Misdiagnosis of an aberrant internal carotid artery (ICA) prior to biopsy, myringotomy, or other surgery can have disastrous and potentially life-threatening results. This is a relatively rare abnormality, with an incidence of less than 1%. There is agenesis of the first segment of the internal carotid artery with persistent compensatory enlargement of the inferior tympanic artery, which enters below through the inferior tympanic canaliculus and the caroticotympanic artery, which is the vestigial remnant of the hyoid artery arising from the ICA.
With an incidence of less than 0.5%, persistent stapedial arteries are less common than aberrant carotid arteries. Similarly, failure to identify this anomaly can result in dangerous hemorrhage into the middle ear.
The embryologic development of the branchial system produces six paired arches and corresponding arteries. The primitive second arch gives rise to the hyoid artery, which gives rise to the stapedial artery near its origin from the internal carotid artery.
When a stapedial artery persists in postnatal life, the middle meningeal artery arises from it. The foramen spinosum is absent. A persistent stapedial artery arises from the petrous ICA, entering the hypotympanum in an osseous canal. It goes upward between the crura of the stapes. Then, it enters the facial canal and extends a short distance, together with the facial nerve. Behind the geniculate ganglion, it leaves the facial canal, then travels anteriorly and cephalad in the extradural space of the middle cranial fossa.
在活检，鼓膜切开术或其他手术之前，误诊异位颈内动脉，可能会产生灾难性的和潜在威胁生命的后果。异位颈内动脉是比较罕见的异常，发病率不到1%。颈内动脉第一段的缺如而致鼓室下动脉持续代偿性扩张，进入走形于下鼓室小管和颈鼓动脉下方；是起源颈内动脉的舌动脉遗迹。
永存镫骨动脉的发病率小于0.5%，较异位的颈动脉少见。类似地，如不能识别这种异常会导致危险的大出血进入中耳。
鳃系统的胚胎发育产生六组成对的腮弓和相应的动脉。原始第二腮弓引起舌骨动脉，导致附近的镫骨动脉起源于颈内动脉。
当出生后，镫骨动脉持续存在，脑膜中动脉来自它。棘孔缺失。起自颈内动脉岩段的永存镫骨动脉，通过骨管进入鼓室；向上于镫骨脚之间。然后，进入面神经管内，伴随面神经延续一小段距离，在膝状神经节后面，离开面神经管，然后穿行于中颅窝硬膜外隙的前部。
