Clopidogrel effective for frequent transient monocular blindness caused by vulnerable plaque

Transient monocular blindness (TMB) is a well-known warning symptom of impending cerebral or retinal infarction, which suggests vulnerable ipsilateral carotid disease. Instability of free-floating thrombus may cause recurrent artery-to-artery embolism. A recent study showed that a combination of clopidogrel and aspirin might reduce microthromboembolisms. Here, we report a patient with frequent TMB despite aspirin monotherapy whose symptom disappeared after the addition of clopidogrel. This is the first report of aspirin-resistant frequent TMB caused by thromboembolism from vulnerable plaque that remitted after the addition of clopidogrel. These findings highlight the need for a randomized controlled trial to illustrate the most efficacious treatment strategy in this situation.