[Symptomatic Chiari type-II malformation in the neonatal period: a review of 4 cases].

Four newborn patients with symptomatic Chiari II malformations were studied retrospectively. Clinical manifestations and surgical results are presented. All of these patients had hydrocephalus, which was symptomatic in two patients from the first day of life. Three of them had bradycardia and apnea spells. Two patients had lower cranial nerve palsies. Cranial sonography was the first neuroimaging procedure used and it played an important role during the follow-up period, especially for the study of the hydrocephalus. Two newborns could be studied with Magnetic Resonance Imaging (MRI). It defined the level of the decent of the fossa posterior structures and the associated malformations. All of the patients were treated with surgical repair of the spinal dysraphism, ventricular shunt and decompressive surgery. Two patients died before the age of three months. Two other patients showed better evolution after their two year and four year check-ups, respectively. Bradycardia and apnea spells are features that worsen the prognosis as compared with other manifestations.