High-yield criteria for urgent cranial computed tomography scans.

We conducted a study to establish high-yield criteria for urgent cranial computed tomography (CT) scanning in both medical and surgical conditions. Patients were scanned on an emergency basis and were entered in the study if they met preestablished criteria. The clinical findings of the 407 patients in this study were correlated with CT findings. The majority were scanned on an emergency basis for the following reasons: trauma, seizures, altered mental status, hemiparesis, headache, and coma. The yield for CT scans that altered patient management was moderate to high for each of the following categories: coma, 46%; trauma, 30%; seizures, 23%; hemiparesis, 22%; and headache, 21%. The yield for altered mental status and reasons outside the established criteria were fairly low, 8% and 7%, respectively. The specific clinical correlation with CT results in each category is discussed.