Anatomical study on valves of human facial veins.

The valves of the facial veins of 39 sides from 20 cadavers, aged 54-95 years, were investigated. Anatomical study of the valves is important, because the facial veins can be used for microvascular anastomosis in reconstruction in the head and neck. The present study confirmed that valves existed in the human facial veins, and were most frequently observed around the lower border of the mandible. When valves were classified into 5 types according to the morphology of the lobules, bicuspid valves were the most common (93.5%), followed by traced valves (4.1%), valve preparation (1.3%), and unicuspid valves (0.9%). However, no tricuspid valves were observed. Valves appeared most often (82.9%) at confluences with the facial veins. The length of valves in the trunk of the facial veins was twice the size of the inner diameter of the vessels in 78.4% of the cases. Therefore, when valves were observed at the anastomosis sites, the present results indicated that these valves could be avoided by resecting a length of about twice the inner diameter.