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

Kim, Gab Teug

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.