title: Antenatal diagnosis of agenesis of the corpus callosum.
abstract: OBJECTIVE
  To estimate the diagnostic performance of ultrasound in detecting agenesis of the corpus callosum (ACC).
  
  
  METHODS
  A retrospective review was performed of 1722 in utero MRI examinations. All cases were identified in which the fetus had been referred from ultrasonography with a diagnosis of ACC and those in which ACC was given as a diagnosis on the in utero MRI study. The MRI was assumed to provide the correct diagnosis of ACC and descriptive statistics of diagnostic accuracy for ultrasound were calculated.
  
  
  RESULTS
  Of the 1722 ultrasound examinations performed, 121 had a diagnosis of ACC and approximately 50% were confirmed at MRI. Forty-two fetuses with ACC not suspected at ultrasonography were also identified at MRI. Ultrasonography had a positive predictive value of 47% (95% CI: 38-56%) and a negative predictive value of 97% (95% CI: 96-98%) for detecting ACC.
  
  
  CONCLUSIONS
  Ultrasound is poor in diagnosing ACC and in utero MRI should be performed if there is any suspicion on antenatal ultrasonography.
authors.affiliation: Department of Neuroradiology, Leeds General Infirmary, Leeds, UK.
authors.forename: I
authors.initials: I
authors.lastname: Craven
authors.affiliation: Clinical Trials Research Unit, ScHARR, Sheffield, UK.
authors.forename: M J
authors.initials: MJ
authors.lastname: Bradburn
authors.affiliation: Academic Unit of Radiology, University of Sheffield, Sheffield, UK. Electronic address: p.griffiths@sheffield.ac.uk.
authors.forename: P D
authors.initials: PD
authors.lastname: Griffiths
mesh_terms: D061085:Agenesis of Corpus Callosum / Q000000981:diagnostic imaging*; D003337:Corpus Callosum / Q000000981:diagnostic imaging / Q000196:embryology / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods / Q000592:standards / Q000706:statistics & numerical data; D011237:Predictive Value of Tests; D011247:Pregnancy; D015203:Reproducibility of Results; D012189:Retrospective Studies; D016216:Ultrasonography, Prenatal / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data