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Dandy-Walker Malformation

Summary   Ultrasound Features   Differential Diagnoses   Syndromes   Images 2   Show All

Normal development of the rhombencephalon (hindbrain) is essential for the emergence of the pons, cerebellum (via the metencephalon) and medulla (via the myelencephalon) and their related cavity, the fourth ventricle. Arrest of this process has been proposed to result in a spectrum of abnormalities; consequences include persistence of the area membranacea superior, interruption of vermian development, and atresia of the foramina of Luschke and Magendie, which have all been implicated in the pathogenesis of the Dandy-Walker malformation. This malformation is characterised by: - hypoplasia or agenesis of the cerebellar vermis - dilatation and herniation of the fourth ventricle through this defect, seen as a large posterior fossa cyst, which displaces the adjoining falx, torcular and lateral sinuses. - hydrocephalus, which frequently accompanies the malformation. The Dandy-Walker variant has recently been defined; there are similar sonographic features, but there is both vermian and hemispheric hypoplasia in association with a less pronounced enlargement of the cisterna magna; in addition, hydrocephaly is not usually seen. Both conditions require differentiation from isolated enlargement of the cisterna magna (megacisterna magna) and from cerebellar dysgenesis.The Dandy-Walker malformation can be diagnosed accurately with prenatal sonography by demonstrating a prominent posterior fossa cyst communicating with the fourth ventricle through a defect in the cerebellar vermis. Splaying and separation of the cerebellar hemispheres is thus always seen. The transcerebellar view provides an optimal view of the posterior fossa, allowing for assessment of the cisterna magna; measurements exceeding 10 mm are abnormal, and require further evaluation. The classic Dandy-Walker malformation is commonly associated with varying degrees of hydrocephalus, which may be evident prenatally but will be apparent by three months of age in approximately 75% of patients. Approximately 70% of patients with Dandy-Walker malformation will have associated CNS anomalies, principally agenesis of the corpus callosum; other conditions include subependymal neuronal heterotopia, polymicrogyria, agyria, schizencephaly, lipoma of the corpus callosum, occipital encephalocele, lumbosacral meningocele, aqueductal stenosis, and holoprosencephaly. These have also been reported in association with the Dandy-Walker variant. Associated non-CNS anomalies are present in at least 25% of infants with classic Dandy-Walker malformation. These anomalies include congenital heart disease, renal malformations, low-set ears, polydactyly, syndactyly, Klippel-Feil syndrome, Cornelia de Lange syndrome, cleft palate, and facial angiomas. In Dandy-Walker variant the list may also include duodenal atresia, intrahepatic calcification, and two-vessel cord. The sonographic examination should thus be directed towards identifying additional supratentorial and extracranial anomalies, and should include fetal echocardiography, and follow-up sonograms are useful for monitoring cyst size and ventriculomegaly. Genetic syndromes associated with Dandy-Walker malformation include autosomal recessive disorders such as Meckel-Gruber, Walker-Warburg, and Joubert syndromes; the X-linked Aicardi syndrome; and other karyotypic anomalies such as duplications of 5p, 8p, and 8q, trisomies 9, 13, and 18, and triploidy. Trisomy 21 and partial trisomy 11q+ have also been noted with the Dandy-Walker variant. Fetal karyotyping is therefore recommended. Rubella, cytomegalovirus, toxoplasmosis, warfarin, isotretinoin and alcohol have all been associated