title: Delayed gadolinium-enhanced MRI of cartilage and T2 mapping for evaluation of reparative cartilage-like tissue after autologous chondrocyte implantation associated with Atelocollagen-based scaffold in the knee.
abstract: OBJECTIVE
  To elucidate the quality of tissue-engineered cartilage after an autologous chondrocyte implantation (ACI) technique with Atelocollagen gel as a scaffold in the knee in the short- to midterm postoperatively, we assessed delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) and T2 mapping and clarified the relationship between T1 and T2 values and clinical results.
  
  
  METHODS
  In this cross-sectional study, T1 and T2 mapping were performed on 11 knees of 8 patients (mean age at ACI, 37.2 years) with a 3.0-T MRI scanner. T1implant and T2implant values were compared with those of the control cartilage region (T1control and T2control). Lysholm scores were also assessed for clinical evaluation. The relationships between the T1 and T2 values and the clinical Lysholm score were also assessed.
  
  
  RESULTS
  There were no significant differences in the T1 values between the T1implant (386.64 ± 101.78 ms) and T1control (375.82 ± 62.89 ms) at the final follow-up. The implants showed significantly longer T2 values compared to the control cartilage (53.83 ± 13.89 vs. 38.21 ± 4.43 ms). The postoperative Lysholm scores were significantly higher than the preoperative scores. A significant correlation was observed between T1implant and clinical outcomes, but not between T2implant and clinical outcomes.
  
  
  CONCLUSIONS
  Third-generation ACI implants might have obtained an almost equivalent glycosaminoglycan concentration compared to the normal cartilage, but they had lower collagen density at least 3 years after transplantation. The T1implant value, but not the T2 value, might be a predictor of clinical outcome after ACI.
authors.affiliation: Department of Orthopaedic Surgery, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan. tadenuma@med.shimane-u.ac.jp.
authors.forename: Taku
authors.initials: T
authors.lastname: Tadenuma
authors.affiliation: Department of Orthopaedic Surgery, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Uchio
authors.affiliation: Department of Orthopaedic Surgery, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Kumahashi
authors.affiliation: Department of Radiology, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan.
authors.forename: Eiji
authors.initials: E
authors.lastname: Fukuba
authors.affiliation: Department of Radiology, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Kitagaki
authors.affiliation: Department of Orthopaedic Surgery, Shimane University School of Medicine, 89-1, Enya-cho, Izumo-shi, Shimane-ken, 693-8501, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Iwasa
authors.affiliation: Department of Orthopaedic Surgery, Integrated Health Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Ochi
mesh_terms: D000293:Adolescent; D000328:Adult; D019902:Chondrocytes / Q000637:transplantation*; D003094:Collagen / Q000737:chemistry*; D003287:Contrast Media / Q000008:administration & dosage; D019544:Equipment Failure Analysis; D005260:Female; D050724:Fractures, Cartilage / Q000000981:diagnostic imaging* / Q000628:therapy*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007718:Knee Injuries / Q000000981:diagnostic imaging / Q000628:therapy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D054457:Tissue Scaffolds; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003287:Contrast Media; C059821:atelocollagen; D003094:Collagen
keywords: Autologous chondrocyte implantation (ACI); Cartilage injury; T2 map; dGEMRIC