Histopathologic retinal chances with intravitreous fluorosilicone oil in rabbit eyes

Background: Fluorosilicone oil (FSiO, 1,000-10,000 centistokes), which has a higher density (1.29 g/cm(3)) than vitreous gel, is useful as an operative tool and a tamponade for the inferior retina during difficult retinal detachment surgery. The occurrence of histopathologic retinal changes after injection of FSiO into the vitreous cavity is controversial. Methods: Retinas obtained from 18 rabbits were evaluated histopathologically within 8 weeks of injection into the vitreous cavity of purified FSiO or balanced salt solution as control in phakic eyes. The histopathologic retinal changes caused by FSiO were compared with those of previously reported high-density hydrophobic vitreous substitutes, such as silicone-fluorosilicone copolymer oil (SiFO) and perfluorocarbon liquids. Results: By light and electron microscopy, all retinas injected with FSiO were the same as control retinas within 2 weeks of the injection, but the outer plexiform layer disappeared from the inferior retina 4 weeks after injection. The receptor cell nuclei migrated to the photoreceptor layer in the inferior retina 8 weeks after injection, However, no preretinal membrane, including foam cells, was found in any eye injected with FSiO. Conclusion: FSiO may be useful as a temporary vitreous substitute in difficult inferior retinal detachments.