PREDICTORS OF ABNORMAL FINDINGS OF COMPUTED-TOMOGRAPHY OF THE HEAD INPEDIATRIC-PATIENTS PRESENTING WITH SEIZURES

Study objective: To develop a preliminary clinical decision guideline, using characteristics of ED pediatric patients presenting with seizur es, that successfully predicts all abnormal results of computed tomogr aphy (CT) of the head. Methods: We assembled a retrospective case seri es in the ED of a tertiary care children's hospital without trauma des ignation. The series comprised all patients who presented between Janu ary 1, 1992, and December 31, 1994, with seizures (febrile and afebril e) who underwent head CT as part of ED evaluation Results: Our inclusi on criteria were met by 203 patients. Of these patients, who had a med ian age of 3.1 years, 53% were boys; 18% had been transferred from ano ther facility; 25% had received anticonvulsant medication in the field , at the referring facility, or both; 32% had a history of seizures be fore the presenting episode; 6% had sustained a closed-head injury (CH I); 15% had a cerebrospinal fluid (CSF) shunt; 4% had an underlying ma lignancy or neurocutaneous disorder (NCT); and 30% had a documented fe ver. CT findings were abnormal in 25 patients (12%). CT showed evidenc e of hemorrhage in eight patients (32%), small focal abnormalities in four (16%), cerebral edema in three (12%), and shunt obstruction in tw o (8%). chi(2) Recursive-partitioning analysis revealed that CT scan r esults 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 minu tes or less, and did not have a history of a new-onset focal neurologi c deficit. Retrospective application of these criteria revealed that 4 1% of the CT scans could have been deferred. Conclusion: 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 b e considered.