Internal carotid artery anatomy – not always straightforward

Abstract

Objectives

To present a rare variant of internal carotid artery anatomy.

Methods

Case report presenting CT angiography finding of internal carotid anatomy variant.

Results

We present the case of an unusual origin of the occipital artery from cervical portion of the internal carotid artery as an incidental finding during CT angiography of the carotid arteries. In discussion, we discuss the possible embryological basis, incidence and prevalence of such finding and its possible clinical implications.

Conclusion

One of the specific aspects of carotid arteries is their straightforward anatomy – the cervical portion of internal carotid artery, unlike the external carotid, does not give origin to any branches – this aspect is even used as a highlight for orientation, e.g. during ultrasound examination. However, although rare, variants exist, and sometimes can have clinical importance – in the endovascular access or surgical treatment.