Angiogenesis in corneal diseases: Histopathologic evaluation of 254 human corneal buttons with neovascularization

Purpose. Angiogenesis in corneal diseases can necessitate corneal transplantation and induce graft rejection. The aim of this study was to find out the histopathologic prevalence of angiogenesis in human corneas removed during keratoplasty, to establish the histopathologic diagnoses most commonly associated with angiogenesis, and to evaluate the anatomic location of new corneal vessels. Methods. Corneal buttons (2,557) after keratoplasty were sent to and analyzed in our ophthalmopathology laboratory between 1992 and 1996. Of these, 1,278 full-thickness and lamellar corneal buttons were randomly retrieved and evaluated in this study. Results. Of 1,278 human corneal buttons obtained by keratoplasty, 254 (19.9%) showed angiogenesis. Associated histopathologic diagnoses were (a) scarring after keratitis (109, 45.4%); (b) graft rejection and insufficiency (73, 30.4%); (c) acute necrotizing ulcerative keratitis (30, 12.5%); and (d) scarring after mechanical or chemical injuries (28, 11.7%). Histopathologically, new vessels were usually associated with corneal edema or inflammatory cells or both (76%). The most common locations of new vessels were the upper and middle third of the corneal stroma. Only 11% of new vessels were located solely in the deep stromal layers. Conclusion. Angiogenesis is a common histopathologic feature of corneal diseases leading to corneal transplantation and was found in 19.9% of excised human corneal buttons. Systemic or topical antiangiogenic therapy could reduce the need for corneal transplantation and retransplantation.