MORPHOLOGICAL-STUDY OF THE HUMAN MAXILLOFACIAL VENOUS VASCULATURE - EXAMINATION OF VENOUS VALVES USING THE CORROSION RESIN CAST TECHNIQUE

Background: The venous drainage in the human head and neck, structures located superior to the heart, generally does not counter the force o f gravity, Accordingly, venous valves in the human head have been repo rted to be few or nonexistent, and therefore the direction of venous d rainage is variable and obscure.Methods: We investigated whether venou s valves were present in 13 heads of human adult cadavers using scanni ng electron microscopic observation of corrosive resin casts in the hu man maxillofacial region. This technique afforded the observation of t he venous valves. Results: Venous valves were found throughout the fac ial region. In particular, there were many valves distributed in the l ingual, upper and lower labial, facial and pharyngeal veins. The venou s valves were particularly well formed at motile parts of the maxillof acial region. Conclusions: It is suggested that these valves may aid t he venous blood return and permit the blood drainage in one direction. (C) 1996 Wiley-Liss, Inc.