Evidence for cervical cord tissue disorganisation with aging by diffusion tensor MRI

Area of Science:

• Neuroimaging
• Aging Research
• Spinal Cord Anatomy

Background:

• Normal aging impacts central nervous system structure and function.
• Cervical cord aging changes are not well understood.
• Association between brain and cervical cord aging is unclear.

Purpose of the Study:

• Investigate age-related changes in cervical cord volumetry and diffusivity.
• Assess MRI-detected abnormalities in the aging brain and cervical cord.
• Determine if brain and cervical cord aging abnormalities are associated.

Main Methods:

• Acquired conventional and diffusion tensor MRI of brain and cervical cord from 96 healthy subjects (13-70 years).
• Measured cervical cord cross-sectional area, mean diffusivity (MD), and fractional anisotropy (FA).
• Obtained brain white matter (WM) and grey matter (GM) volumetry and diffusivity metrics.

Main Results:

• Cervical cord FA significantly correlated with age (r=-0.70, p<0.001), unlike MD and cross-sectional area.
• Brain metrics including T2 lesion volume, normalized brain volume (NBV), GM volumes, and MD also correlated with age.
• Multivariate analysis identified cord FA, normalized cortical GM volume, and NBV as independent correlates of age (r2=0.76).

Conclusions:

• The aging cervical cord shows decreased FA without atrophy or MD changes, suggesting gliosis.
• Cervical cord is vulnerable to aging processes.
• Aging impacts both the brain and cervical cord, with distinct but partially correlated changes.