Diffusion tensor imaging (DTI) in the detection of white matter lesions in patients with mild cognitive impairment...

Area of Science:

• Neuroimaging
• Neurology
• Cognitive Science

Background:

• Mild cognitive impairment (MCI) is a known precursor to dementia, with amnestic MCI often progressing to Alzheimer's disease.
• Amnestic MCI with multiple domains (md-MCI) may progress faster than single-domain amnestic MCI (a-MCI).
• Identifying at-risk individuals is crucial for early intervention and management.

Purpose of the Study:

• To investigate white matter alterations in MCI subtypes using diffusion tensor imaging (DTI).
• To correlate DTI findings with neuropsychological test results in MCI patients.
• To differentiate between a-MCI and md-MCI using DTI metrics.

Main Methods:

• Diffusion tensor imaging (DTI) was used to measure fractional anisotropy (FA) and apparent diffusion coefficient (ADC).
• Forty-four a-MCI patients, 19 md-MCI patients, and 25 normal controls (NC) underwent DTI and cognitive testing.
• Specific white matter tracts analyzed included the corpus callosum, posterior cingulum (PC), anterior cingulum (AC), and superior longitudinal fasciculus (SLF).

Main Results:

• No significant differences in DTI measurements (ADC or FA) were found between the a-MCI and md-MCI subtypes.
• MCI patients showed increased ADC in the genu, PC, right SLF, and left AC compared to NC; FA remained largely unchanged.
• ADC and FA values correlated with verbal and visual memory test scores, with the strongest correlation between visual memory and right PC ADC.

Conclusions:

• DTI can detect white matter abnormalities in MCI patients, characterized by increased ADC in specific brain regions.
• Current DTI metrics do not distinguish between amnestic MCI subtypes (a-MCI vs. md-MCI).
• DTI indices show a significant correlation with cognitive performance, particularly in memory domains, highlighting DTI's potential as a biomarker for cognitive decline.