Radionuclide venography in iliac and inferior vena caval obstruction.

Thirteen cases are presented to demonstrate normal and various abnormal radionuclide venographic patterns following obstruction of the inferior vena cava or common iliac veins. In these patients, obstruction was due to surgery, thrombosis, or neoplasm. Contrast venography was also performed in seven patients to confirm the radionuclide findings. Radionuclide venograms did not visualize the same collateral patterns that contrast venograms did. Most notably, the anterior parietal vessels were seen in many cases with radionuclide venography, and the paraspinal veins were seen more commonly with contrast venography.