with the Dandy-Walker malformation. In both the classic malformation and the variant, prognosis is usually dependent on the associated structural and chromosomal anomalies; in the absence of either, normal postnatal development is possible.The Dandy-Walker malformation can be diagnosed accurately with prenatal sonography by demonstrating a prominent posterior fossa cyst communicating with the fourth ventricle through a defect in the cerebellar vermis. Splaying and separation of the cerebellar hemispheres is thus always seen. The transcerebellar view provides an optimal view of the posterior fossa, allowing for assessment of the cisterna magna; measurements exceeding 10 mm are abnormal, and require further evaluation. The classic Dandy-Walker malformation is commonly associated with varying degrees of hydrocephalus, which may be evident prenatally but will be apparent by three months of age in approximately 75% of patients. Approximately 70% of patients with Dandy-Walker malformation will have associated CNS anomalies, principally agenesis of the corpus callosum; other conditions include subependymal neuronal heterotopia, polymicrogyria, agyria, schizencephaly, lipoma of the corpus callosum, occipital encephalocele, lumbosacral meningocele, aqueductal stenosis, and holoprosencephaly. These have also been reported in association with the Dandy-Walker variant. Associated non-CNS anomalies are present in at least 25% of infants with classic Dandy-Walker malformation. These anomalies include congenital heart disease, renal malformations, low-set ears, polydactyly, syndactyly, Klippel-Feil syndrome, Cornelia de Lange syndrome, cleft palate, and facial angiomas. In Dandy-Walker variant the list may also include duodenal atresia, intrahepatic calcification, and two-vessel cord. The sonographic examination should thus be directed towards identifying additional supratentorial and extracranial anomalies, and should include fetal echocardiography, and follow-up sonograms are useful for monitoring cyst size and ventriculomegaly. Genetic syndromes associated with Dandy-Walker malformation include autosomal recessive disorders such as Meckel-Gruber, Walker-Warburg, and Joubert syndromes; the X-linked Aicardi syndrome; and other karyotypic anomalies such as duplications of 5p, 8p, and 8q, trisomies 9, 13, and 18, and triploidy. Trisomy 21 and partial trisomy 11q+ have also been noted with the Dandy-Walker variant. Fetal karyotyping is therefore recommended. Rubella, cytomegalovirus, toxoplasmosis, warfarin, isotretinoin and alcohol have all been associated with the Dandy-Walker malformation. In both the classic malformation and the variant, prognosis is usually dependent on the associated structural and chromosomal anomalies; in the absence of either, normal postnatal development is possible.The Dandy-Walker malformation can be diagnosed accurately with prenatal sonography by demonstrating a prominent posterior fossa cyst communicating with the fourth ventricle through a defect in the cerebellar vermis. Splaying and separation of the cerebellar hemispheres is thus always seen. The transcerebellar view provides an optimal view of the posterior fossa, allowing for assessment of the cisterna magna; measurements exceeding 10 mm are abnormal, and require further evaluation. The classic Dandy-Walker malformation is commonly associated with varying degrees of hydrocephalus, which may be evident prenatally but will be apparent by three months of age in approximately 75% of patients. Approximately 70% of patients with Dandy-Walker malformation will have associated CNS anomalies, principally agenesis of the corpus callosum; other conditions include subependymal neuronal heterotopia, polymicrogyria, agyria, schizencephaly, lipoma of the corpus