Screening Ultrasound in Follow-up After Pediatric Pyeloplasty

Abstract

To investigate whether an initial ultrasound (US) adequately identifies those patients who need further investigation and possibly intervention while decreasing instrumentation and radiation exposure. The recommended imaging after pediatric pyeloplasty has included intravenous pyelography, radionucleotide renography, and ultrasound US. We retrospectively reviewed pediatric open pyeloplasty cases performed between 1999 and 2007. Of 116 patients reviewed, 49 met the inclusion criteria of unilateral pyeloplasty with pre- and postoperative US and mercaptoacetyltriglycine (MAG-3). Hydronephrosis was judged by anterior posterior pelvic diameter and caliectasis. Change in renal function on MAG-3 was defined as increase or decrease in function >5%. Of 49 patients, 42 (85.7%) showed improved or stable hydronephrosis postoperatively and 7 (14.3%) showed increased hydronephrosis. Forty-six (93.8%) patients had either improved or stable renal function. Of 42 patients with stable or improved hydronephrosis, 41 (97.6%) also had stable or improved function. Comparatively, of 7 patients with increasing hydronephrosis, 2 (28.6%) showed deteriorated renal function, P = .05. Postpediatric pyeloplasty imaging should aim to identify those who require further intervention. Our data demonstrate that at-risk patients can be identified with a sentinel US and selectively determine who needs further MAG-3 investigation. This should increase compliance while decreasing costs, instrumentation, and radiation exposure.