“…Renal puncture is generally accepted as safe, whether for renal biopsy or for the diagnostic tapping of cysts. Percutaneous pyelography, an essential proliminary to this method, has been advocated in a number of papers over the past 15 years (Weens and Florence, 1954;Wickbom, 1954;Casey and Goodwin, 1955;Floyd and Guy, 1956;Lundin and Wadstrdm, 1965;Maldonado, 1956;Bosniak, Scheff, and Kaufman, 1968;Lalli, 1968). Yet one the renal pelvis has been located and visualized in this way the additional manoeuvre required for drainage is so simple that we can see little object in performing antegrade pyelography for obstruction without at the same time attempting percutaneous nephrostomy.…”