VISCOELASTIC ADHERENCE TO CORNEAL ENDOTHELIUM FOLLOWING PHACOEMULSIFICATION

Purpose: To compare the residual adherence of viscoelastics to the cor neal endothelium following phacoemulsification in an in vitro rabbit m odel. Setting: Departments of Ophthalmology and Anatomy, Wayne State U niversity, Detroit, Michigan, USA. Methods: Three groups of 10 rabbit eyes each had a lensectomy via phacoemulsification using sodium hyalur onate (Amvisc Plus(R), Healon GV(R)) or sodium chondroitin sulfate-sod ium hyaluronate (Visoat(R)) as the viscoelastic agent. Alter phacoemul sification and cortex removal, a central corneal block was excised, cr yofixed, and processed for light and electron microscopy. Viscoelastic thickness was determined by a calibrated reticule on the light micros cope or a calibrated measuring program in the electron microscope. The nonparametric statistical test, Kruskal-Wallis, was used to compare v iscoelastic groups. Results: Median phacoemulsification time between v iscoelastic agents was not significantly different. Median viscoelasti c thicknesses were 13.0 mu m for Amvisc Plus, 0.4 mu m for Healon GV, and 375.0 mu m for Viscoat, Each was significantly different from the others (Kruskal-Wallis, P < .001). Conclusions: Median thickness of Am visc Plus, Healon GV, and Viscoat remaining adherent to the corneal en dothelium after phacoemulsification as markedly different. Viscoat pro vided the greatest amount of viscoelastic material adjacent to the cor neal endothelium.