SURAMIN INHIBITS WOUND-HEALING FOLLOWING FILTERING PROCEDURES FOR GLAUCOMA

Background-Trabeculectomies are the most frequently performed procedur es in surgically treating eyes with glaucoma. Failures are caused by f ibrosis in the external ostium of the filtering procedure. In order to inhibit the fibrotic wound healing reaction, a new pharmacological ap proach using suramin, which inhibits a variety of important growth fac tors was used. Methods-Pigmented rabbits were used and filtering proce dures performed. Suramin was applied with concentrations ranging from 10 mg/ml to 333 mg/ml once during surgery and four times following sur gery. The success of the filtering procedure was assessed by intraocul ar pressure measurements. To evaluate possible intraocular toxic effec ts, treated eyes were histopathologically evaluated after 4 weeks, and the ciliary body adjacent to the site of application was examined usi ng electron microscopy. Results-With concentrations of suramin of 200 mg/ml and 333 mg/ml, the trabeculectomies were patent longer than in t he controls and in eyes operated with mitomycin C, which currently is the most frequently used antiproliferative drug to enhance the outcome of surgery in humans. No severe toxic effects to the ciliary epitheli um were seen in suramin treated eyes. Conclusions-This study demonstra tes for the first time the efficiency of a substance that broadly inhi bits the action of growth factors on target cells in the setting of oc ular wound healing. In this in vivo model, suramin has been shown to b e highly effective in preventing scarring and in having fewer toxic si de effects than usually used antimetabolites. These results therefore may suggest a new approach to the surgical treatment of glaucoma.