John Libbey Eurotext

Médecine de la Reproduction


Dandy-Walker malformations and other cystic malformations of the posterior fossa Volume 12, issue 2, avril-mai-juin 2010

Service de radiologie, hôpital d'enfants Armand-Trousseau, 26, avenue du Docteur-Arnold-Netter, 75012 AP-HP, Paris, France, Service d’imagerie pédiatrique et fœtale, hôpital Femme-Mère-Enfant, hospices civils de Lyon, 59, boulevard Pinel, 69500 Lyon, France

Knowledge of the main embryologic milestones leading to the development of the posterior fossa structures makes it possible to understand genesis of the posterior fossa cysts. The theory developed by Robinson is reminded. Detailed semiological analysis in US and/or MRI makes it possible to diagnose most cystic malformations of the posterior fossa: vermian axis, morphology, biometry, orientation and insertion of the tentorium cerebelli, visibility of the walls of the Blake's pouch in US, possible mass effect on the structures of the posterior fossa. The main semiological characteristics of the Blake's pouch cyst, the Dandy-Walker malformation and the arachnoid cysts are reminded.