Neonatal renal venous thrombosis: sequential ultrasonic appearances.

The ultrasonic appearances of three cases of renal venous thrombosis are shown. Initially the kidney is enlarged, echogenic and shows echogenic streaking that has a vascular or perivascular distribution. Subsequently thrombosis of renal veins or the inferior vena cava may be demonstrated and ultimately the kidney may recover or atrophy. The ultrasonic appearances will depend on the severity of the thrombosis and the stage at which the examination is performed.