title: MRI of acquired posterior urethral diverticulum following surgery for anorectal malformations.
abstract: BACKGROUND
  Posterior urethral diverticulum (PUD) is one of the most common postoperative complications associated with anorectal malformation (ARM) correction.
  
  
  OBJECTIVE
  To describe our MRI protocol for evaluating acquired PUD following ARM surgery, and associated imaging findings.
  
  
  METHODS
  Two radiologists retrospectively reviewed 61 pelvic MRI examinations performed for postoperative ARM for PUD identification and characteristics. Associated clinical, operative and cystoscopy reports were also reviewed and compared to MRI.
  
  
  RESULTS
  An abnormal retrourethral focus suspicious for PUD was identified at MRI in 13 patients. Ten of these patients underwent subsequent surgery or cystoscopy, and PUD was confirmed in five. All of the confirmed PUD cases appeared as cystic lesions that were at least 1 cm in diameter in two imaging planes. Four of the false-positive cases were punctate retrourethral foci that were visible only on a single MRI plane. One patient had a seminal vesical cyst mimicking a PUD.
  
  
  CONCLUSIONS
  Pelvic MRI can be a useful tool in the postoperative assessment of suspected PUD associated with ARM. Radiologists should have a high clinical suspicion for a postoperative PUD when a cystic lesion posterior to the bladder/posterior urethra is encountered on two imaging planes in these patients.
authors.affiliation: Department of Radiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave., Cincinnati, OH 45229, USA. Daniel.podberesky@cchmc.org
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Podberesky
authors.forename: Nicholas C
authors.initials: NC
authors.lastname: Weaver
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Anton
authors.forename: Taiwo
authors.initials: T
authors.lastname: Lawal
authors.forename: Miller C
authors.initials: MC
authors.lastname: Hamrick
authors.forename: Shumyle
authors.initials: S
authors.lastname: Alam
authors.forename: Alberto
authors.initials: A
authors.lastname: Peña
authors.forename: Marc A
authors.initials: MA
authors.lastname: Levitt
mesh_terms: D000293:Adolescent; D000071056:Anorectal Malformations; D001006:Anus, Imperforate / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D004240:Diverticulum / Q000209:etiology*; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D011183:Postoperative Complications; D012189:Retrospective Studies; D014522:Urethral Diseases / Q000175:diagnosis / Q000209:etiology*; D055815:Young Adult