White matter changes measured by multi-component MR Fingerprinting in multiple sclerosis.

Area of Science:

• Radiology and Imaging
• Neuroscience
• Medical Physics

Background:

• Multiple sclerosis (MS) is characterized by T2-hyperintense lesions, but surrounding white matter is also affected.
• Conventional MRI often underestimates the full extent of white matter damage in MS.

Purpose of the Study:

• To develop and validate a novel quantitative MRI method to visualize and measure white matter tissue changes in MS.
• To compare the extent of these changes with conventional FLAIR MRI findings.

Main Methods:

• Employed a fast, multi-parametric quantitative MRI approach using multi-component MR Fingerprinting (MC-MRF).
• Analyzed MRF scans using joint-sparsity multi-component analysis to obtain magnetization fraction maps.
• Assessed differences in a component with prolonged relaxation times between MS patients and controls.

Main Results:

• Identified an additional MRF component with increased transverse relaxation times in MS patients, likely representing altered free water content.
• MS patients showed a significantly higher volume of this prolonged relaxation time component in white matter compared to healthy controls.
• This MRF component moderately correlated with FLAIR-identified white matter damage and was more extensive in 73% of MS patients.

Conclusions:

• The developed MC-MRF method effectively captures white matter tissue changes in MS patients.
• This quantitative approach reveals more extensive white matter damage than visually detectable on conventional FLAIR MRI.
• MC-MRF offers a novel and more comprehensive way to quantify white matter pathology in MS.