Stages in the growth of uroradiology.

For much of its history, uroradiology was dominated by the urologists. At the birth of the Radiological Society of North America, retrograde pyelography was well established. The major actors in the discovery of intravenous urography were urologists. Despite the availability of urography, the preeminence of retrograde pyelography was initially maintained because of its superior demonstration of the pelvicalyceal system. Selective renal angiography, high-dose intravenous urography, and nephrotomography provided excellent radiologic means for study of the renal parenchyma and put radiologists firmly in charge of uroradiology, a position further strengthened by the advent of ultrasonography and computed tomography.