Subtenon injection of natural leucocytic interferon‐α for treatment of diabetic macular edema

Abstract

AbstractPurpose To report the effect of subtenon injection of natural leucocytic interferon‐α (IFN‐α) on visual acuity (VA) and macular thickness (MT) in diabetic macular edema (DME).Methods 3 patients affected by diabetic macular edema refractory to intravitreal injection of bevacizumab received a complete ophthalmic examination including best‐corrected visual acuity (BCVA )and spectral domain ocular coherence tomography (SD‐OCT) before and after 1 week, 1 month and 4 months of a cycle of 3 parabulbar subtenonian injections in a week of IFN‐α (1x106 UL/ml, Alfaferone, AlfaWassermann).Results BCVA and MT significantly improved after a week in patient 2 (male, age 66): 20/50 vs 20/30 and 498μm vs 237μm. The result was stable during the third and fourth visits (299μm and 254 μm). BCVA and MT improved after a week in patient 1 (male, age 64): 20/40 vs 20/32 and 467μm vs 244μm, respectively; BCVA was stable during the follow up period, but MT increased significantly (610 μm and 603μm during the third and fourth visits). BCVA improved in patient 3 (female, age 75) after one week (20/50 vs 20/32) and was stable during the follow up period, but she had only a little improvement in MT (533μm, 483μm, 498μm and 493μm during the 4 visits).Conclusion BCVA improved in all the patients, and was stable after 4 months. MT greatly improved in two patients after 1 week but only in one patient was the result stable. IFN‐α, with its immunomodulatory, antiproliferative and antiangiogenic actions, was effective in improving VA and reducing macular thickness in DME. Randomized controlled studies will be useful to understand how long the effect of IFN‐α lasts, how many injections are needed and which patients might have the best results.