Venous valves of the head and neck: a narrative review

Classical anatomical teaching has long described head and neck veins as largely valveless, allowing free bidirectional flow. Modern cadaveric, imaging, and surgical studies challenge this oversimplification.

This narrative review synthesises current anatomical evidence regarding the presence, morphology, distribution, and functional significance of venous valves throughout the head and neck venous system.

A literature search was conducted across PubMed and Semantic Scholar. The review was structured following the Scale for the Assessment of Narrative Review Articles (SANRA) quality framework. All primary research references were verified against PubMed.

Valves have been documented in the facial, lingual, labial, pharyngeal, superior ophthalmic, superficial temporal, glabellar/forehead, external jugular, and internal jugular veins, as well as at the lymphovenous junction. These valves are predominantly bicuspid and cluster near venous junctions. The internal jugular vein has a valve near its termination in approximately 86-93% of specimens; functional competence is context-dependent, being present in patients with normal central venous pressure but frequently absent in those with chronically elevated pressure, and further compromised by cannulation trauma. Jugular venous reflux from valve insufficiency has been associated with several neurological conditions. The cerebral venous system, dural sinuses, emissary veins, and the internal vertebral venous plexus are consistently valveless.

Contemporary evidence demonstrates that head and neck veins are not uniformly valveless. Valve presence and competence carry implications for infection spread, microvascular surgery, central venous cannulation, and cerebral hemodynamics.