Dandy-Walker syndrome: incidence in a defined population of Tabuk, Saudi Arabia

Dandy-Walker syndrome (DWS) is characterized by cystic dilatation of the 4t h ventricle and absence of the cerebellar vermis, There may also be posteri or fossa enlargement, hydrocephalus, hypoplastic cerebellar hemispheres and other malformations within and outside the central nervous system (CNS). T he condition is uncommon, and the incidence is unknown. We studied the inci dence of DWS in a defined Saudi Arabian population of military personnel an d their dependants. We identified all patients diagnosed with DWS during an 11-year period (1989-1999) from a cohort: of 45,274 live births. The incid ence of DWS was 1.0 per 100,000 live births per year. The incidence by sex per 100,000 live births per year was 1.24 for males and 0.78 for females. D WS formed 3.5% of our cases of infantile hydrocephalus. Copyright (C) 2001 S.Karger AG, Basel.