Abstract: Objective To evaluate the therapeutic efficacy of dexamethasone intravitreal implant(Ozurdex)in refractory macular edema secondary to acute retinal necrosis(ARN)guided by intraocular fluid detection. Methods One patient with refractory macular edema secondary to ARN was followed up, and the treatment regimen was precisely adjusted according to the intraocular fluid detection results in a prospective study. Results This study reports on a patient with refractory macular edema secondary to ARN who received precise treatment guided by the detection of intraocular fluid. The patient was admitted to hospital with acute progressive visual loss in the right eye for 4 d. Varicella herpes zoster virus(VZV)was detected in the intraocular fluid. The retinal inflammation resolved after administration of antiviral therapy, but there was secondary macular edema, which resolved after vitreous injection of Ranibizumab but was prone to recurrence. After 8 consecutive weeks of undetectable VZV in the intraocular fluid, Ozurdex was innovatively used to treat macular edema, which resolved completely after 3 consecutive intravitreal injections of Ozurdex and did not recur for 2 years. Conclusion This case suggests that detection of intraocular fluid can guide accurate diagnosis and treatment of ARN, and that refractory macular edema following viral clearance can be treated with Ozurdex, which has better long-term efficacy than Ranibizumab.

Key words: Acute retinal necrosis, Macular edema, Intraocular fluid detection, Dexamethasone intravitreal implant