Ultrasound scanning for monitoring childhood hydronephrosis.

Ultrasound scanning of the kidneys in four children with radiologically proven hydronephrosis was undertaken with a new modification: scanning before and after copious intake of fluid. The anteroposterior diameter of the renal pelvis was used as an index of the hydronephrosis. Alterations in the dilatation were followed over a long period. Good agreement with simultaneous IVP was found. Improvement in the degree of hydronephrosis was apparent by reduction and disappearance of the dilatation of the pelvis during fasting as assessed by ultrasonic scanning, although pronounced dilatation was still observed after copious intake of fluid and at IVP. The results indicate that ultrasound scanning is a valuable supplement in the urological evaluation in children and that it can reduce significantly the number of radiological investigations required.