RESUMO
Correction of corneal astigmatism is a key element of cataract surgery, since post-surgical residual astigmatism can compromise the patient's uncorrected visual acuity. Toric intraocular lenses (IOLs) compensate for corneal astigmatism at the time of surgery, correcting ocular astigmatism. They are a predictable treatment. However, accurate measurement of corneal astigmatism is mandatory for choosing the correct toric IOL power and for planning optimal alignment. When calculating the power of toric IOLs, it is important to consider anterior and posterior corneal astigmatism, along with the surgically induced astigmatism. Accurate toric lens alignment along the calculated meridian is also crucial to achieve effective astigmatism correction. There are several techniques to guide IOL alignment, including the traditional manual marking technique and automated systems based on anatomic and topographic landmarks. The aim of this review is to provide an overview on astigmatism management with toric IOLs, including relevant patient selection criteria, corneal astigmatism measurement, toric IOL power calculation, toric IOL alignment, clinical outcomes and complications.
Assuntos
Astigmatismo/cirurgia , Implante de Lente Intraocular/métodos , Lentes Intraoculares , Humanos , Resultado do Tratamento , Acuidade VisualRESUMO
Correction of corneal astigmatism is a key element of cataract surgery, since post-surgical residual astigmatism can compromise the patient's uncorrected visual acuity. Toric intraocular lenses (IOLs) compensate for corneal astigmatism at the time of surgery, correcting ocular astigmatism. They are a predictable treatment. However, accurate measurement of corneal astigmatism is mandatory for choosing the correct toric IOL power and for planning optimal alignment. When calculating the power of toric IOLs, it is important to consider anterior and posterior corneal astigmatism, along with the surgically induced astigmatism. Accurate toric lens alignment along the calculated meridian is also crucial to achieve effective astigmatism correction. There are several techniques to guide IOL alignment, including the traditional manual marking technique and automated systems based on anatomic and topographic landmarks. The aim of this review is to provide an overview on astigmatism management with toric IOLs, including relevant patient selection criteria, corneal astigmatism measurement, toric IOL power calculation, toric IOL alignment, clinical outcomes and complications.
O tratamento do astigmatismo corneal é um fator importante na cirurgia de catarata, uma vez que o astigmatismo residual pode comprometer a acuidade visual não corrigida do paciente após a cirurgia. Lentes intraoculares (LIOs) tóricas compensam o astigmatismo corneal no momento da cirurgia, corrigindo o astigmatismo ocular. Ademais, constituem um tratamento previsível. Entretanto, é necessário obter uma medida precisa do astigmatismo corneal para selecionar o poder correto da LIO tórica e para planejar o melhor alinhamento da mesma. No cálculo do poder da LIO tórica, é importante considerar o astigmatismo das superfícies anterior e posterior da córnea, além do astigmatismo induzido na cirurgia. O alinhamento da lente tórica no meridiano planejado é essencial para se obter uma correção efetiva do astigmatismo. Há várias técnicas para guiar o alinhamento da LIO, incluindo a técnica de marcação manual tradicional e sistemas que se baseiam em pontos de referência anatômicos e topográficos. O objetivo desse artigo de revisão é discutir o uso de LIOs tóricas no tratamento de astigmatismo corneal, incluindo os critérios de seleção dos pacientes, a medida do astigmatismo corneal, o cálculo do poder da LIO tórica, o alinhamento da LIO tórica, os resultados clínicos e as complicações.