Multimodal Imaging Findings in Acute West Nile Virus Chorioretinitis.

PURPOSE To describe multimodal imaging findings of acute West Nile virus (WNV) chorioretinitis. METHODS Observational case report. Fundus photographs, fluorescein angiography, indocyanine green angiography, and swept-source optical coherence tomography angiography were used to characterize and describe the clinical findings. RESULTS A 58-year-old man presented with acute painless vision loss in the right eye.Multimodal imaging demonstrated multifocal pinpoint early phase hyperfluoresence with late expanding leakage on fluorescein angiography (FA) and late hyperfluorescence on indocyanine green angiography (ICGA). Swept-source optical coherence tomography angiography (SS-OCTA) en face imaging of the ellipsoid zone layer revealed target-like lesions with central hyperreflectivity with surrounding hyporeflectivity. At 4-week follow-up, the chorioretinal lesions now demonstrated greater demarcation of borders with increased pigmentation. At 8-week follow-up, fundus exam revealed multiple target-like lesions with hyperpigmentation centrally surrounded by a hypopigmented rim. Repeat FA demonstrated central hypofluorescence with surrounding hyperfluoresent staining rim prompting work-up for WNV, which was later confirmed by laboratory testing. The patient's visual acuity and clinical exam remained stable on subsequent follow-up visits. CONCLUSION Our case highlights multimodal imaging findings in the acute phase of WNV chorioretinitis which may be crucial to early diagnosis and identification.