title: Higher-resolution MR elastography reveals early mechanical signatures of neuroinflammation in patients with clinically isolated syndrome.
abstract: To assess if higher-resolution magnetic resonance elastography (MRE) is a technique that can measure the in vivo mechanical properties of brain tissue and is sensitive to early signatures of brain tissue degradation in patients with clinically isolated syndrome (CIS).
  
  
  
  Seventeen patients with CIS and 33 controls were investigated by MRE with a 3T MRI scanner. Full-wave field data were acquired at seven drive frequencies from 30 to 60 Hz. The spatially resolved higher-resolution maps of magnitude |G*| and phase angle φ of the complex-valued shear modulus were obtained in addition to springpot model parameters. These parameters were spatially averaged in white matter (WM) and whole-brain regions and correlated with clinical and radiological parameters.
  
  
  
  Spatially resolved MRE revealed that CIS reduced WM viscoelasticity, independent of imaging markers of multiple sclerosis and clinical scores. |G*| was reduced by 14% in CIS (1.4 ± 0.2 kPa vs. 1.7 ± 0.2 kPa, P < 0.001, 95% confidence interval [CI] [-0.4, -0.1] kPa), while φ (0.66 ± 0.04 vs. 0.67 ± 0.04, P = 0.65, 95% CI [-0.04, 0.02]) remained unaltered. Springpot-based shear elasticity showed only a trend of CIS-related reduction (3.4 ± 0.5 kPa vs. 3.7 ± 0.5 kPa, P = 0.06, 95% CI [-0.6, 0.02] kPa) in the whole brain.
  
  
  
  We demonstrate that CIS leads to significantly reduced elasticity of brain parenchyma, raising the prospect of using MRE as an imaging marker for subtle and diffuse tissue damage in neuroinflammatory diseases. J. Magn. Reson. Imaging 2016;44:51-58.
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Fehlner
authors.affiliation: Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.|NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Janina Ruth
authors.initials: JR
authors.lastname: Behrens
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Kaspar-Josche
authors.initials: KJ
authors.lastname: Streitberger
authors.affiliation: NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Papazoglou
authors.affiliation: Institute of Medical Informatics, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Braun
authors.affiliation: NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Clinical and Experimental Multiple Sclerosis Research Center, Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
authors.forename: Judith
authors.initials: J
authors.lastname: Bellmann-Strobl
authors.affiliation: Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Clinical and Experimental Multiple Sclerosis Research Center, Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Klemens
authors.initials: K
authors.lastname: Ruprecht
authors.affiliation: NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Clinical and Experimental Multiple Sclerosis Research Center, Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin, Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.
authors.forename: Friedemann
authors.initials: F
authors.lastname: Paul
authors.affiliation: NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, Berlin, Germany.|Medical Image Analysis Center Basel, Switzerland.
authors.forename: Jens
authors.initials: J
authors.lastname: Würfel
authors.affiliation: Department of Radiology, Charité - Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Ingolf
authors.initials: I
authors.lastname: Sack
mesh_terms: D000328:Adult; D003711:Demyelinating Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D042241:Early Diagnosis; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques / Q000379:methods*; D004827:Epilepsy / Q000473:pathology* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D033081:Shear Strength; D013314:Stress, Mechanical
keywords: MR elastography; brain viscoelasticity; clinically isolated syndrome; in vivo multifrequency MRE; multiple sclerosis; white matter atrophy