Indian Journal of Vascular and Endovascular Surgery

: 2017  |  Volume : 4  |  Issue : 3  |  Page : 127--128

Anatomical Variant: Ascending Pharyngeal Artery Arising from the Extracranial Internal Carotid Artery

Chinnam Naidu Sirasapalli, T Mandapal, Subhendu Parida, Murali Belman 
 Department of Radiology, Care Institute of Medical Sciences, Hyderabad, Telangana, India

Correspondence Address:
Chinnam Naidu Sirasapalli
Department of Radiology, Care Institute of Medical Sciences, Hyderabad, Telangana


Ascending pharyngeal artery (APA) is a branch of the external carotid artery. Extracranial internal carotid artery (ICA) usually does not have any branches. We present here a rare case of anomalous origin of the APA from the extracranial ICA and discuss the clinical importance of this rare anatomical variant.

How to cite this article:
Sirasapalli CN, Mandapal T, Parida S, Belman M. Anatomical Variant: Ascending Pharyngeal Artery Arising from the Extracranial Internal Carotid Artery.Indian J Vasc Endovasc Surg 2017;4:127-128

How to cite this URL:
Sirasapalli CN, Mandapal T, Parida S, Belman M. Anatomical Variant: Ascending Pharyngeal Artery Arising from the Extracranial Internal Carotid Artery. Indian J Vasc Endovasc Surg [serial online] 2017 [cited 2020 Oct 21 ];4:127-128
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Full Text


Branches arising from the extracranial internal carotid artery (ICA) are very rare. They are usually discovered incidentally during angiography, color-flow duplex scan, postmortem examination, or anatomic dissection.[1],[2] Ascending pharyngeal artery (APA) is the smallest branch of external carotid artery (ECA) arising from its posterior wall.[3] There are reports describing the anomalous origin of ECA branches from ICA.[1] APA originating from cervical ICA is the most common variant and is seen in 2% of specimens during the surgical autopsy.[1],[3]

 Case Report

A 70-year-old man came for a general health checkup to our institute. He was a known hypertensive on regular medication. On carotid Doppler examination, there were calcified plaques in both carotid bulbs extending into proximal ICAs causing more than 50% diameter stenosis. Hence, he was advised for a computed tomography (CT) cerebral angiogram for further evaluation.

CT cerebral angiography of the neck and brain was done in a Dual Source 64 Slice CT scan (Siemens SOMATOM Definition) using 80 ml of nonionic iodinated contrast (iohexol), 120 KV, and 133 mAs. Volume-rendered technique images [Figure 1]a and [Figure 1]b were obtained which clearly depict right APA arising from the anteromedial wall of proximal right ICA, just 4 mm from its origin at the level of C3 vertebra.{Figure 1}

Aorta starts developing during the 3rd week of gestation.[4] Each primitive aorta consists of a dorsal and a ventral segment that are in continuation with the first aortic arch.[4] Six paired aortic arches develop between the ventral and dorsal aortae.[4] Maxillary artery and portions of external carotids develop from the first pair, whereas the common carotids and portions of the internal carotids develop from the third arch.[5] Stapedial arteries arise from the second pair.[4] Variants arise when the first and second arch remnants are connected directly by the vascular buds to the internal carotid instead of external carotid.[5] Any branch of ECA can arise from the cervical segment of ICA.[5] Of all the branches, APA arising from the extracranial ICA is the most commonly encountered variant after occipital artery.[5],[6] Frequency of occurrence of these anomalous origins is summarized in [Table 1].[6]{Table 1}

It is important to consider these branches from the ICA in the diagnosis as well as surgical treatment of carotid occlusive disease.[5] A completely occluded ICA is a contraindication for carotid endarterectomy, but the patients with variants receive blood from these branches preventing complete occlusion of ICA.[5] Flow from the variant branches limits the length of the occlusion, thus making the carotid endarterectomy feasible.[2] Back bleeding from these branches is problematic during carotid endarterectomy, which is the most common complication from these anomalous branches.[5] APA arising from the origin of ICA and coursing parallel to ICA can mimic double lumen seen in ICA dissection.[3]

Hence, knowledge about this variant helps in evading misdiagnosis as well as in preventing complications during carotid endarterectomy.

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Conflicts of interest

There are no conflicts of interest.


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