The lumens of the superior ophthalmic vein, the intraorbital communicating branch of the angular vein and the supraorbital vein of 19 adult male cadavers (38 orbits) were studied to find lunate venous valves in 79% of the cadavers, or 68% of the orbits. Of the 71 valves found, 39% were in the communicating branch of the angular vein, 58% in the supraorbital vein, and 2.8% in the superior ophthalmic vein. The mean distances from the valves in the communicating branch of the angular vein and those in the supraorbital vein to their junction to the superior ophthalmic vein were respectively 2.12 +/- 1.46 mm and 3.05 +/- 1.84 mm. It was important to note that the valvular sinuses opened toward the cavernous sinus.