title: Magnetic resonance imaging of the pulleys of the flexor tendons of the toes at 11.7 T.
abstract: OBJECTIVE
  We obtained high-resolution 11.7-T MR images of the pulleys of the flexor tendons in cadaveric toe specimens. A detailed understanding of toe pulley anatomy as seen with MR is likely to be of benefit in recognizing disease and the effects of trauma.
  
  
  METHODS
  Six cadaveric toes were imaged with an 11.7-T small-bore MR imaging system using optimized coils. Two-dimensional dual-echo SE scans were obtained in three planes (40 × 40 × 400-μm(3) voxel size, TE = 7/14 ms, TR = 3,500 ms, fat saturation). Three-dimensional spoiled gradient echo scans were obtained (90-150 μm(3) isotropic voxel size, TE = 6 ms, TR = 25 ms, with and without fat saturation). Specimen orientation was with the long axis of the toe either parallel or perpendicular to B0.
  
  
  RESULTS
  All the annular (A) pulleys were demonstrated in the great and lesser toes. The A2 pulley in the great and lesser toes and the A4 pulley in the lesser toes were the most substantial pulleys. The A5 pulley, which has not previously been described in the toes, was demonstrated. The cruciform pulleys were also seen and were smaller and thinner. Three tissue layers were seen, and there was evidence of different fiber directions in annular pulleys producing different magic angle effects.
  
  
  CONCLUSIONS
  Detailed anatomy of the pulley system of the flexor tendons was seen on the 11.7-T MR images showing new features and providing a basis for image interpretation. Similarities and differences between the pulley systems in the toes and the fingers were identified.
authors.affiliation: Department of Radiology, University of California, San Diego, School of Medicine, 408 Dickinson St., San Diego, CA, 92103-8226, USA, motafur@gmail.com.
authors.forename: Monica
authors.initials: M
authors.lastname: Tafur
authors.forename: Kenyu
authors.initials: K
authors.lastname: Iwasaki
authors.forename: Sheronda
authors.initials: S
authors.lastname: Statum
authors.forename: Christine B
authors.initials: CB
authors.lastname: Chung
authors.forename: Nikolaus M
authors.initials: NM
authors.lastname: Szeverenyi
authors.forename: Graeme M
authors.initials: GM
authors.lastname: Bydder
mesh_terms: D002102:Cadaver; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008953:Models, Anatomic; D056888:Patient Positioning / Q000379:methods*; D013710:Tendons / Q000033:anatomy & histology*; D014034:Toes / Q000033:anatomy & histology*