Thalamic microstructural alterations in cerebral small vessel disease with mild cognitive impairment: insights from diffusion kurtosis imaging.

Abstract

Purpose: This study aimed to investigate thalamic microstructural alterations in cerebral small vessel disease (CSVD) patients with mild cognitive impairment (MCI) using diffusion kurtosis imaging (DKI), and to examine the associations between DKI parameters and cognitive performance.

Methods: The study included 80 CSVD patients and 40 healthy controls (HC). Based on Montreal Cognitive Assessment (MoCA) scores, CSVD patients were divided into MCI (n = 40) and non-MCI (n = 40) groups. DKI parameters of the thalamus and its subregions were compared among the three groups and correlated with cognitive performance.

Results: CSVD-MCI patients exhibited significant alterations in DKI parameters, predominantly in the left thalamus. Compared to HC, CSVD-MCI patients showed reduced FA and decreased kurtosis parameters (KFA, MK, AK), along with increased diffusivity metrics (MD, AD, RD). Subregional analysis revealed the most pronounced changes in the left posterior, medial, and ventral groups. The lateral geniculate nucleus showed particularly significant reductions in FA and KFA. Cognitive assessments revealed significant correlations between DKI parameters and cognitive performance, with BNT and VFT scores showing strong correlations with DKI parameters in the left thalamus, particularly in the posterior nucleus and pulvinar.

Conclusion: Thalamic microstructural alterations may play a crucial role in cognitive decline among CSVD patients. Diffusion kurtosis imaging parameters may provide novel perspectives for investigating the mechanisms of cognitive deterioration in CSVD patients.