Figure 1

Posterior view of sharp kinking* "extracranial siphon" of the highest portion of the cervical part of the left internal carotid artery (ICA) on coronal cross section (upright position). 1 – cervical part of ICA; 2 – petrous part of ICA; 3 – external carotid artery; 4 – superior thyroid artery; 5 – ascending pharyngeal artery; 6 – occipital artery; 7 – pharyngeal venous plexus; 8 – accessory nerve (elevated); 9 – vagus nerve (shifted to the right and upward); 10 – superior laryngeal nerve; 11 – superior cervical sympathetic ganglion (SCSG) (shifted to the right, forward and upward); 12 – connecting trunk to middle cervical ganglion; 13 – cardiac branch of SCSG; 14 – superior pharyngeal constrictor; 15 – pharyngo-basilar fascia; 16 – basilar part of occipital bone; CCA – common carotid artery; CS – carotid sinus; D – posterior belly of digastric; IJV – internal jugular vein; S – stylopharyngeus; SM – sternocleidomastoid; Black Arrowheads – hypoglossal nerve (elevated); White Arrowheads – glossopharyngeal nerve (elevated)