title: Prenatal diagnosis of bladder exstrophy by fetal MRI.
abstract: OBJECTIVE
  To review our experience with prenatal diagnosis of bladder exstrophy by fetal magnetic resonance imaging (MRI). Bladder exstrophy can be diagnosed by ultrasonography (US) evaluation of the fetus based on absence of bladder filling, low-set umbilicus, small genitalia and lower abdominal mass, although in some instances more accurate anatomical information is desired.
  
  
  METHODS
  We studied three patients at mean gestational age of 27.3 weeks. The fetal MRI exam was performed on axial, sagittal, coronal planes and echo gradient in the best plan for acquisition of fetus. Images were analyzed by a group of three radiologists with experience in fetal MRI.
  
  
  RESULTS
  The MRI defined a lower abdominal mass prolapsing below the umbilical vessels, having the ureters ending on it in an anterior position. A cloacal malformation or a cloacal exstrophy could be excluded, as well as other accompanying spinal abnormalities. The renal system and oligohydramnios could be well documented.
  
  
  CONCLUSIONS
  The MRI showed a detailed scenario of the abnormality with advantages over the US evaluation in regard to excluding cloacal anomalies. MRI allowed accurate sexual differentiation and may be indicated after suspected bladder exstrophy on US evaluation.
authors: Department of Radiology, Federal University of São Paulo, São Paulo, Brazil.
authors: Susan
authors: S
authors: Goldman
authors: Patricia Oliveira
authors: PO
authors: Szejnfeld
authors: Atila
authors: A
authors: Rondon
authors: Viviane Vieira
authors: VV
authors: Francisco
authors: Herick
authors: H
authors: Bacelar
authors: Bruno
authors: B
authors: Leslie
authors: Ubirajara
authors: U
authors: Barroso
authors: Valdemar
authors: V
authors: Ortiz
authors: Antonio
authors: A
authors: Macedo
mesh_terms: D001746:Bladder Exstrophy / Q000473:pathology*; D005260:Female; D005315:Fetal Diseases / Q000473:pathology*; D005865:Gestational Age; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D016104:Oligohydramnios / Q000473:pathology*; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D014513:Ureter / Q000002:abnormalities*