A Case of Unilateral Agenesis of Internal Carotid Artery with Throbbing Headache
Sung Kyu Na, MD Tai Hwan Park, MD, Jin Young Ahn, MD and Min Ky Kim, MD
Department of Neurology, Seoul Medical Center, Seoul, Korea
ABSTRACT
Background: Agenesis of internal carotid artery (ICA) has been known as an extremely rare congenital anomaly. Case Report: We report a patient with agenesis of the left ICA suffering from an ipsilateral throbbing headache just after taking an Over-The-Counter remedy for common cold. His left middle cerebral artery (MCA) originated from a basilar artery through a well developed posterior communicating artery. Most congenital anomalies of ICA do not cause circulatory insufficiency because of well developed collateral flow from the circle of Willis, communicating arteries from external carotid artery, and persistent embryologic arteries to the carotid artery territory. However, in this patient, hemodynamic evaluation performed by using transcranial Doppler sonography showed lower vasomotor reactivity of left MCA compared to that of right MCA. Conclusions: Agenesis of ICA can be presented with throbbing headache.