Transitory ischemic attack associated with a rare fenestration of the cervical segment of the internal carotid artery: a case report

Fenestration of the cervical segment of the internal carotid artery is a very rare finding, and its origin is still not fully understood. Explanations of its genesis range from dissections leading to the fenestration to the more common interpretation as a developmental vascular variant. However, most reported cases were symptomatic and presented with dissections, where even endovascular treatment of the fenestration of the cervical segment of the internal carotid artery became necessary. Here we report a case of a fenestration of the cervical segment of the internal carotid artery suffering a transitory ischemic attack and local pain in absence of any sign of dissection. A 62-year-old Caucasian male patient was admitted to our institution because of an episode of amaurosis fugax, initially accompanied with headache. Magnetic resonance imaging revealed an intact fenestration of the cervical segment of the internal carotid artery on the symptomatic side. With antiplatelet therapy, all symptoms vanished within 2 months of the initial event. Our findings support the interpretation of a fenestration of the cervical segment of the internal carotid artery as a developmental vascular variant, but also suggest a substantial risk for dissection and ischemic stroke. Even in case of an accidental finding, clinicians should be aware of this. At least in this case, antiplatelet therapy seemed beneficial.