Central retinal artery occlusion and subsequent amaurosis fugax in the contralateral eye associated with the G20210A prothrombin gene (F2) variant: a case report

PURPOSE: Report the case of a patient with a history of central retinal artery occlusion in her right eye and amaurosis fugax associated with acute ischemic changes in her left eye related to a prothrombin G20210A gene variant, in which OCT-A was used as a diagnostic and therapeutic tool. CASE PRESENTATION: 55-year-old woman with a history of central retinal artery occlusion in her right eye and prothrombin gene G20210A (F2) variant diagnosis. She presented to our consultation with amaurosis fugax in her left eye. As medical history, she had an episode of bilateral posterior scleritis diagnosed asynchronously with the current episode. Vascular, autoimmune, and metabolic prothrombotic diseases were ruled out. OCT-A showed areas suggesting acute ischemia consistent with macular retinopathy in her left eye. Anticoagulant therapy with Apixaban was initiated, considering the risk for her vision. Control OCT-A showed perfusion improvement in the previous site of the occlusive vascular event. We also considered the extent of the inflammatory response due to posterior scleritis as a differential diagnosis. Nevertheless, it is less likely, considering the temporality between scleritis and the retinal-vascular episodes. CONCLUSIONS: While the G20210A prothrombin gene (F2) variant is a rare cause of retinal artery occlusion, it is important to consider it a differential diagnosis. Good visual outcomes can be achieved with prompt initiation of antithrombotic treatment. In addition, OCT-A is useful for diagnosing ischemic retinal changes that cannot be observed with other diagnostic methods and monitoring them.