Intravitreal Dexamethasone Implant for the Treatment of Postoperative Macular Edema

Abstract

Introduction: Macular edema after cataract surgery (Irvine-Gass syndrome) or pars plana vitrectomy is a postoperative complication which can lead to permanent visual loss. Increased inflammatory substances, such as prostaglandins and cytokines, are discussed to be causative. Currently, there are no evidence-based guidelines for the treatment of postoperative macular edema. Intravitreal dexamethasone (DEX) could be effective by its anti-inflammatory effect. We examined the functional and morphological results of treatment with 0.7 mg intravitreal DEX implant (Ozurdex®). Methods: In an observational study, we analyzed visual acuity (logMAR), intraocular pressure (IOP), clinical findings, and the central macular thickness (CMT, optical coherence tomography [OCT] Spectralis®, Heidelberg Engineering, 30° macular scan, 19 scans) of 12 eyes before and 1 month after the last DEX implantation (off-label use, Ozurdex®, Allergan, Inc., Irvine, CA, USA) for macular edema after cataract surgery or vitrectomy. Re-implantation was performed when OCT showed new intraretinal fluid along with a decrease in the patient's visual acuity. The mean follow-up was 14.4 ± 10.6 months. Results: Twelve eyes of 12 patients (4 female, 8 male) with a mean age of 62.6 ± 11.9 years were treated with a mean of 2.5 ± 1.6 intravitreal DEX implant injections. Prior to injection, the visual acuity was 0.74 ± 0.34 logMAR and the CMT was 608 ± 129 µm. One month after the last injection (after a mean of 437 ± 322 days), the CMT normalized (300 ± 90 µm, p < 0.01) in all cases with a visual acuity of 0.49 ± 0.43 logMAR (p < 0.01). After 8.1 ± 5.3 months, recurring macular edema could be completely reduced by re-injection in 66% (8 patients). Four patients had no recurrence. Postinjection, the mean IOP was 17.4 ± 6.8 mm Hg. Postinjection, 7 patients required topical antiglaucomatous therapy. Conclusions: Treatment with an intravitreal DEX implant is an effective therapy for postoperative macular edema. Each injection leads to a complete resorption of the edema with a significant increase in visual acuity.