Morphological study of the human maxillofacial venous vasculature: examination of venous valves using the corrosion resin cast technique

Abstract

Background: The venous drainage in the human head and neck, structures located superior to the heart, generally does not counter the force of gravity. Accordingly, venous valves in the human head have been reported to be few or nonexistent, and therefore the direction of venous drainage is variable and obscure.

Methods: We investigated whether venous valves were present in 13 heads of human adult cadavers using scanning electron microscopic observation of corrosive resin casts in the human maxillofacial region. This technique afforded the observation of the venous valves.

Results: Venous valves were found throughout the facial region. In particular, there were many valves distributed in the lingual, upper and lower labial, facial and pharyngeal veins. The venous valves were particularly well formed at motile parts of the maxillofacial region.

Conclusions: It is suggested that these valves may aid the venous blood return and permit the blood drainage in one direction.