The place of diagnostic ultrasound in the examination of kidneys not seen on excretory urography.

An examination was done on 28 patients with renal failure, 20 with unilateral hydronephrosis, 8 with multicystic kidneys, 3 with hypoplastic or chronically infected kidneys, and single examples of renal vein thrombosis, renal artery occlusion, xanthogranulomatous pyonephrosis with perinephric abscess, trauma and tumor invading the whole kidney. The distinct ultrasonic appearances of the various conditions causing radiographic non-visualization of the kidney are described.