Deans' stroke musings: Viscoelasticity of subcortical gray matter structures

Would this be useful to determine the damaged areas in stroke so we could map stroke protocols to them to recover? Has your doctor done any analysis to map damage to recovery protocols? Stupid question I know, your doctor has no protocols and doesn't know what damage there is in your brain. S/he is flying totally blind in any attempt to get you 100% recovered. Everything in stroke is a complete failure, what is your stroke hospital and doctor doing to fix that? ANYTHING AT ALL?
https://www.ncbi.nlm.nih.gov/pubmed/27401228

Johnson CL^1,², Schwarb H¹, D J McGarry M³, Anderson AT^1,⁴, Huesmann GR^1,^5,⁶, Sutton BP^1,⁷, Cohen NJ^1,⁸.

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Abstract

Viscoelastic mechanical properties of the brain assessed with magnetic resonance elastography (MRE) are sensitive measures of microstructural tissue health in neurodegenerative conditions. Recent efforts have targeted measurements localized to specific neuroanatomical regions differentially affected in disease. In this work, we present a method for measuring the viscoelasticity in subcortical gray matter (SGM) structures, including the amygdala, hippocampus, caudate, putamen, pallidum, and thalamus. The method is based on incorporating high spatial resolution MRE imaging (1.6 mm isotropic voxels) with a mechanical inversion scheme designed to improve local measures in pre-defined regions (soft prior regularization [SPR]). We find that in 21 healthy, young volunteers SGM structures differ from each other in viscoelasticity, quantified as the shear stiffness and damping ratio, but also differ from the global viscoelasticity of the cerebrum. Through repeated examinations on a single volunteer, we estimate the uncertainty to be between 3 and 7% for each SGM measure. Furthermore, we demonstrate that the use of specific methodological considerations-higher spatial resolution and SPR-both decrease uncertainty and increase sensitivity of the SGM measures. The proposed method allows for reliable MRE measures of SGM viscoelasticity for future studies of neurodegenerative conditions. Hum Brain Mapp 37:4221-4233, 2016.