Decrease of brain stiffness compared to loss of brain volume in Multiple Sclerosis patients

Background: Chronic inflammatory diseases of the CNS such as Multiple Sclerosis (MS) lead to demyelinization and to widespread degradation of neurons and axons. The loss of neurons and axons alters the mechanical structure and therefore the elasticity of the brain, a process which may be useable for early recognition of diffuse pathological degeneration [1]. Problem: Current knowledge of biomechanical properties of in vivo human brain is very limited. Nothing is known about the relationship between brain atrophy associated with MS and viscoelastic properties of the brain. To date magnetic resonance elastography (MRE) [2] is the only method capable to measure in vivo viscoelastic properties of the brain without intervention [3-6]. However, since MRE is sensitive to geometrical boundary conditions, it is important to systematically investigate volume effects in MRE of MS patients. Objective: Multifrequency magnetic resonance elastography (MRE) [4] and MRI volumetry [7] was applied to 17 MS patients and 42 ageand sex-matched healthy volunteers.