BILATERAL ABSENCE OF COMMON CAROTID ARTERY WITH VARIANT BRANCHING PATTERN OF AORTIC ARCH

Background: Variation in the branching pattern of aortic arch occurs as a result of developmental changes involved in the transformation of the embryonic pharyngeal arch system of arteries into the adult arterial pattern. Materials and Method: During routine dissection for first MBBS in the department of Anatomy BMCRI, Bangalore, it was observed that both the common carotid arteries were absent in a 45 year old male. Result. Both external carotid arteries originated from the right brachiocephalic trunk. (Innominate artery).The right internal carotid artery originated from the distal part of right brachiocephalic trunk and left internal carotid artery from the aortic arch along with the left vertebral artery. The study reports the division of brachiocephalic artery into right and left external carotid artery, right internal carotid artery and right subclavian artery. Discussion: The variation occurs as a result of increased absorption of third and fourth aortic arches into the aortic sac. Conclusion: These kind of variations should be well known by the surgeons before attempting any surgeries or during four vessel angiography.