Best Evidence Topic report: Is a CT head required for patients who present to the emergency department with a first seizure?

A short systematic review was undertaken to assess whether adult patients presenting to the ED with a first seizure require a CT head scan to rule out emergent intracranial pathology. MEDLINE, EMBASE, Cochrane and Google Scholar databases were searched. Seven relevant papers were identified. Study information, patient characteristics, key results and methodological weaknesses were tabulated. Our results indicate that adults presenting with a first seizure are a high-yield group for CT with a number needed to scan (NNS) between 10 and 19 for findings that would change management in ED, such as haemorrhage, infarction and tumours. We believe that this NNS is sufficiently low to justify the routine use of neuroimaging for these patients in emergency care.