Experimental encircling scleral buckle with silicone and hydrogel: histopathologic and comparative study of 26 rabbit eyes.

Abstract

To analyze histologic changes induced by encircling elements, rabbit eyes were implanted with two different biomaterials. Thirty-seven rabbit eyes (37 rabbits) were implanted with encircling oval episcleral elements. Two materials were used: silicone sponge and hydrogel. The animals were killed and their eyes collected for histopathology. Of 37 eyes, 26 that were implanted for 111 to 455 days were selected for the study. In 26 eyes, scleral buckling was visible. Scleral examination showed a regular erosion under the buckle, mainly with silicone. All explants were surrounded by a fibrous capsule, which was smooth and regular with silicone. With hydrogel, fragmentation was observed with a giant cell reaction. Capsule thickness increased, mainly with hydrogel. Fragmentation affected segmental or circumferential hydrogel explants. As in silicone explants, the capsule surface was normal when the hydrogel surface was respected. The fragmentation mechanism remains unclear.