Temporal lobe epilepsy in childhood: Clinical, EEG, and neuroimaging findings and syndrome classification in a cohort with new-onset seizures

Abstract

Sixty-three children with new-onset temporal lobe epilepsy (TLE) underwent extensive clinical, EEG, and neuroimaging investigation as part of a prospective, community-based cohort study of the natural history of TLE in childhood. Complex partial seizures occurred in 94% of the children, and tonic-clonic seizures occurred in 14%. Developmental, behavioral, or learning problems were present in 38%. Eighteen children (29%) had a significant illness/event prior to the onset of TLE, including febrile status epilepticus in seven, meningitis in four, respiratory arrest in two, and head injury in one. Magnetic resonance imaging or computed tomography revealed structural abnormalities of the temporal lobe in 24 children (38%), including hippocampal sclerosis (HS) in 13 and tumor in eight. There was a strong association between HS and a history of significant illness/event prior to the onset of TLE (p < 0.001). Analysis of past history and neuroimaging findings led us to propose three etiologically defined subgroups of TLE; developmental TLE (10 children with long-standing, nonprogressive temporal lobe tumors and malformations), TLE with HS/significant antecedents (18 children with HS or a history of a significant illness/event), and cryptogenic TLE (34 children with normal neuroimaging findings and no significant past history). Etiologic differences between children with new-onset TLE may confer prognostic information that will be useful for counselling families and planning treatment.

Mesial temporal sclerosis in children

“…No association was obtained between MTS side and cognitive defi ciency, delay in speaking or age focal seizure onset. The results in children submitted to surgery are equal to those found in adults 4 . Comparing the group of operated with that of non-operated patients of the present study, there was no statistically signifi cant difference regarding seizure control, but there was difference as concerns the used AED number, since the non-operated children used a higher number of AED, a fact directly related to control of seizures and consequently to the patients' quality of life.…”

“…In children with temporal lobe epilepsy, MTS is considered an infrequent etiology 4,5 , but with the advances in neuroimaging, MTS which was thought to be a disease of adults, started to be diagnosed at an increasingly younger age [6][7][8][9] .…”

A case of hippocampal sclerosis diagnosed as cortical dysplasia due to preoperative brain MRI finding

“…In both children and adults, hippocampal sclerosis is less frequently detected by MRI at the onset of temporal lobe epilepsy as compared to chronic refractory temporal lobe epilepsy [3][4][5] . The low prevalence of hippocampal sclerosis in early childhood suggests that MRI-detectable hippocampal sclerosis might be part of a multistage or progressive changes 6) .…”

Temporal lobe epilepsy in childhood: review article

“…The authors have concluded recently that this syndrome was an atypical presentation of benign epilepsy with centro-temporal paroxysms (5) . Harvey et al (6) studying clinical, electroencephalographic (EEG) and neuroimaging features of 63 children with recently diagnosed TLE, classified it in three subgroups, according to the etiology: TLE with developmental malformations (cortical dysgenesis, arachnoid cyst or low grade tumor), TLE with mesial temporal sclerosis (MTS) and significant antecedents (complex febrile seizure, traumatic brain injury or meningoencephalitis), and cryptogenic TLE. This latter group had a better seizure and psychological prognosis and may represent a benign syndrome of TLE.…”

“…They are characterized clinically by refractory complex partial seizures (CPS) with onset in childhood (16) . Pleomorphic xanthoastrocytoma is rare and affects adolescents and young adults (6) . Oligodendrogliomas are infiltrative tumors, which affect children with an incidence of 7-14% (8,9) .…”