Magnetic resonance imaging of the dysplastic renal moiety and ectopic ureter

Purpose: We determined the role of magnetic resonance imaging (MRI) in symptomatic children with clinically suspected and radiologically occult dysplastic renal moieties and ectopic ureters. Materials and Methods: We reviewed clinical, imaging, cystoscopic, surgical and histological findings in 6 symptomatic children 1 to 15 years old with dysplastic renal moieties. Results: After multiple conventional imaging studies failed to delineate urinary tract anatomy MRI provided detailed multiplanar images of dysplastic renal moieties that; were diagnostic and predictive of subsequent intraoperative findings. Dysplastic upper pole moieties identified in 4 children were associated with ectopic ureters inserting into the vagina, prostatic urethra, bladder neck and bladder neck ureterocele in each. A solitary kidney with contralateral blind-ending ectopic ureters inserted into the bladder base in 2 cases. Pelvic cystic structures visualized by ultrasound in 3 patients were tortuous distal ureters on MRI. MRI specifically identified ureteral insertion sites that were not evident in 3 of the 5 patients who underwent cystoscopy. Conclusions: MRI may facilitate diagnosis, guide cystoscopy and aid in preoperative planning in children with poorly functioning renal moieties and ectopic ureters.