• Indications and timing of head CT scans in patients with a first-time seizure (FTS), who have returned to a normal baseline, are controversial.

• The range of such patients with abnormal head CT's is broad, at 3 to 41%.
   
• A retrospective study found that 22% of patients with a FTS and normal neurologic exams, had an abnormal head CT (Hennemen, et al).

• Another study found that in patients with suspected alcohol withdrawal seizures, 58% had an abnormal head CT, 16% of which were clinically significant findings (Earnest, et al).

• When feasible, neuroimaging of the brains of patients presenting with a FTS should be performed in the emergency department.  Deferred outpatient neuroimaging may be used when reliable follow-up is ensured. (Level B Recommendation).

References

• Earnest, et al. "Intracranial lesions shown by CT scans in 259 cases of  first alcohol related seizures." Neurology. 1988;38:1561-65.
• Henneman, et al. "Determining the need for admission in patients with new-onset seizures. Annal of Emerg Med. 1994;24:1108-14.
• Tardy, et al. "Adult first generalized seizure: etiology, biological tests, EEG, CT scan, in an ED.  Am Journal of Emerg Med. 1995;13:1-5.