ptosis. The patient had undergone levator palpebrae superioris plication bilaterally. Due to brow overuse habituated by long standing ptosis, the patient presented with superior scleral show, post ptosis surgery. The lid contour was normal in both eyes and when brow overaction was blocked mechanically, the palpebral fissure heights were normal, comparable, with no scleral show bilaterally. Despite repeated instructions, when the patient continued brow overuse subconsciously, an injection of botulinum toxin was given just above both brows. This led to elimination of brow overuse within a month, with elimination of superior scleral show. The patient maintained lid and brow symmetry with no overaction, eight months post injection.