callosum, occipital encephalocele, lumbosacral meningocele, aqueductal stenosis, and holoprosencephaly. These have also been reported in association with the Dandy-Walker variant. Associated non-CNS anomalies are present in at least 25% of infants with classic Dandy-Walker malformation. These anomalies include congenital heart disease, renal malformations, low-set ears, polydactyly, syndactyly, Klippel-Feil syndrome, Cornelia de Lange syndrome, cleft palate, and facial angiomas. In Dandy-Walker variant the list may also include duodenal atresia, intrahepatic calcification, and two-vessel cord. The sonographic examination should thus be directed towards identifying additional supratentorial and extracranial anomalies, and should include fetal echocardiography, and follow-up sonograms are useful for monitoring cyst size and ventriculomegaly. Genetic syndromes associated with Dandy-Walker malformation include autosomal recessive disorders such as Meckel-Gruber, Walker-Warburg, and Joubert syndromes; the X-linked Aicardi syndrome; and other karyotypic anomalies such as duplications of 5p, 8p, and 8q, trisomies 9, 13, and 18, and triploidy. Trisomy 21 and partial trisomy 11q+ have also been noted with the Dandy-Walker variant. Fetal karyotyping is therefore recommended. Rubella, cytomegalovirus, toxoplasmosis, warfarin, isotretinoin and alcohol have all been associated with the Dandy-Walker malformation. In both the classic malformation and the variant, prognosis is usually dependent on the associated structural and chromosomal anomalies; in the absence of either, normal postnatal development is possible. Title: Disorders of the central nervous system Author: Paidas MJ, Cohen A Journal: Semin Perinatol 18: 266-282 Year: 1994 Title: Cerebellar vermian defects: antenatal sonographic appearance and clinical significance Author: Keogan MT, DeAtkine AB, Hertzberg BS Journal: J Ultrasound Med 13: 607-611 Year: 1994 Title: Sonographic detection of inferior vermian agenesis in Dandy-Walker malformations: prognostic implications microphthalamia, and cleft palate Author: Chang MC, Russell SA, Callen PW, Filly RA, Goldstein RB Journal: Radiology 193: 765-770 Year: 1994 Title: Closure of the cerebellar vermis: evaluation with second trimester US Author: Bromley B, Nadel AS, Pauker S, Estroff JA, Benacerraf BR Journal: Radiology 193: 761-763 Year: 1994 Title: Recurrent Dandy-Walker malformation Author: Obwegeser R, Deutinger J, Bernaschek G Journal: Arch Gynecol Obstet 255: 161-163 Year: 1994 Title: Complete trisomy 9: case report with ultrasound findings Author: McDuffie RS Journal: Am J Perinatol 11: 80-84 Year: 1994 Title: US case of the day Author: Wilson ME, Lindsay DJ, Levi CS, Ackerman TE, Gordon WL Journal: RadioGraphics 14: 678-681 Year: 1994 Title: First trimester transvaginal sonographic diagnosis of Dandy-Walker malformation Author: Achiron R, Achiron A, Yagel S Journal: J Clin Ultrasound 21: 62-64 Year: 1993 Title: Walker-Warburg syndrome: prenatal ultrasound findings Author: Vohra N, Ghidini A, Alvarez M, Lockwood C Journal: Prenat Diagn 13: 575-579 Year: 1993 Title: Goldston syndrome reconsidered Author: Moerman P, Pauwels P, Vandenberghe K, Lauweryns JM, Fryns JP Journal: Genet Couns 4: 97-102 Year: 1993 Title: Prenatal diagnosis of trisomy 9 mosaic presenting as a case of Dandy-Walker malformation Author: Bureau Y-A, Fraser W, Fouquet B Journal: Prenat Diagn 13: 79-85 Year: 1993 Title: Prenatal diagnosis of Dandy-Walker malformation in a family displaying X-linked inheritance Author: Cowles T, Furman P, Wilkins I Journal: Prenat Diagn 13: 87-91 Year: 1993 Title: Joubert syndrome associated with Leber amaurosis and multicystic kidneys Author: Ivarsson S-A, Bjerre I, Brun A, Ljungberg O, Maly E, Taylor I Journal: Am J Med Genet 