de Mendonça José Luiz Furtado, Viana Sergio Lopes, Freitas Flávia Mendes Oliveira, Matos Valter de Lima, Viana Maria Angélica de Carvalho Barbosa, Faria e Silva Renato, Quaglia Luiz Augusto Nardelli, Guerra Jozephina Gonçalves
Magnetic Resonance Department, Clínica Radiológica Vila Rica, Brasília, Brazil.
Can Assoc Radiol J. 2008 Apr;59(2):61-9.
Dysgenesis of the internal carotid artery (ICA) is a broad term comprising hypoplasia, aplasia and agenesis of the vessel. It is a rare anomaly, often clinically silent, that can be confidently diagnosed by means of noninvasive imaging methods.
After a review of teaching files, 7 patients with unilateral carotid dysgenesis were found, 2 with agenesis of the ICA, 3 with carotid aplasia, and 2 with hypoplasia of the vessel. Computed tomography (CT) and magnetic resonance angiography (MRA) of the brain were performed in all patients, with a complete magnetic resonance of the brain in 3 of them, a CT angiography of the brain in one, and MRA of the cervical arteries in 3.
The fetal pattern of arterial circulation was found in 3 patients with agenesis/aplasia of the ICA and the adult pattern was found in 2 patients, being the brain circulation of normal pattern in the patients with hypoplasia of the ICA. Two patients presented signs of reduced flow to the brain hemisphere ipsilateral to the carotid dysgenesis; one of them with an old homolateral brain infarction.
Far from being just an anatomic curiosity, the dysgenesis of the ICA may have serious consequences if not recognized prior to endarterectomies, carotid ligation or transsphenoidal surgery. As much as one-third of these patients will have intracranial aneurysms as well. The imaging methods, instead being mutually exclusive, are complementary in the evaluation of carotid dysgenesis.
颈内动脉发育异常是一个广义术语，包括该血管的发育不全、发育缺失和发育异常。它是一种罕见的异常情况，通常在临床上没有症状，可通过无创成像方法明确诊断。
查阅教学档案后，发现7例单侧颈动脉发育异常患者，其中2例颈内动脉发育缺失，3例颈动脉发育异常，2例血管发育不全。对所有患者均进行了脑部计算机断层扫描（CT）和磁共振血管造影（MRA），其中3例进行了全脑磁共振检查，1例进行了脑部CT血管造影，3例进行了颈部动脉MRA。
3例颈内动脉发育缺失/发育异常患者发现有胎儿期动脉循环模式，2例发现有成人期模式，颈内动脉发育不全患者的脑循环为正常模式。2例患者出现与颈动脉发育异常同侧脑半球血流减少的体征；其中1例有陈旧性同侧脑梗死。
颈内动脉发育异常远非只是一种解剖学上的奇特性，如果在动脉内膜切除术、颈动脉结扎术或经蝶窦手术前未被识别，可能会产生严重后果。这些患者中多达三分之一还会患有颅内动脉瘤。成像方法并非相互排斥，而是在评估颈动脉发育异常方面相互补充。
