Improving the staining characteristics of trypan blue in vitreo–retinal surgery

Abstract

Abstract: : Purpose:Trypan blue has been proposed as a non–toxic alternative to indocyanine green (ICG) for the staining of the internal limiting (ILM) and proliferative epiretinal membranes. Current practice requires an air–fluid exchange and provides a variable degree of membrane staining. This study was aimed at identifying simpler means of delivering trypan blue to the retinal surface while providing similar or better staining characteristics to those observed with an air–fluid exchange Methods:Trypan blue 0.4% in phosphated buffered saline was suspended in various dilutions of glucose solution from 2.5 to 5% and injected in enucleated porcine and human eyes to study the staining characteristics. The same was tried with methylcellulose containing trypan blue and diluted with varying concentrations of glucose solution Results:Both glucose and methylcellulose mixtures containing 5% glucose or more were denser than BSS+ and migrated onto the retinal surface. The glucose solution provided an intense staining of the ILM within several minutes of application. Methylcellulose was less effective at staining the membrane. Conclusions:Trypan blue can be delivered efficiently to the retinal surface without the need for an air–fluid exchange. Staining characteristics using this approach are sufficient to allow an efficient peeling of the membrane following an appropriate flush of the leftover dye

Keywords: proliferative vitreoretinopathy • macula/fovea • macular holes