Predictive measures of cognitive outcome in adults sustaining brain injury.

摘要

To date, there is no consistent and accurate outcome prediction method for patients with traumatic brain injury (TBI). Commonly used clinical measures such as the Glasgow Coma Scale (GCS) and traditional radiological methods of x-rays and computed tomography (CT) scans do not always accurately predict patient functional outcome. These radiological methods are adequate in determining gross structural anatomical disturbances, however, they are unable to detect more diffuse cellular damage believed to be responsible for the functional impairments evidenced in patients sustaining TBI. Magnetic resonance imaging allows for various non-invasive sequencing techniques that have demonstrated to be a potentially valuable method of outcome prediction. Susceptibility weighted imaging (SWI) is superior at detecting microscopic vascular structure and abnormalities. Short and long echo MR spectroscopy (MRS) measures brain metabolites associated with various types of neuronal function. Abnormal metabolic levels associated with TBI are believed to represent and measure the more diffuse and microscopic damage associated with poor functional outcome. The purpose of this study was to determine whether the total hemorrhage volume and lesions number measured by SWI and metabolite ratios (Cho, Cre, NAA, mI, Glx, Cho/Cre, NAA/Cho, NAA/Cre, mI/Cre, & Glx/Cre) measured by single and regional multi-voxel MRS would predict long-term cognitive performance measured by the Neuropsychological Assessment Battery (NAB; Total memory, language, attention, spatial, and executive function) in adult patients sustaining traumatic brain injury. As hypothesized, SWI regional hemorrhage volume and number of lesion within the basal ganglia and thalamus, respectively, were predictive of long-term cognitive outcome measured by the NAB. Furthermore, the current study found that total and regional multi-voxel neurometabolites (NAA/Cre, NAA/Cho, and Cho/Cre) were predictive of long-term cognitive outcome as measured by the NAB. This study demonstrates that both, SWI and MRS, significantly contribute to the often elusive ability to predict long-term cognitive outcome for patients sustaining TBI which can potentially provide valuable information for post-trauma treatment and rehabilitation interventions.