Are MRI‐detected brain abnormalities associated with febrile seizure type?

Abstract

SUMMARY Objective: Whether magnetic resonance imaging (MRI) is informative in febrile seizures (FS) is unknown. We undertook a study to determine the frequency of MRI-detected brain abnormalities andFebrile seizures (FS) are common, affecting 2-5% of children by 6 years of age (van den Berg & Yerushalmy, 1969;Verity et al., 1985) and are associated with an increased risk of subsequent epilepsy. Epilepsy develops in 2-4% of children with a history of FS, four times more fre- (Nelson & Ellenberg, 1978;Annegers et al., 1979;Verity et al., 1985).Computed tomography (CT) scans are not recommended in FS (NIH, 1980;Al-Qudah, 1995), although preexisting brain abnormality has been proposed (Annegers et al., 1987) to explain the observation that complex, but not simple, FS are associated with increased risk for focal epilepsy. Several pathologies (Mathern et al., 1995;Lado et al., 2000), including mesial temporal sclerosis (MTS), may account for associations between prolonged FS and later epilepsy, but the scarcity of data limit conclusions. While there have been two studies of magnetic resonance imaging (MRI) in febrile status epilepticus (SE) 765 766 D. C. Hesdorffer et al. (VanLandingham et al., 1998;Scott et al., 2003), MRI studies are lacking in cohorts with simple and complex FS of shorter duration, where such studies could contribute to understanding why children experience FS.We undertook a prospective study of children with first FS (1) to determine the proportion with MRI-detected brain abnormalities, and (2) to evaluate whether these abnormalities were more common among children with complex FS than among those with simple FS or were associated with specific features of complex FS. METHODS Study subjectsIn this prospective cohort study, we identified children, aged 6 months to 5 years, with first FS by daily screening of The Morgan Stanley Children's Hospital of New YorkPresbyterian Pediatric Emergency Department log and by review of pediatric hospital discharges with an ICD-9 code of 780.3 between March 1999 and April 2004. We defined FS as seizures occurring among children with a rectal temperature of at least 101• Fahrenheit (38.3 o C), in the absence of a history of unprovoked seizures or concurrent central nervous system infection (NIH, 1980). Children with prior neonatal seizure were included.Upon identification, we contacted the child's primary care physician to request permission for the study team to contact the child's parents or guardians. After obtaining permission from the parent, the physician notified the study team and the family was contacted to explain the study and offer participation. Measures and proceduresIf initial screening confirmed the first FS, we obtained informed consent and the child received an MRI of the brain within 1 week of the FS. Within 1 month, parents were interviewed regarding the child's medical history, demographics, and family history of FS and epilepsy in firstdegree relatives. At the parent interview, children received a neurological examination, which was classifie...

Risk factors for subsequent febrile seizures in the FEBSTAT study

“…Consistent with the Columbia first febrile seizure study, MRI abnormalities were 4.3-fold more common in children with focal and prolonged FS 5 compared to children with SFS (95% CI: 12.–15.0) and with baseline data in the FEBSTAT study 12 in whichchildren with FSE were more likely to have any MRI abnormality versus those with SFS. Increased T2 signal accounted for an increased risk for subsequent FSE in those with a first FS that was FSE.…”

“…5–7 FSE was defined as a seizure lasting 30 minutes or more. Subjects with FSE were recruited from Emergency Departments of five sites for FEBSTAT.…”

Quantitative Evaluation of Medial Temporal Lobe Morphology in Children with Febrile Status Epilepticus: Results of the FEBSTAT Study

“…FSE was defined as a provoked seizure where the sole acute provocation was fever (temperature >38.4°C, 101.0°F) without prior history of afebrile seizures and without evidence of an acute CNS infection or insult 11 . The 226 FSE subjects in this study were enrolled from three prospective studies as described previously 12 : 191 from the FESBSTAT cohort 9 , 23 from the Duke FEBSTAT pilot study 13 , and 12 from the Columbia first FS study 14 . A control group consisting of 96 children who presented with a simple febrile seizure (SFS) and who underwent baseline MRI imaging similar to those with FSE were also obtained from the Columbia study 14 .…”

Fieberkrampf und Magnetresonanztomographie

“…B. Malformationen) als vorbestehend und als Prädisposition für eine erniedrigte Krampfschwelle angesehen wurden [10]. Es bleibt allerdings unklar, warum insbesondere die ödemver-dächtigen MRT-Auffälligkeiten im Marklager Ursache der Anfälle und nicht doch eher deren Folge sein sollen.…”