[Endothelium protective effect of the high viscosity substances hyaluronic acid and methylcellulose in mechanical damage].

We investigated the protective effect of the high-viscosity substances sodium hyaluronate (1%) and methylcellulose (2%) on corneal endothelium in the face of severe mechanical insult. An intraocular lens was drawn across the endothelium of porcine corneas with standardized conditions. We used different compression forces. Methylcellulose and sodium hyaluronate were used as lubricating substances in the experimental groups, while balanced salt solution (BSS PLUS) was used in the control group. In this study no significant protective effect of high-viscosity substances against strong direct mechanical damage was generally demonstrable. Only one group in which a moderately strong compression force was applied showed significantly less smaller endothelial cell loss when methylcellulose was used. The most important function of viscous substances is therefore to prevent a collapse of the anterior chamber and to prevent any contact of the intraocular lens or of instruments with the endothelium. Any mechanical contact with the endothelium means an irreversible endothelial cell loss.