title: Electrical impedance myography in the evaluation of the tongue musculature in amyotrophic lateral sclerosis.
abstract: BACKGROUND
  Electrical impedance myography (EIM) quantifies muscle health and is used as a biomarker of muscle abnormalities in neurogenic and myopathic diseases. EIM has yet to be evaluated in the tongue musculature in patients with amyotrophic lateral sclerosis (ALS), who often show clinical bulbar signs.
  
  
  METHODS
  The lingual musculature of 19 subjects with motor neuron disease and 21 normal participants was assessed using EIM, strength and endurance testing, and clinical assessment.
  
  
  RESULTS
  Tongue musculature in the ALS group was characterized by significantly smaller phase (Ph) and greater resistance (R) when compared with the healthy cohort. Ph and tongue endurance were correlated in the ALS group.
  
  
  CONCLUSIONS
  EIM of tongue musculature could distinguish those with ALS from healthy controls. The demonstrated relationship between tongue function and Ph supports further testing of EIM of the tongue as a potential biomarker in ALS.
authors.affiliation: Department of Speech-Language Pathology, University of Toronto, Toronto, Canada.
authors.forename: Sanjana
authors.initials: S
authors.lastname: Shellikeri
authors.affiliation: Department of Speech-Language Pathology, University of Toronto, Toronto, Canada.
authors.forename: Yana
authors.initials: Y
authors.lastname: Yunusova
authors.affiliation: MGH Institute of Health Professions, Boston, Massachusetts, USA.
authors.forename: Jordan R
authors.initials: JR
authors.lastname: Green
authors.affiliation: Munroe-Meyer Institute, Nebraska Medical Center, Omaha, Nebraska, USA.
authors.forename: Gary L
authors.initials: GL
authors.lastname: Pattee
authors.affiliation: Department of Neurology, MDA ALS Clinic, Massachusetts General Hospital, Boston, Massachusetts, USA.
authors.forename: James D
authors.initials: JD
authors.lastname: Berry
authors.affiliation: Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
authors.forename: Seward B
authors.initials: SB
authors.lastname: Rutkove
authors.affiliation: ALS/MND Clinic, Sunnybrook Health Sciences Centre, Department of Neurology, University of Toronto, Toronto, Canada.
authors.forename: Lorne
authors.initials: L
authors.lastname: Zinman
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology* / Q000503:physiopathology*; D000704:Analysis of Variance; D017097:Electric Impedance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000473:pathology*; D009213:Myography / Q000379:methods; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014059:Tongue / Q000473:pathology* / Q000503:physiopathology
keywords: amyotrophic lateral sclerosis; bulbar dysfunction; electrical impedance myography; motor neuron disease; tongue musculature