Importance of routine vascular nephrotomography in excretory urography.

The rapid intravenous injection of a large bolus of contrast medium produces a vascular as well as a tubular nephrogram. They are additive but the vascular phase is early, intense, and brief whereas the tubular phase is less intense but more prolonged. The addition of tomography during either phase improves visualization of the renal parenchyma and its outline. A comparison study of tomography during the vascular phase (vascular nephrotomography) with that at five minutes demonstrated the superiority of the former. Our technique, data, and illustrative case abstracts are presented.