ABSTRACT
AP (Fig. 2-1, A) and lateral (B) radiographs ofcommon carotid injection are shown. In this case the carotid bifurcation is just in front of the body of the C5 vertebra and the plaque does not ascend higher than the C4-5disc space. Difficulties can arise with an exposure at this low level, where the carotid artery dives deep to the sternocleidomastoid and omohyoid muscles. Anatomic structures that will be encountered and probably divided include the omohyoid muscle and some accessory branches from the jugular vein that are similar to the common facial vein but about three inches lower in anatomic location (see Fig. 3-9). The difficulties with a low bifurcation of this type are (1) securing enough exposure of the common carotid artery (CCA) to .ensure adequate placement of the Rummel tourniquet and (2) cross-clamping below that site in case placement of an indwelling shunt is needed. In the AP view (A) the internal carotid artery (ICA) swings laterally and thus a standard operating position will suffice. No unusual degree of head turning is required to adequately expose the ICA in this case.
