title: Predictors of abnormal findings of computed tomography of the head in pediatric patients presenting with seizures.
abstract: OBJECTIVE
  To develop a preliminary clinical decision guideline, using characteristics of ED pediatric patients presenting with seizures, that successfully predicts all abnormal results of computed tomography (CT) of the head.
  
  
  METHODS
  We assembled a retrospective case series in the ED of a tertiary care children's hospital without trauma designation. The series comprised all patients who presented between January 1, 1992, and December 31, 1994, with seizures (febrile and afebrile) who underwent head CT as part of ED evaluation.
  
  
  RESULTS
  Our inclusion criteria were met by 203 patients. Of these patients, who had a median age of 3.1 years, 53% were boys; 18% had been transferred from another facility; 25% had received anti-convulsant medication in the field, at the referring facility, or both; 32% had a history of seizures before the presenting episode; 6% had sustained a closed-head injury (CHI); 15% had a cerebrospinal fluid (CSF) shunt; 4% had an underlying malignancy or neurocutaneous disorder (NCT); and 30% had a documented fever. CT findings were abnormal in 25 patients (12%). CT showed evidence of hemorrhage in eight patients (32%), small focal abnormalities in four (16%), cerebral edema in three (12%), and shunt obstruction in two (8%). chi 2 Recursive-partitioning analysis revealed that CT scan results were always normal when the patient did not have an underlying high-risk condition (malignancy, NCT, recent CHI, or recent CSF shunt revision), was older than 6 months, had sustained a seizure of 15 minutes or less, and did not have a history of a new-onset focal neurologic deficit. Retrospective application of these criteria revealed that 41% of the CT scans could have been deferred.
  
  
  CONCLUSIONS
  In this case series, the absence of defined high-risk factors predicted normal head CT findings. The deferral of emergency CT in this population should be considered.
authors.affiliation: Department of Pediatrics, University of Washington Emergency Services, Children's Hospital and Medical Center, Seattle, USA.
authors.forename: C R
authors.initials: CR
authors.lastname: Warden
authors.forename: D R
authors.initials: DR
authors.lastname: Brownstein
authors.forename: M A
authors.initials: MA
authors.lastname: Del Beccaro
mesh_terms: D001921:Brain / Q000000981:diagnostic imaging*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging; D002557:Cerebrospinal Fluid Shunts; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D006259:Craniocerebral Trauma / Q000000981:diagnostic imaging; D005260:Female; D006300:Health Services Misuse; D006801:Humans; D007223:Infant; D008297:Male; D016017:Odds Ratio; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012640:Seizures / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data