A primitive form of intravenous/excretory urography, a procedure used to visualize the upper urinary tract (by injection of contrast material) and diagnose cancer of the bladder, was developed by Fritz Voelcker and Alexander von Lichtenberg.1
- 1. Skrepetis, K., et al. "Controversies About Discovery and Development of Excretory Urography." Journal of Pelvic Medicine & Surgery. 10 (2004): 71-80.