OCT-Angiography Findings in Acute Diffuse Unilateral Subacute Neurorretinitis: A Case Report

Purpose: To report multimodal imaging findings in acute Diffuse Unilateral Subacute Neuroretinitis (DUSN), emphasizing the potential role of choriocapillaris OCT-angiography (OCT-A) as a biomarker of inflammatory activity and its relationship with visual outcomes.Methods: We describe the case of a previously healthy 36-year-old male with acute DUSN who presented with progressive, painless visual loss in the right eye. Clinical examination and multimodal imaging, including OCT-A and indocyanine green angiography, were performed before and after treatment with oral albendazole and systemic corticosteroids.Results: Initial examination under systemic corticosteroid therapy was unremarkable. After corticosteroid tapering, visual acuity declined to 20/160, with the appearance of deep multifocal lesions in the posterior pole consistent with acute DUSN. Multimodal imaging demonstrated early choroidal inflammatory involvement, with multiple no-flow areas in the choriocapillaris on OCT-A showing exact topographic correlation with hypofluorescent spots on indocyanine green angiography. Treatment resulted in partial choriocapillaris reperfusion, regression of inflammatory lesions, and improvement of visual acuity to 20/50. However, ganglion cell complex thickness maps obtained after inflammatory resolution revealed severe, persistent thinning, indicating irreversible neuronal damage.Conclusions: Choriocapillaris OCT-A may serve as a useful biomarker of inflammatory activity in acute DUSN. This case also highlights that visual prognosis depends critically on prompt diagnosis and early treatment to limit irreversible retinal neuronal damage.