title: Diffusion tensor imaging can detect the early stages of cartilage damage: a comparison study.
abstract: BACKGROUND
  In the present study, we measured damaged areas of cartilage with diffusion tensor (DT) imaging and T2 mapping, and investigated the extent to which cartilage damage could be determined using these techniques.
  
  
  METHODS
  Forty-one patients underwent arthroscopic knee surgery for osteoarthritis of the knee, a meniscus injury, or an anterior cruciate ligament injury. Preoperative magnetic resonance imaging of the knee was performed, including T2 mapping and diffusion tensor imaging. The presence of cartilage injury involving the medial and lateral femoral condyles and tibia plateau was assessed during surgery using the Outerbridge scale. The ADC, T2 values and fractional anisotropy of areas of cartilage injury were then retrospectively analysed.
  
  
  RESULTS
  The ADC results identified significant differences between Outerbridge grades 0 and 2 (P = 0.041); 0 and 3 (P < 0.001); 1 and 2 (P = 0.045); 1 and 3 (P < 0.001); and 2 and 3 (P = 0.028). The FA results identified significant differences between grades 0 and 1 (P < 0.001); 0 and 2 (P < 0.001); and 0 and 3 (P < 0.001). T2 mapping identified significant differences between Outerbridge grades 0 and 2 (P = 0.032); 0 and 3 (P < 0.001); 1 and 3 (P < 0.001); and 2 and 3 (P < 0.001). Both the T2 mapping (R(2) = 0.7883) and the ADC (R(2) = 0.9184) correlated significantly with the Outerbridge grade. The FA (R(2) = 0.6616) correlated slightly with the Outerbridge grade.
  
  
  CONCLUSIONS
  T2 mapping can be useful for detecting moderate or severe cartilage damage, and the ADC can be used to detect early stage cartilage damage. The FA can also distinguish normal from damaged cartilage.
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. taku115@is.icc.u-tokai.ac.jp.
authors.forename: Taku
authors.initials: T
authors.lastname: Ukai
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. sato-m@is.icc.u-tokai.ac.jp.
authors.forename: Masato
authors.initials: M
authors.lastname: Sato
authors.affiliation: Department of Radiology, Specialized Clinical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. tomyam999@gmail.com.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Yamashita
authors.affiliation: Department of Radiology, Specialized Clinical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. imaiy@is.icc.u-tokai.ac.jp.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imai
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. genya@syd.odn.ne.jp.
authors.forename: Genya
authors.initials: G
authors.lastname: Mitani
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. t-tom8@pc4.so-net.ne.jp.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Takagaki
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. serigano@is.icc.u-tokai.ac.jp.
authors.forename: Kenji
authors.initials: K
authors.lastname: Serigano
authors.affiliation: Department of Orthopaedic Surgery, Surgical Science, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa, 259-1193, Japan. jomo@is.icc.u-tokai.ac.jp.
authors.forename: Joji
authors.initials: J
authors.lastname: Mochida
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001182:Arthroscopy; D002356:Cartilage / Q000473:pathology* / Q000601:surgery; D002357:Cartilage Diseases / Q000473:pathology* / Q000601:surgery; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000473:pathology* / Q000601:surgery; D007719:Knee Joint / Q000473:pathology* / Q000601:surgery; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000473:pathology* / Q000601:surgery; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D055815:Young Adult