Contrasting short-interval behavior of two retinal emboli during spontaneous visual recovery in transient retinal ischemia: a multimodal imaging case report

Acute retinal ischemia may cause profound monocular visual loss. Visible retinal emboli can move, fragment, disappear, or remain stable, but spontaneous short-interval documentation of different behaviors among independently traceable emboli is uncommon. A 67-year-old man with a history of cigarette smoking and no known systemic or ocular disease presented approximately 4 hours after sudden, painless, severe visual loss in the left eye. Visual acuity was hand motion at 30 cm in the left eye and 20/20 in the right eye; intraocular pressure was 21 mmHg in both eyes. Initial color fundus photography showed two traceable refractile retinal arterial emboli, one in a superotemporal retinal arterial branch and another at the optic disc/peripapillary arterial segment. Initial macular optical coherence tomography showed preserved foveal architecture without conspicuous diffuse inner-retinal thickening or hyperreflectivity. During an approximately 30-minute interval before ophthalmic treatment, while the patient was undergoing emergency neurological evaluation, visual acuity improved spontaneously from hand-motion perception at 30 cm to counting fingers at the same distance. Repeat photography showed that the superotemporal embolus remained at the same arterial branch location, while the disc/peripapillary embolus had migrated into an inferior retinal arterial branch. Serial peripapillary optical coherence tomography provided supportive evidence of short-interval positional change of vascular-associated hyperreflective material corresponding to the migrating embolus. Post-improvement fluorescein angiography showed near-complete retinal vascular filling, consistent with reperfusion. Same-day brain magnetic resonance imaging showed no acute infarction. Cervicocephalic computed tomography angiography approximately 2 weeks later demonstrated mixed plaque with moderate stenosis at the ipsilateral internal carotid artery origin. Cardiology evaluation was recommended, but dedicated cardiac investigations were not completed. Papaverine was administered only after spontaneous improvement, so a treatment effect cannot be inferred. At 1 week, visual acuity had recovered to 20/20. This case documents contrasting short-interval behavior of two traceable retinal emboli during spontaneous recovery from transient retinal ischemia: one superotemporal branch embolus remained stationary, whereas a second disc/peripapillary embolus migrated into an inferior retinal arterial branch. The temporal association is descriptive and does not establish that embolus migration caused visual recovery. Rapid symptom resolution should not defer systemic vascular and cardiac evaluation.