Incidental diagnoses of Chiari I malformation are more and more frequent in pauci or asymptomatic children. The value of neurophysiological investigations for surgical indications is discussed.
Objective: To determine clinical presentations of Chiari I malformation and relative frequencies of severe and incidental forms, and to evaluate the usefulness of neurophysiological investigations for surgical indications.
Methods: This retrospective study included 34 patients admitted from 1984 to 2000, with Chiari I malformation diagnosis in different pediatric (intensive care, neurology and neurosurgery) units of a university hospital.
Results: The clinical presentation was severe (two children died) in four cases (12%). Signs of brain stem compression were found in 41% of cases, scoliosis in 21%, and incidental diagnosis in 26%. The polysomnography, performed in 12 cases, showed sleep-apneas in six cases. One child with an incidental diagnosis of Chiari I malformation had many sleep-apneas which required a surgical treatment. A surgical decompression was performed in 69% of cases, with clinical improvement in 77%.
Conclusion: The high incidence (12%) of severe forms revealing Chiari I malformations justifies systematic neurophysiological investigations for the initial evaluation and the follow-up of Chiari 1 malformations, including the less symptomatic forms.