Occipital artery arising from the internal carotid artery: a case report.

Variations of the branches of the external carotid artery have been well documented in the available literature. However, variation of the occipital artery arising from the internal carotid artery is extremely rare case. A 42-year-old man patient who suffered from subarachnoid hemorrhage with suspicious vascular anomalies was found to have this variation on the right side by angiography during selective catheterisation of main carotid artery for vascular mapping. Our literature searches revealed that there was rare case such variations. We think that this variation should contribute to literature and should be kept in mind during surgical, radiological and diagnostic procedures.