CT scan is not a good predictor of outcome in mild traumatic brain injury.
Traumatic Axonal injury associated with mild traumatic brain injury can be either hemorrhagic or non-hemorrhagic. While the axons themselves do not necessarily bleed when torn, small vessels in the vicinity may. The below article discusses the utility of CT scan as it applies to outcome and predictive outcome in mTBI. The authors confirm that other factors lead to a more accurate prognosis than CT scan. In fact, though not discussed, T-3 MRI will, in virtually all cases, demonstrate structural abnormality more accurately than CT scan in the mTBI case.
The CT scan has long been considered the "golden standard" for detecting abnormalities related to brain injury. However, clinicians and researchers have struggled to establish a good relationship between the results of a CT scan and the long-term prognosis of mild traumatic brain injury (mTBI).
A team of researchers from a leading medical center in the Netherlands recently studied the medical records of nearly 3,000 individuals with mTBI (those with a Glasgow Coma Scale score of 13-15). Their goal was to determine if the CT scan was a strong predictor of outcome six months after mTBI, and, if not-were there better predictors?
They found that the number of hemorrhagic contusions (fractures that cause bleeding in the skull) found using the CT scan was helpful in determining how well the mTBI patient recovered (the smaller the number, the better the recovery). However, age, extracranial injuries (injuries to the body), and day-of-injury alcohol intoxication were better predictors of recovery than CT scan results.
It is no surprise that older mTBI patients are less likely to have a good recovery than younger mTBI patients. It is also no surprise that mTBI patients with additional bodily injuries are less likely to have a good recovery. But that the presence of alcohol intoxication often predicts a good recovery was unexpected. The researchers suggest that alcohol intoxication in the patient could have lead to an underestimation of how severe the brain injury was at assessment.
In conclusion, their study outlined how factors other than CT scan results should be taken into consideration when determining how well a patient will recover.
Jacobs B, Beems T, Stulemeijer M, et al. Outcome prediction in mild traumatic brain injury: Age and clinical variables are stronger predictors than CT abnormalities. Journal of Neurotrauma. (December 2009).