Congenital hydrocephalus--analysis of 49 cases.

The causes of congenital hydrocephalus vary widely and have an important effect in determining the future counseling of affected cases. We analyzed the postmortem findings of 49 autopsies diagnosed as hydrocephalus to find the causes and related conditions. The cases were collected during the last 10 years (1981-1990). The cases consisted of 25 cases associated with various congenital malformations of the central nervous system (CNS), 14 cases of posthemorrhagic hydrocephalus, 4 cases of postinfection hydrocephalus, and 2 cases of hydranencephaly. Four cases were associated with supracerebellar arachnoid cyst (1) and unknown causes (3). Twenty-five cases associated with congenital malformation of the CNS consisted of 10 cases of holotelencephaly, 5 cases of stenosis of the Sylvian aqueduct, 4 cases of agenesis of the corpus callosum, and 3 cases each of Dandy-Walker malformation and Arnold-Chiari malformation. Various malformations of other organs were associated with these cases. Cardiovascular malformations were common, consisting of 11 cases of patent ductus arteriosus (PDA), 7 cases of atrial septal defect (ASD), and 6 cases of patent foramen ovale (PFO). Among the anomalies of the respiratory system, abnormal lobation was commonly associated, as well as hypoplasia of the lung. Gastrointestinal malformations included Meckel's diverticulum, diaphragmatic hernia, mobile intestine, and midline small liver. Cryptorchidism was the most common malformation in the genitourinary system. Holotelencephaly cases showed multiple craniofacial anomalies, as well as other malformations in the central nervous system. Skeletal malformations included polydactyly, simian crease, and flexion deformity. There were no specific constellations of malformations in these different groups of CNS malformations associated with hydrocephalus.