Research Reports - Role of the thalamus in natural recovery of cognitive impairment in patients with mild traumatic brain injury
Brain Inj. 2015 Nov 30:1-5. [Epub ahead of print]
Munivenkatappa A(1), Devi BI(2), Shukla DP(2), Rajeswaran J(3).
INTRODUCTION: Patients with mild traumatic brain injury (mTBI) may have normal
neuroimaging but manifest with a broad-spectrum of cognitive-deficits, which may
resolve eventually. The function of the thalamus in the process of
natural-recovery remains elusive. The current study investigates the role of the
thalamus in natural-recovery of cognitive-deficits in patients with mTBI.
METHODS: Twenty-one patients with mTBI were evaluated with an initial MRI scan,
within 36 hours of injury and assessed with neuropsychological tests(NPT) at 3-4
weeks after injury. First and second follow-up MRI and NPT were performed at 3-4
months and 6-7 months, respectively. The volume and tensor measures of the
thalamus and cognitive-scores were analysed at each assessment using
repeated-measures of variance. The association of cognitive-scores with
corresponding period imaging measures was analysed using bivariate-correlation.
RESULTS: Serial evaluation showed that all the cognitive-domains improved
significantly. During this period there was a significant increase in mean
thalamic volume (p = 0.049, effect-size = 0.18). After 3-4 months there was
emergence of anisotropic thalamo-cortical connections. At 2-3 weeks and 6-7
months after injury, the alterations in diffusivity values were positively
associated with improvement in memory-scores. Improvement in attention-scores
correlated significantly with changes in tensor values at the 6-7 months
CONCLUSION: The correlation between improvement in cognitive-scores and changes
in thalamic tensor and volume measures reflect the role of the thalamus in
natural-recovery after mTBI.