title: Magnetic resonance imaging measurement reproducibility for calf muscle and adipose tissue volume.
abstract: OBJECTIVE
  To describe a new semiautomated method for segmenting and measuring the volume of the muscle, bone, and adipose (subcutaneous and intermuscular) tissue in calf muscle compartments using magnetic resonance (MR) images and determine the intrarater and interrater reproducibility of the measures.
  
  
  METHODS
  Proton-density weighted MR images were acquired from the right calf of 21 subjects. Three raters segmented and measured the volumes of bones, adipose tissue, and five individual muscle compartments. Two raters repeated the segmentations. The intra- and interrater reproducibility of the measures (intraclass correlation coefficients; ICC) were determined using generalizability theory.
  
  
  RESULTS
  All ICC values were greater than 0.96. The average standard error of the mean (SEM) of all measures was 1.21 cm(3) and none were greater than 2.3 cm(3) . Essentially all variation (≥97% for all measures) was due to subject differences, indicating low error in the measurements.
  
  
  CONCLUSIONS
  The volumetric measurements for the bones, adipose tissue, and muscle in each of the compartments using MRI were highly reproducible. MRI can provide quantitative, reproducible volumetric measures of bone, adipose tissue, and individual muscle compartments in the calf. We believe these methods can be used to quantify specific muscle or adipose volumetric measures for other clinical or research purposes.
authors.affiliation: Electronic Radiology Laboratory, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, Missouri, USA. commeanp@mir.wustl.edu
authors.forename: Paul K
authors.initials: PK
authors.lastname: Commean
authors.forename: Lori J
authors.initials: LJ
authors.lastname: Tuttle
authors.forename: Mary K
authors.initials: MK
authors.lastname: Hastings
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Strube
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mueller
mesh_terms: D000273:Adipose Tissue / Q000033:anatomy & histology*; D001842:Bone and Bones / Q000033:anatomy & histology; D005260:Female; D006801:Humans; D007866:Leg; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology*; D009929:Organ Size; D015203:Reproducibility of Results