Predictive Factors for Abnormal Brain CT-Scan in Childhood Epilepsy at Yaoundé (Cameroon)

Purpose: Despite irradiation, CT-scan remains an important diagnostic tool in epilepsy in poor countries where MRI is neither available nor affordable. But many causes of epilepsy are not accessible to CT-scan and this technique remains expensive for many poor families in countries with limited resources. The aim of this study was to determine clinical or electroencephalogram variables which could predict brain CT-scan abnormalities in childhood epilepsy. Methods: It was a cross-sectional study including 151 epileptic children who underwent head CT-scan from October 2011 to march 2012, in one university-affiliated hospital in Cameroon (YGOPH). The data collected were clinical, type of seizure, Electroencephalogram and head CT-scans results. Independent predictive factors for CT abnormalities were sought by logistic regression. A p value < 0.05 was considered. Results: Of the 151 children, 54.3% (82/151) were boys (sex ratio: 1.18 M/1F). The median age was 54 months [2 - 190 months]; 74.8% of children were more than 2 years old but at the onset of epilepsy they were 2 years old or less. Birth asphyxia, mental retardation and neurologic deficit were respectively associated in 62.4%, 54.3% and 51.7% of cases. Eighty-five had focal epilepsy (56.3%), 61.6% had abnormal head CT-scan, 68.9% had abnormal EEG, with no significant gender difference. The factors most significantly associated with abnormal head CT-scan were: child age ≤ 2 years, maternal hypertension/eclampsy, cerebral palsy, and child microcephaly, with 89% to 92% abnormal CT. The two independent predictors of abnormal CT were patients’ age ≤ 2 years and microcephaly. The two main CT-scan lesions were cerebral atrophy (28.5%) and brain infarct (16.6%). None of these abnormalities was correlated to any type of epilepsy. Conclusion: Almost two-thirds of head CT-scan performed in epileptic children are abnormal in our setting. Patients of 2 years old or less and those with microcephaly are very likely to have brain anomalies on CT-scan. The most common brain lesions are atrophy, cerebral infarction and porencephalic cavities. Action to reduce birth asphyxia may lead to the reduction of the incidence of epilepsy in children.