Prenatal diagnosis and perinatal management of frontoethmoidal meningoencephalocele.

Frontoethmoidal meningoencephaloceles (FEM) are exceedingly rare in the western hemisphere, Australia, and Europe with an estimated frequency of 1 in 40,000 live births. Among the inhabitants of Thailand, Burma, Malaysia, Indonesia, and parts of the Soviet Union, however, the frequency is as high as 1 in 5000, accounting for 15% of all neural tube defects (NTD). Normal maternal serum alpha-fetoprotein (MSAFP) values usually will be found in these cases since most encephaloceles are closed, skin covered defects. Correct interpretation of the sonographic findings is crucial in establishing a diagnosis as well as giving prognostic and recurrence risk information. To our knowledge, this is the first reported case of prenatally diagnosed FEM. Perinatal management, differential diagnosis for disorders associated with this malformation, and epidemiologic information regarding this rare condition are discussed. It is anticipated that the prenatal sonographic findings may be applied to establish this diagnosis in similarly affected fetuses.