New technique to demonstrate corneal magnification using trypan blue in cataract surgery

Abstract

RESUMOObjetivo: Demonstrar a magnificação corneana utilizando o azul de tripan na cirurgia de catarata. Métodos: Oito olhos de oito pacientes submetidos à facoemulsificação com implante de lente intraocular foram envolvidos neste estudo. Após corar a cápsula anterior do cristalino com azul de tripan 0,1% e realizar a capsulotomia circular contínua, a cápsula excisada foi colocada sobre a superfície corneana. Após observar e aferir a relação entre a borda da cápsula anterior excisada e a abertura da cápsula intracameral, o efeito da magnificação corneana foi claramente demonstrada e calculada através do método linear. Resultados: A média estimada da magnificação corneana foi de 20,88% com uma média de magnificação de área de 47,53%. Conclusão: A capsulorrexis corada pelo azul de tripan é útil na demonstração da magnificação corneana, auxiliando assim na correta confecção do seu tamanho.

Novel use of trypan blue in ocular surface staining: redefining implications for this vital dye

“…However, the study of TB dye for the ocular surface has been neglected since the original article by Norn in 1967 (6) . Trypan blue has many important applications in intraocular surgery and is very popular for facilitating capsulorrhexis (2,7) . Our research demonstrates that TB dye is also efficient at staining conjunctival and corneal surfaces in those with poor ocular surfaces.…”

Little pearls for routine cases

“…Years ago, we published an article showing that the corneal magnification is approximately 20%, which led to the design of a corneal marker. 1 After firming up the eye with an OVD and with the eye in the primary position to allow the Purkinje reflex to center the marker, gentle downward pressure leaves a circular imprint on the corneal surface, which can then be traced as the capsulorhexis is performed with either a needle or a forceps (Figure 2). I have no financial interest in this device, but I have a strong interest in sharing this useful technique.…”

Pearls for the young cataract surgeon: the pupil of concern

“…Dr. Thompson used this measurement to calculate the horizontal pupil size using a video recording, taking into consideration the corneal magnification of 20%, a number we had published in an earlier study. 10 This study allowed us to compare the actual pupil size in three different groups. When the pupil was 5 mm or less, a Malyugin ring was usually selected.…”