Ultrasonographic evaluation of vertebral venous valves.

To date, vertebral venous valves have not been studied clinically or by sonography. This report reveals that these valves could be studied noninvasively by using sonographic techniques. Real-time sonography clearly showed the opening and closing of the two cusps of vertebral venous valves at the junction of the vertebral vein and the brachiocephalic vein, which move synchronously with the internal jugular venous valves. This is the first time the vertebral venous valves have been studied by using clinical sonography. This might provide a new point of view for evaluating the clinical significance of vertebral venous valves.