Monitoring Delayed Toxoplasmosis-Related Branch Retinal Artery Occlusion Using Widefield en face Optical Coherence Tomography and Multimodal Imaging

Ocular toxoplasmosis has a known, rare association with acute retinal artery occlusion (RAO). We describe a 21-year-old male who presented with acute focal toxoplasmosis chorioretinitis in the right eye treated with intravitreal clindamycin, intravitreal dexamethasone, and adjunct oral therapy for vision-threatening retinitis with subsequent quiescence. Nine months from his initial presentation, the patient presented with a branch RAO adjacent to an inactive retinal scar in the right eye. Widefield en face structural swept-source optical coherence tomography (SS-OCT) centered on the middle retina showed paracentral acute middle maculopathy (PAMM) in an arteriolar distribution. The patient was started on 81 mg of aspirin daily. Six months later, the en face structural SS-OCT and corresponding B-scans showed resolution of PAMM. Along with a review of the literature on toxoplasmosis-related RAOs, we present the first case of delayed-onset RAO in ocular toxoplasmosis.