title: Precision and accuracy of computed tomography foot measurements.
abstract: OBJECTIVE
  To test the accuracy and precision of computed tomography (CT) imaging for describing the 3-dimensional structure of the foot in patients with diabetes mellitus and peripheral neuropathy.
  
  
  METHODS
  Experimental, test-retest.
  
  
  METHODS
  Clinical CT scanner at a local hospital.
  
  
  METHODS
  Two tissue-equivalent phantoms and 6 cadaver feet.
  
  
  METHODS
  Measurements taken from CT data of phantoms and cadaver feet were compared with physical (caliper) measurements. The feasibility of creating a computer-aided design/rapid prototyping 3-dimensional model from CT data was assessed by using 1 cadaver foot.
  
  
  RESULTS
  No bias was found for phantom or cadaver CT measurements compared with caliper measurements. The mean difference between repeat scans of cadaver feet (1 observer) was 0.1 +/- 0.8 mm and between observers, 0.4 +/- 0.8 mm. Comparing caliper measurements of the rapid prototype model and actual foot measurements revealed an error of 0.3 +/- 0.4 mm.
  
  
  CONCLUSIONS
  CT-based 3-dimensional imaging produced accurate and precise foot measurements, enabling description of internal and external structures. This capability will be coupled with plantar pressure measurements to improve our understanding and treatment of foot ulcers in people with diabetes.
authors.affiliation: Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA. smithki@mir.wustl.edu
authors.forename: K E
authors.initials: KE
authors.lastname: Smith
authors.forename: P K
authors.initials: PK
authors.lastname: Commean
authors.forename: D D
authors.initials: DD
authors.lastname: Robertson
authors.forename: T
authors.initials: T
authors.lastname: Pilgram
authors.forename: M J
authors.initials: MJ
authors.lastname: Mueller
mesh_terms: D002102:Cadaver; D017719:Diabetic Foot / Q000000981:diagnostic imaging / Q000534:rehabilitation; D005240:Feasibility Studies; D005260:Female; D005528:Foot / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012775:Shoes; D014057:Tomography, X-Ray Computed / Q000592:standards*