title: Diagnostic imaging of posterior fossa anomalies in the fetus.
abstract: Ultrasound and magnetic resonance imaging are the two imaging modalities used in the assessment of the fetus. Ultrasound is the primary imaging modality, whereas magnetic resonance is used in cases of diagnostic uncertainty. Both techniques have advantages and disadvantages and therefore they are complementary. Standard axial ultrasound views of the posterior fossa are used for routine scanning for fetal anomalies, with additional orthogonal views directly and indirectly obtainable using three-dimensional ultrasound techniques. Magnetic resonance imaging allows not only direct orthogonal imaging planes, but also tissue characterization, for example to search for blood breakdown products. We review the nomenclature of several posterior fossa anomalies using standardized criteria, and we review cerebellar abnormalities based on an etiologic classification.
authors.affiliation: Department of Diagnostic Imaging, Sidra Medical and Research Center, Doha, Qatar. Electronic address: arobinson@sidra.org.
authors.forename: Ashley James
authors.initials: AJ
authors.lastname: Robinson
authors.affiliation: Department of Diagnostic Imaging, Sidra Medical and Research Center, Doha, Qatar.
authors.forename: M Ashraf
authors.initials: MA
authors.lastname: Ederies
mesh_terms: D002531:Cerebellum / Q000002:abnormalities* / Q000000981:diagnostic imaging; D003388:Cranial Fossa, Posterior / Q000000981:diagnostic imaging*; D003616:Dandy-Walker Syndrome / Q000000981:diagnostic imaging*; D002658:Developmental Disabilities / Q000000981:diagnostic imaging; D004453:Echoencephalography / Q000379:methods*; D006801:Humans; D008279:Magnetic Resonance Imaging; D009421:Nervous System Malformations / Q000000981:diagnostic imaging*; D011296:Prenatal Diagnosis / Q000379:methods*
keywords: Blake's pouch cyst; Cerebellar hypoplasia; Cerebellum; Dandy–Walker malformation; Persistent Blake's pouch; Posterior fossa