New surgical approach for removing massive foveal hard exudates in diabetic macular edema

Objective: To examine the efficacy of surgical removal of foveal hard exudates in diabetic macular edema and to determine the expression of vascular endothelial growth factor (VEGF) in the excised specimens. Design: Cohort study. Participants: Seven eyes of six patients with massive subfoveal hard exudate due to diabetic macular edema were examined. The average age of the patient was 56 years (range, 46-60 years). Intervention: Pars plana vitrectomy for removal of massive foveal exudates was performed. Main Outcome Measures: Preoperative and postoperative visual acuity and complications were recorded; immunohistochemical staining for VEGF and other cell markers for macrophage and pigment epithelial cells in excised specimens was performed. Results: Postoperative best-corrected visual acuity improved by two or more lines of Snellen equivalent in five eyes (71 %) (P = 0.0061). VEGF, identified by anticytokeratin and CD68 antibodies, was expressed in pigment epithelial cells and macrophages invading the hard exudates. Conclusion: Surgical removal of foveal hard exudates might be effective in low-vision patients with diabetic maculopathy. VEGF might play a role in the formation and persistence of foveal hard exudates in diabetic macular edema.