title: Assessment of aged mdx mice by electrical impedance myography and magnetic resonance imaging.
abstract: BACKGROUND
  Similar to magnetic resonance imaging (MRI), electrical impedance myography (EIM) is dependent on the presence and location of water in muscle to assess neuromuscular diseases. We compared the 2 technologies in mdx mice to better understand their relationship.
  
  
  METHODS
  EIM and MRI, using T2 relaxation and diffusion-weighted imaging (DWI), were performed on the gastrocnemius of 10 mdx and 10 wild-type mice. Muscle function and tissue composition measurements were compared with the EIM and MRI data.
  
  
  RESULTS
  EIM reactance and T2 relaxation mapping can discriminate healthy from diseased mice (P <  .001 for both), but DWI could not. Both T2 relaxation and EIM reactance also correlated closely with muscle function/composition and with each other.
  
  
  CONCLUSIONS
  Given the low cost of EIM and the simplicity of application, it may be a valuable alternative to muscle MRI in Duchenne muscular dystrophy, where simple cumulative indices of muscle health are being sought.
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, Massachusetts, 02215, USA.
authors.forename: Jim S
authors.initials: JS
authors.lastname: Wu
authors.affiliation: Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Jia
authors.initials: J
authors.lastname: Li
authors.affiliation: Department of Radiology, Boston University Medical Center, Boston, Massachusetts, USA.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Greenman
authors.affiliation: Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, Massachusetts, 02215, USA.
authors.forename: David
authors.initials: D
authors.lastname: Bennett
authors.affiliation: Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Geisbush
authors.affiliation: Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Seward B
authors.initials: SB
authors.lastname: Rutkove
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D017097:Electric Impedance; D006909:Hydroxyproline; D008279:Magnetic Resonance Imaging; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018101:Mice, Inbred mdx; D018485:Muscle Fibers, Skeletal / Q000473:pathology; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology*; D009136:Muscular Dystrophies / Q000473:pathology* / Q000503:physiopathology*; D009213:Myography; D018709:Statistics, Nonparametric
chemical_list: D006909:Hydroxyproline
keywords: Duchenne muscular dystrophy; EIM; MRI; impedance; mdx mice; nerve conduction