The relation between MRI measures of inflammation and neurodegeneration in multiple sclerosis

Area of Science:

• Neuroimaging
• Neurology
• Pathology

Background:

• Gadolinium-enhanced MRI and brain volume are used to assess multiple sclerosis (MS) disease activity and damage.
• Histopathology shows axonal damage correlates with inflammation in MS.
• In vivo MRI studies report a poor or absent correlation between brain tissue loss and gadolinium enhancement.

Purpose of the Study:

• To discuss the reasons behind the "inflammation/neurodegeneration mismatch" observed in multiple sclerosis (MS) using in vivo MRI.
• To propose strategies for improved in vivo characterization of MS pathology.

Main Methods:

• Review of existing literature on gadolinium-enhanced MRI and brain volume in MS.
• Analysis of histopathological findings in MS.
• Discussion of in vivo MRI study limitations.

Main Results:

• A significant disconnect exists between inflammatory changes (gadolinium enhancement) and neurodegeneration (brain tissue loss) in MS as seen by MRI.
• This "inflammation/neurodegeneration mismatch" complicates the assessment of disease progression.

Conclusions:

• Understanding the "inflammation/neurodegeneration mismatch" is crucial for accurate MS assessment.
• Developing advanced in vivo imaging techniques is necessary to better capture the complex pathology of MS.