Clinical correlations of postraumatic proton magnetic resonance changes in patients after mild traumatic brain injury
Dr. Stefan Sivak
Disclosure : This poster was supported by grant MZ SR č. 2007/57-UK-17
6 slide(s) – English – 2011-09-10
Structural brain magnetic resonance imaging (MRI) is typically normal in most patients after mild traumatic brain injury (MTBI). Protom magnetic resonance spectroscopy (1H-MRS) appears to be more sensitive and is able to detect subtle posttraumatic changes. The aim of our study was to evaluate the clinical significance of these changes.
This study investigated 8 MTBI patients and 8 sex, age and education-matched healthy controls. Both groups underwent neuropsychological testing, structural brain MRI (T1,T2*,FLAIR, DWI/ADC) and single-voxel 1H-MRS examination of both frontal lobes and upper brainstem (the patient group within 96 h after injury). Spectra were evaluated with standardized LCModel software. In order to avoid partial volume effects of CSF, only ratios of total N-acetylaspartate (NAA) to total creatine (Cre) and choline (Cho) were used for calculations.
Significant deficits of attention and working memory were found in MTBI patients during testing with Stroop Test (p=0,02) and Letter - Number Sequencing Test (p=0,05). Significant decrease of NAA/Cre (p=0,01) and (NAA+Cho)/Cr ratios (p=0,01) was found in right frontal lobe. These two 1H-MRS metabolite ratios in frontal lobe significantly correlated with Letter-Number Sequencing score (p=0,03; p=0,04) which represents working memory functioning. . In our group, only one patient lost consciousness directly after brain trauma.
No significant metabolite changes were present in upper brainstem voxel.
In this preliminary results, 1H-MRS appears to be sensitive to detect subtle traumatic changes in brain tissue after MTBI. These 1H-MRS changes seem to correlate with corresponding cognitive functions. These results warrant further study.