The effects of the intraocular dye brilliant blue G (BBG) mixed with varying concentrations of glucose on retinal function in an isolated perfused vertebrate retina

Abstract

During vitreoretinal surgery, vital dyes such as brilliant blue G (BBG) are used to visualize anatomical structures. By adding glucose to a concentration of 5%, many surgeons try to achieve a dye mixture heavier than water to facilitate staining of the ILM without preceding fluid-air exchange. However, the intraocular use of high glucose concentrations is critical. This study investigated the effect of 0.4 ml BBG (Brilliant Peel™ 0.25 mg/ml, Fluoron, Ulm, Germany) mixed with various glucose concentrations on the retina in an pseudo in vivo model Bovine retinas were isolated and superfused with an oxygen saturated nutrient solution, and the electroretinogram (ERG) was recorded. BBG mixed with 0.05 ml/0.1 ml/0.15 ml glucose 40% was applied epiretinally. ERG recovery was monitored for 75 minutes. 1 mM aspartate was added to the nutrient solution to obtain a-waves. After application of BBG/0.05 ml 40% glucose, a non-significant decrease of the b-wave amplitude was recorded (11.2%). In contrast, higher glucose concentrations showed a significant decrease of the b-wave (23.40% at 0.1 ml glucose, 26% at 0.15 ml glucose). The a-wave amplitudes showed no significant change at the end of the washout for all concentrations. The clinically used mixture of BBG and glucose seems to be safe up to a concentration of 5%. However, higher concentrations of glucose starting from 10% showed strong evidence of a toxic effect on the retinal function and should be avoided.