Electroencephalography in congenital malformations of the central nervous system

Abstract

SUMMARY -We studied clinical and EEG features of 36 cases with congenital malformations of the CNS. Patients were followed at the outpatient clinic of Hospital Cayetano Heredia and of Hogar Clinica San Juan de Dios in Lima-Peru, from January 1984 to June 1992. Eighty percent of the patients had convulsive syndromes and mental retardation. The most frequent malformation was agenesis of corpus callosum, and it was not possible to find a "typical" EEG pattern. The second were porencephalic cysts, with a good clinical-EEG correlation. There were two typical cases of schizencephaly, one of hemimegalencephaly with good prognosis, and one of holoprosencephaly. The results are compared to those obtained for a series we previously reported. Data discussed take into account reports on the subject registered in the literature. It is concluded that EEG is an useful method to evaluate possible CNS malformations in developing countries.KEY WORDS: central nervous system, congenital malformations, corpus callosum agnesis, porencephaly, hemimegalencephaly, hydrocephaly, EEG. Electroencefalografia e n las malformaciones congénitas del sistema nervioso centralRESUMEN -Estudiamos aspectos clínicos e del EEG de 36 casos de malformaciones congénitas del sistema nervioso central. Los pacientes fueron seguidos en los consultorios externos del Hospital Cayetano Heredia y del Hogar Clínica San Juan de Dios en Lima-Peru, desde enero 1984 hasta junio 1992. Ochenta por ciento de los pacientes presentaron sindrome convulsivo y retardo mental. La anormalidad mas frecuente correspondió a agenesia de cuerpo calloso y no fue posible identificar un patron EEG "típico". El segundo lugar correspondió a quistes porencefálicos, con buena correlación clínico-EEG. Ademas, hubieron dos casos clínicamente típicos de esquizencefalia, una hemimegalencefalia con buen prognóstico y un caso de holoprosencefalia. Se comparan los resultados con aquellos de casos previamente revisados. Se discuten los dados frente a la literatura acerca de los patrones EEG mas frecuentemente relatados. Se concluye en la utilidad del EEG en países en desarrollo para hacer posible un alto grado de sospecha de una malformación del SNC aun en ausencia de CAT-scan. PALABRAS-CLAVE: sistema nervioso central, malformaciones, agenesia de cuerpo calloso, porencefalia, hemimegalencefalia, holoprosencefalia, EEG.The congenital anormalies of the central nervous system (CNS) represent a frequent cause of fetal an d perinatal death . Together with congenital error s of th e metabolism, chromosomopathie s and vascular abnormalities, they play a major role in the pathology of the cerebral lesions responsible for mental retardatio n and/or cerebral paralysis, associate d o r not with convulsive syndromes 17 * 30 .

Clinical Pattern and Associated Comorbidities of Corpus Callosum Agenesis- A Tertiary Hospital Study

“…16 EEG findings of corpus callosum agenesis are nonspecific and interpretation of EEG is difficult since the frequent seizures caused by brain anomalies complicate the wave pattern of EEG. 5,[19][20][21] We found epileptic discharges in 65% cases and most commonly hypsarrhythmias, in 30% of cases. Marszal E et al 13 found hypsarrhythmia in majority of the cases in their study that was compatible with our study.…”

Agenesis of Corpus Callosum: Clinical Description and Etiology

“…Various neuropsychiatric disorders, including schizophrenia and attention-deficit hyperactivity disorder, have been described.2,4 Epilepsy has been reported as a frequent symptom in callosal agenesis. [1][2][3][4][5][12][13][14] Taylor and David observed it in 50% of cases.' Seizures are usually generalized or focal; however, epileptic syndromes, for example, infantile spasms in Aicardi's syndrome, are frequent in the youngest patients.1-4,12,14-17 Most authors report that EEG in agenesis of the corpus callosum shows nonspecific abnormalities, usually generalized slow waves.…”