Early detection of microstructural white matter changes associated with arterial pulsatility

Area of Science:

• Neuroimaging
• Cerebrovascular Health
• White Matter Integrity

Background:

• Increased cerebral blood flow pulsatility is common in vascular dementia and linked to white matter damage (leukoaraiosis, LA).
• Understanding pulsatility's role in early white matter changes is crucial for dementia prevention.

Purpose of the Study:

• To investigate the association between cerebral blood flow pulsatility and macro/microstructural white matter changes in older adults without dementia.
• To identify pulsatility as a potential early indicator of white matter damage.

Main Methods:

• Diffusion Tensor Imaging (DTI) was used to assess white matter microstructure.
• Measures included fractional anisotropy (FA) for microstructural integrity and radial diffusivity (RaD) for myelin integrity.
• Analysis controlled for age and leukoaraiosis (LA) severity.

Main Results:

• Increased arterial pulsatility was significantly associated with reduced white matter microstructural integrity (lower FA, higher RaD).
• Arterial pulsatility index was the strongest predictor of FA, followed by LA severity.
• Age was not a significant predictor of FA in this model.

Conclusions:

• Cerebral blood flow pulsatility is a sensitive index of white matter microstructural health in older adults.
• Elevated pulsatility may contribute to perivascular white matter damage and leukoaraiosis progression.
• Pulsatility monitoring could aid early detection of dementia risk and treatment assessment.