Diffuse Unilateral Subacute Neuroretinitis: A Case Report Documenting Transretinal Migration of Nematodes.

Purpose: To report two cases of diffuse unilateral subacute neuroretinitis (DUSN) from northern Iran and to present the sequential imaging.

Methods: Two patients with large subretinal nematodes were evaluated and managed in our clinic. Serial fundus photography and optical coherence tomography (OCT) imaging were used to document the course of the disease. Laser photocoagulation was administered to manage the patients.

Results: The migration of the nematodes from subinternal limiting membrane space to subretinal space was documented in one case, coinciding with the onset of inflammatory and destructive processes. Both patients were successfully managed using laser photocoagulation alone. Follow-up examinations revealed partial recovery of the outer retinal layers and improvement in visual acuity. Nevertheless, some persistent atrophy in the retinal nerve fiber layer and ellipsoid layer was noted in the final examination.

Conclusions: We presented two cases of DUSN from northern Iran, with OCT documentation of transretinal migration in one case. Photocoagulation laser alone is an effective treatment modality in the early stage. The suboptimal final visual acuity appears to be linked to both inner and outer retinal layers' damage.