[Contrast extravasation from the pelvicalycine system during infusion pyelography (author's transl)].

Rupture of the pelvicalycine systems is occasionally observed during infusion pyelograms. Twenty such cases are reported. The usual cause was the presence of stones in the ureter leading to urinary tract obstruction and acute pressure rise in the pelvicalycine system. The anatomical and physiological basis for the rupture is outlined. Subsequently our own cases are described. In 13 patients rupture occurred without previous renal abnormality; in these there was always spontaneous healing once the obstruction had been removed. In five patients rupture occurred in a previously damaged kidney; the changes at the point of rupture and the subsequent possible complications are described. Two cases should be mentioned in detail; in these, rupture persisted and lead to the development of a retroperitoneal pseudocyst. Only one similar case is reported in the literature since 1966.