title: Contrasting echogenicity in flexor digitorum profundus-flexor carpi ulnaris: a diagnostic ultrasound pattern in sporadic inclusion body myositis.
abstract: BACKGROUND
  In this study we aimed to clarify whether muscle ultrasound (US) of the forearm can be used to differentiate between patients with sporadic inclusion body myositis (s-IBM) and those with s-IBM-mimicking diseases.
  
  
  METHODS
  We compared the echo intensity (EI) of the flexor digitorum profundus (FDP) muscle and the flexor carpi ulnaris (FCU) muscles in patients with s-IBM (n = 6), polymyositis/dermatomyositis (PM/DM; n = 6), and amyotrophic lateral sclerosis (ALS; n = 6).
  
  
  RESULTS
  We identified EI abnormalities in 100% of patients with s-IBM, 33% of those with PM/DM, and 33% of those with ALS. An "FDP-FCU echogenicity contrast," a US pattern involving a higher EI in the FDP than in the FCU, was observed in all patients with s-IBM, but in none of those with PM/DM or ALS.
  
  
  CONCLUSIONS
  FDP-FCU echogenicity contrast in muscle US is a sensitive diagnostic indicator of s-IBM.
authors.affiliation: Department of Neurology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kamigyo-ku, Kyoto, 602-0841, Japan.
authors.forename: Yu-Ichi
authors.initials: Y
authors.lastname: Noto
authors.forename: Kensuke
authors.initials: K
authors.lastname: Shiga
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Tsuji
authors.forename: Masaki
authors.initials: M
authors.lastname: Kondo
authors.forename: Takahiko
authors.initials: T
authors.lastname: Tokuda
authors.forename: Toshiki
authors.initials: T
authors.lastname: Mizuno
authors.forename: Masanori
authors.initials: M
authors.lastname: Nakagawa
mesh_terms: D000328:Adult; D000368:Aged; D000690:Amyotrophic Lateral Sclerosis / Q000000981:diagnostic imaging*; D003882:Dermatomyositis / Q000000981:diagnostic imaging*; D003937:Diagnosis, Differential; D005260:Female; D005542:Forearm / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging*; D018979:Myositis, Inclusion Body / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014463:Ultrasonography
keywords: amyotrophic lateral sclerosis; diagnosis; inclusion body myositis; muscle; ultrasound