45: 542-547 Year: 1993 Title: Axial sonographic features of Dandy-Walker variant with occipital cephalocele Author: Chiou Y-M, Tsai C-H Journal: J Clin Ultrasound 20: 139-141 Year: 1992 Title: Dandy-Walker variant: prenatal sonographic features and clinical outcome Author: Estroff JA, Scott MR, Benacerraf BR Journal: Radiology 185: 755-758 Year: 1992 Title: Antenatal sonographic features of Walker-Warburg syndrome: value of endovaginal sonography Author: Maynor CH, Hertzberg BS, Ellington KS Journal: J Ultrasound Med 11: 301-303 Year: 1992 Title: The Dandy-Walker syndrome: the value of antenatal diagnosis Author: Cornford E, Twining P Journal: Clin Radiol 45: 172-174 Year: 1992 Title: Enlarged cisterna magna and the Dandy-Walker malformation: factors associated with chromosome abnormalities Author: Nyberg DA, Mahony BS, Hegge FN, Hickok D, Luthy DA, Kapur R Journal: Obstet Gynecol 77: 436-442 Year: 1991 Title: Familial renal-hepatic-pancreatic dysplasia and Dandy-Walker cyst: a distinct syndrome? Author: Hunter AGW, Jimenez C, Tawagi FGR Journal: Am J Med Genet 41: 201-207 Year: 1991 Title: Dandy-Walker syndrome: a review of fifteen cases evaluated by prenatal sonography. Author: Russ PD, Pretorius DH, Johnson MJ Journal: Am J Obstet Gynecol 161: 401-406 Year: 1989 Title: Dandy-Walker cyst associated with occipital meningocele Author: Suzuki Y, Mimaki T, Tagawa T, Seino Y, Ohmichi M, Sugita N, Morimoto K, Yoshimine T Journal: Pediatr Neurol 5: 191-193 Year: 1989 Title: The Dandy-Walker malformation prenatal sonographic diagnosis and its clinical significance Author: Nyberg DA, Cyr DR, Mack LR, Fitzsimmons J, Hickok D, Mahony BS Journal: J Ultrasound Med 7: 65-71 Year: 1988 Title: Sonography of congenital midline brain malformations Author: Funk KC, Siegel MJ Journal: Radiographics 8: 11-25 Year: 1988 Title: Antenatal dignosis and obstetric mangement of Dandy Walker syndrome Author: Pilu G, Romero R, De Palma L, Rizzo N, Jeanty P, Copel JA, Bovicelli l, Hobbins JC Journal: J Reprod med 31: 1017-1022 Year: 1986 Title: Enlarged fetal cisterna magna: appearance and significance Author: Comstock CH, Boal DB Journal: Obstet Gynecol 66: 25S-28S Year: 1985 Title: The prenatal diagnosis of Joubert's syndrome of familial agenesis of the cerebellar vermis Author: Campbell S, Tsannatos C, Pearce JM Journal: Prenat Diagn 4: 391-395 Year: 1984 Title: Dandy-Walker syndrome: diagnosis in utero by means of ultrasound and CT correlations Author: Fileni A, Colosimo C, Mirk P, De Gaetano AM, Di Rocco C Journal: Neuroradiol 24: 233-235 Year: 1983 Title: Dandy-Walker syndrome: recognition by sonography Author: Taylor GA, Sanders RC Journal: AJNR 4: 1203-1206 Year: 1983 Title: Prenatal diagnosis of supernumerary der(22)t(11; 22) associated with the Dandy-Walker malformation in a fetus. Author: Chen CP; Liu FF; Jan SW; Yang YC; Lan CC Journal: Prenat Diagn Dec;16(12):1137-40 Year: 1996 Title: Dandy-Walker malformation diagnosed before 21 weeks of gestation: associated malformations and chromosomal abnormalities. Author: Ulm B; Ulm MR; Deutinger J; Bernaschek G Journal: Ultrasound Obstet Gynecol Sep;10(3):167-70 Year: 1997 Title: Meckel-Gruber syndrome concomitant with Dandy-Walker malformation: prenatal sonographic diagnosis in two cases. Author: Yapar EG; Ekici E; Dogan M; Gokmen O Journal: Clin Dysmorphol Oct;5(4):357-62 Year: 1996 Title: Antenatal diagnosis and management of Dandy-Walker syndrome. Author: Xiang Y; Chang X; Sun N; Xu Y; Ma S Journal: Chin Med Sci J Jun;11(2):103-5 Year: 1996 Title: Posterior fossa arachnoid cyst: an in utero mimicker of Dandy-Walker malformation. Author: Estroff JA; Parad RB; Barnes PD; Madsen JP; Benacerraf BR Journal: J Ultrasound Med Oct;14(10):787-90

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