Amaurosis fugax associated with an internal carotid lesion is most likely to cause which effect?

Amaurosis fugax is characterized by transient vision loss, often described as a "curtain" coming down over the eye, and is typically caused by temporary disruption in blood flow, commonly due to embolic events. When associated with an internal carotid artery lesion, the most likely effect is temporary blindness of the ipsilateral eye, meaning the eye on the same side as the affected artery.

This occurs because the internal carotid artery supplies blood to the eye through the ophthalmic artery, which branches off from it. If there is an embolus or other occlusive event in the internal carotid artery, blood flow can be temporarily compromised, leading to vision loss in the eye supplied by that artery. The condition is transient, distinguishing it from more permanent forms of vision loss, which arise only in cases of more severe, uninterrupted ischemia or damage to the optic nerve or retina.

The correct choice accurately reflects the clinical presentations typically observed in cases of amaurosis fugax linked to internal carotid lesions, where the affected vision is temporary and confined to the eye on the same side as the vascular lesion.