TY - JOUR T1 - Congenital Absence of the Internal Carotid Artery: Case Reports and Review of the Collateral Circulation JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 1953 LP - 1959 VL - 22 IS - 10 AU - Curtis A. Given II AU - Frank Huang-Hellinger AU - Michael D. Baker AU - Neeraj B. Chepuri AU - P. Pearse Morris Y1 - 2001/11/01 UR - http://www.ajnr.org/content/22/10/1953.abstract N2 - Summary: Absence of the internal carotid artery (ICA) is a rare congenital anomaly. The embryology of the ICA and the common collateral pathways associated with its congenital absence are reviewed, with four new cases provided for illustration. While collateral blood flow may allow these patients to remain asymptomatic, two of our patients presented with transient ischemic attacks. Recognition of this anomaly has important implications during planned carotid or transsphenoidal surgery, in thromboembolic disease, and in the surveillance and detection of associated cerebral aneurysms. ER -