title: Prenatal diagnosis in pregnancies at risk for Joubert syndrome by ultrasound and MRI.
abstract: OBJECTIVE
  To describe the prenatal imaging findings in fetuses at risk for Joubert syndrome (JS), review the literature and propose a protocol for prenatal diagnosis of JS using ultrasound and MRI.
  
  
  METHODS
  We reviewed prenatal ultrasound and fetal MRI studies in two pregnancies at 25% recurrence risk for JS and correlated these findings with gross neuropathology in one affected fetus.
  
  
  RESULTS
  While abnormalities such as occipital encephalocele or enlarged cisterna magna have been identified before mid-trimester, the definitive diagnosis of JS, based on core cerebellar findings, has only been possible after 17 weeks' gestation.
  
  
  CONCLUSIONS
  With longitudinal monitoring, it is possible to diagnose JS in at-risk pregnancies before 24 weeks' gestation. On the basis of our data and review of the literature, we propose a protocol for monitoring pregnancies at risk for JS, utilizing serial ultrasounds combined with fetal MRI at 20-22 weeks' gestation to maximize the accuracy of prenatal diagnosis.
authors.affiliation: University of Washington/Children's Hospital and Regional Medical Center, Department of Pediatrics, Seattle, WA, USA. ddoher@u.washington.edu
authors.forename: Dan
authors.initials: D
authors.lastname: Doherty
authors.forename: Ian A
authors.initials: IA
authors.lastname: Glass
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Siebert
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Strouse
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Parisi
authors.forename: Dennis W W
authors.initials: DW
authors.lastname: Shaw
authors.forename: Phillip F
authors.initials: PF
authors.lastname: Chance
authors.forename: Mason
authors.initials: M
authors.lastname: Barr
authors.forename: David
authors.initials: D
authors.lastname: Nyberg
mesh_terms: D001259:Ataxia; D002531:Cerebellum / Q000002:abnormalities*; D005133:Eye Movements; D005260:Female; D005865:Gestational Age; D006801:Humans; D008607:Intellectual Disability; D008279:Magnetic Resonance Imaging; D008297:Male; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012307:Risk Factors; D013577:Syndrome; D016216:Ultrasonography, Prenatal