Diffusion tensor imaging and gait in elderly persons with cerebral small vessel disease

Area of Science:

• Neurology
• Neuroimaging
• Geriatrics

Background:

• Cerebral small vessel disease (CSVD) is linked to gait issues.
• White matter lesions (WML) and lacunar infarcts are common CSVD markers.
• Conventional MRI may not fully capture microstructural integrity in WML or normal-appearing white matter (NAWM).

Purpose of the Study:

• To investigate the relationship between white matter integrity in WML and NAWM, and gait parameters.
• To assess if diffusion tensor imaging (DTI) can reveal associations not detectable by conventional MRI.
• To explore the role of microstructural integrity in gait disturbances in elderly individuals with CSVD.

Main Methods:

• 484 non-demented elderly individuals (50-85 years) with CSVD underwent MRI and DTI.
• Mean diffusivity and fractional anisotropy were measured in WML, NAWM, and regions of interest.
• DTI metrics were correlated with quantitative and semiquantitative gait parameters.

Main Results:

• Increased mean diffusivity in WML was inversely associated with gait velocity (β=-0.15; P=0.002).
• Similar inverse associations were observed in NAWM (velocity β=-0.21; P<0.001), even after adjusting for WML and lacunar infarcts.
• Fractional anisotropy showed a less consistent relationship with gait parameters.

Conclusions:

• White matter integrity, assessed by DTI in both WML and NAWM, is significantly associated with gait disturbances.
• These findings highlight the importance of microstructural integrity beyond conventional MRI detection.
• DTI provides valuable insights into the neural underpinnings of gait impairment in CSVD.