Lesion location in depression post traumatic brain injury using magnetic resonance spectroscopy: Preliminary results from a pilot study

Objective: To determine the metabolic status of the brain in post traumatic brain injury(TBI) depression using proton magnetic resonance spectroscopy (MRS). Design: Case-control study including 5 TBI depressed subjects and 5 age matched non-TBI non-depressed controls. Methods: Metabolic status was assessed using proton MRS. Ratios of N-acetylaspartate (NAA), choline (Cho) and total creatine (Cr) were calculated in frontal cortex, basal ganglia and thalamus. Results: NAA/Cho or NAA/Cr ratios were significantly reduced in the TBI depressed group compared to controls in frontal cortex, basal ganglia and thalamus. Conclusion: Reduced levels of NAA in frontal regions, basal ganglia and thalamus in TBI depression suggest neuronal damage or dysfunction which may be a associated with the primary brain injury or with depressed mood.