Electroencephalographic Abnormalities in Children with Single Calcified Neurocysticercosis Lesion: A Cross-Sectional Study

BACKGROUND: Neurocysticercosis (NCC) remains a major cause of seizures in low- and middle-income countries, often progressing to chronic epilepsy due to calcified granulomas. The role of electroencephalographic (EEG) in predicting prognosis and guiding treatment in calcified NCC remains uncertain. OBJECTIVE: The objective was to estimate the prevalence of surface EEG abnormalities in 5-18 years old seizure or epilepsy patients with single calcified neurocysticercosis lesion (CNL) and to understand the concordance of topographic anatomic localization to surface EEG abnormality localization, semiology localization. METHODS: This cross-sectional study was performed in a tertiary care center in northern India. Children with epilepsy aged 5-18 years with single CNL on computed tomography (CT) scan were screened and those with seizure onset at least a year prior to recruitment and receiving standard of care for epilepsy were enrolled. The demographic profile, clinical details including seizure semiology, localization and lateralization, treatment history, CNL topography on CT scan, EEG findings and other relevant investigations were obtained. RESULTS: Out of the 366 pediatric patients screened, 61 cases were enrolled. EEG was performed on 60 patients. Focal seizures were most noted (88%, n = 53/60). Clinical localization was to frontal lobe (73.5%), temporal lobe (22.6%), parietal and occipital lobe in one patient each. EEG showed interictal discharges and or background EEG abnormalities in 48% (n = 29/60, 95% CI: 35%-61%). Interictal EEG abnormalities predominantly localized to frontal (86%, n = 25/29), parietal (7%, n = 2/29), and occipital (7%, n = 2/29) region. EEG and clinical semiology-based localization showed 78% crude agreement (P value - 0.02). Concordance between seizure semiology localization and anatomic localization on CT was 80% (P value- 0.0009). CONCLUSIONS: There was significant concordance between clinical, electrical, and radiological localization of CNL. Frontal and temporal lobe were most common symptomatic zones for focal epilepsy in this cohort.