[Efficacy of intravitreal dexamethasone implants in macular edema excluding venous occlusions: results for a cohort of 80 patients]

Abstract

Introduction: The intravitreal dexamethasone implant has shown efficacy in the treatment of macular edema (ME) arising after retinal venous occlusions (central or branch), and in the treatment of non-infectious uveitis. The purpose of this study was to evaluate the efficacy of this implant in the treatment of other diffuse macular edemas with an inflammatory mechanism.

Materials and methods: We carried out a retrospective cohort study over 2 years: from January 2012 to December 2013, including all patients who received at least one injection of intravitreal dexamethasone implant, excluding venous occlusions and non-infectious uveitis. The primary study parameter was the progression of visual acuity. The study protocol had the approval of the institutional review board of the respective clinical ethics committees, and was conducted in accordance to the tenets of the Declaration of Helsinki.

Results: Eighty patients were included. Eighty-eight percent of patients were pseudophakic. The indications for treatment were: diabetic ME when anti-VEGF were ineffective (53%), ME after retinal detachment (RD) (22%), ME of Irvine-Gass syndrome (16%), ME after endophthalmitis (4%), macular telangiectasia (4%), ME secondary to retinitis pigmentosa (1%). The mean ETDRS visual acuity was 53.7 letters prior to injection, improving to 62.3 letters after injection (P<0.001). The average gain in visual acuity was 6.7 letters [4.53;8.84] (P<0.001) in patients treated for diabetic ME, 9.6 letters [6.1;13.1] (P<0.001) in patients with ME after RD, and 15.2 letters [10.25;20.28] (P<0.001) for Irvine-Gass syndrome. The mean duration of efficiency was 4.6 months, with a median of 3.8 months.

Conclusion: The intravitreal dexamethasone implant appears to be an effective second-line treatment even in patients with diabetic ME after failure or in the case of contraindication of anti-VEGF. It is also effective and well tolerated in patients with ME after RD, as well as in patients with Irvine-Gass syndrome.

Keywords: Diabetes; Diabète; Décollement de rétine; Endophtalmie; Endophthalmitis; Implant intravitréen de dexaméthasone; Intravitreal dexamethasone implant; Irvine-Gass syndrome; Macular edema; Macular telangiectasia; Retinal detachment; Retinitis pigmentosa; Rétinopathie pigmentaire; Syndrome d’Irvine-Gass; Télangiectasies maculaires; Œdème maculaire.