Nonlesional frontal lobe epilepsy (FLE) of childhood: clinical presentation, response to treatment and comorbidity.
BACKGROUND
Few studies have looked at long-term epileptic and cognitive outcome of frontal lobe epilepsy (FLE) in children. Most are limited by inclusion of lesional and nonlesional patients.


OBJECTIVE
To define the epileptic and functional outcome of children with nonlesional FLE.


METHODS
We reviewed medical records and neuropsychological evaluations of patients with nonlesional FLE diagnosed between 1994 and 2004. We included children with either focal or regional frontal EEG and/or functional imaging abnormalities. We reviewed their charts for seizure and neuropsychological outcome.


RESULTS
We included 21 children. Twelve (57.1%) presented with daily seizures. Seizures were nocturnal in 8 of 21, secondarily generalized in 6 of 21, adversive in 5 of 21, and focal motor in 6 of 21. Although, initial seizure control was poor in 14 of 21, long-term control was achieved in 10 of 21 after 14.6+/-22.3 months. Early development was normal in 12 of 21 but at later formal neuropsychological evaluation only 3 of 12 still had a normal profile. The majority of children had learning difficulties requiring special education prior to seizure onset (6 of 10). A clearly defined regression after seizure onset was observed in three children. The majority exhibited attention deficit and hyperactivity or impulsivity (14 of 21), behavioral problems (8 of 21), and cognitive impairments (10 of 21). Early seizure control was associated with a better cognitive outcome.


CONCLUSIONS
Nonlesional FLE is associated with poor seizure and behavioral outcomes. Whether this is secondary to MRI-silent developmental lesions or to the progressive repercussion of seizures on frontal lobe functions remains uncertain. A prospective study with early neuropsychological assessment could help confirm the latter.
Prévost
Julie
J
Department of Pediatrics, Division of Neurology, Sainte-Justine Hospital, University of Montreal, Montreal, Canada.
Lortie
Anne
A
Nguyen
Dang
D
Lassonde
Maryse
M
Carmant
Lionel
L
D000367:Age Factors; D000927:Anticonvulsants / Q000627:therapeutic use; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000453:epidemiology; D002648:Child; D002653:Child Behavior Disorders / Q000175:diagnosis / Q000453:epidemiology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000453:epidemiology; D015897:Comorbidity; D017034:Epilepsy, Frontal Lobe / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007859:Learning Disabilities / Q000175:diagnosis / Q000453:epidemiology; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D049268:Positron-Emission Tomography; D011379:Prognosis; D011792:Quebec / Q000453:epidemiology; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon; D016896:Treatment Outcome
D000927:Anticonvulsants