A direct comparison of 50 normal supine and 50 normal upright phlebograms revealed a superiority of the supine technique in the opacification of the soleal and gastrocnemius sinusoids (90% vs. 72% and 74% vs. 26%, respectively). Of greater importance in relation to life-threatening thromboemboli, the supine method provided diagnostic studies of the pelvic veins more frequently than the upright technique (96% vs. 76%).