Published online June 16th, 2010 © http://www.ijav.org Case Report International Journal of Anatomical Variations (2010) 3: 84–85 Introduction The internal carotid artery is the larger terminal branch of common carotid artery. It originates at the level of upper border of the lamina of thyroid cartilage and ascends vertically in the carotid sheath and enters the carotid canal at the base of the skull. In the cranial cavity it passes through the cavernous sinus. After coming out of the cavernous sinus, it divides into anterior and middle cerebral arteries at the base of the brain. It is the major artery of the brain, eye and the internal ear. It has a straight course in the neck. Kink in its course in the neck may result in hindrance in the blood flow to the above regions and can cause serious problems. Case Report The study involved the dissection of the neck of an adult South Indian male cadaver aged approximately 50 years. The dissection was carried out at the Melaka Manipal Medical College (Manipal Campus). The dissection was carried out in the year 2008. The body was preserved in 10% formalin at a temperature of 4°C. During the dissection, we observed a loop formed by the internal carotid artery near the carotid bifurcation (Figures 1, 2). The artery on the left side of the neck was normal. An abnormal, enlarged lymph node was situated at the carotid bifurcation. This node was pushing into the loop of internal carotid artery (Figure 1). During the initial part of the dissection, the loop of the artery also looked like another lymph node. Careful dissection Satheesha NAYAK B. Department of Anatomy, Melaka Manipal Medical College (Manipal Campus) Manipal, INDIA. Satheesha Nayak B., MSc, PhD Professor of Anatomy Melaka Manipal Medical College (Manipal Campus) International Centre for Health Sciences Madhav Nagar, Manipal Udupi District, Karnataka State, 576 104, INDIA. +91 820 2922519 +91 820 2571905 nayaksathish@yahoo.com Received October 30th, 2009; accepted June 9th, 2010 ABSTRACT Knowledge of variations of internal carotid artery is important to surgeons doing head and neck surgery as well as to radiologists doing imaging and invasive techniques. In the current case, the right internal carotid artery showed a characteristic loop at its beginning. An abnormal, enlarged lymph node was found at the carotid bifurcation, which was projecting into the loop. The left internal carotid artery was normal. The unusual looping of internal carotid artery at its beginning might result in altered blood flow to the brain and may lead to confusions in surgical, imaging and invasive techniques. © IJAV. 2010; 3: 84–85. Key words [variation] [artery] [internal carotid artery] [deep cervical lymph node] eISSN 1308-4038 Unusual looping of the internal carotid artery in relation to an enlarged lymph node Figure 1. Dissection demonstrating the right side of the neck. (PBD: posterior belly of digastric; ECA: external carotid artery; SSG: submandibular salivary gland; ICA: internal carotid artery; CCA: common carotid artery; AC: ansa cervicalis; IJV: internal jugular vein; DCL: deep cervical lymph node; STA: superior thyroid artery) DCL ICA IJV AC CCA STA SSG ECA PBD