Objective: To examine the efficacy of surgical removal of foveal hard exuda
tes in diabetic macular edema and to determine the expression of vascular e
ndothelial growth factor (VEGF) in the excised specimens.
Design: Cohort study.
Participants: Seven eyes of six patients with massive subfoveal hard exudat
e due to diabetic macular edema were examined. The average age of the patie
nt 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 com
plications were recorded; immunohistochemical staining for VEGF and other c
ell markers for macrophage and pigment epithelial cells in excised specimen
s 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, identi
fied by anticytokeratin and CD68 antibodies, was expressed in pigment epith
elial 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 th
e formation and persistence of foveal hard exudates in diabetic macular ede
ma.