ABSTRACT
The external jugular (6) forms opposite the angle of the mandible (or ear lobe) from the posterior auricular vein (draining scalp behind ear) and the posterior branch of the retromandibular vein (formed by the maxillary and superficial temporal veins). It may be visible as it descends superficial to sternocleido - mastoid, toward the middle of the clavicle, to enter the subclavian (7) and it has a valve at its termination and one more proximally. It may be used for venous access, but care must be taken to avoid introducing air emboli. Structures in the posterior triangle, the neck, and the scapular muscles usually drain to the external jugular via the variable posterior jugular, supra - scapular and transverse cervical veins (11).
