Development of Clinical Criteria for Indication of Computed Tomography (CT) Scans in Minor Head Injury Patients

ABSTRACT

PURPOSE: Most minor head injury (MHI) patients can be discharged without complication but a small percentage of these patients have intracranial lesions which can be observed by computed tomography (CT), and in these cases, neurosurgical intervention may be necessary. Selective use of the CT-scan in cases of MHI is important in reducing the risks associated with unnecessary radiation exposure. We conducted a retrospective study with the goal of creating a set of clinical criteria for deciding when to utilize the CT scan for MHI cases. METHODS: This retrospective study was conducted using 1,735 patients with MHI (GCS=15, > or =6 years old) from January 2009 to December 2010. Based on literature review results, we selected risk factors associated with the presence of intracranial lesions observable by cranial CT-scan, which may have resulted from MHI. The detection of intracranial lesions by CT scan was regarded as the primary clinical outcome. RESULTS: Of the total cases, 87(5.0%) had intracranial lesions as observed by CT scan. All patients with abnormal CT scans had at least one of the following risk factors headache, loss of consciousness (LOC)/posttraumatic amnesia (PTA), vomiting, focal neurological deficit, coagulopathy, alcohol intoxication, skull fracture, age greater than 65 years, dangerous mechanism of injury, or facial fracture. A decision model for application of CT scanning in MHI cases was derived which consisted of 5 risk factors headache, LOC/PTA, skull fracture, and age greater than 65 years. The decision model was 100% sensitive (95% CI, 95.8~100%) and 42.4% specific (95% CI, 40.0~44.8%) for predicting intracranial lesions, and would require only 59.8% of patients to undergo CT. CONCLUSION: The decision model developed for CT scanning in MHI cases was highly sensitive. Patients who meet the criteria of the model require evaluation by CT scan.