title: Definition of pertinent parameters for the evaluation of articular cartilage repair tissue with high-resolution magnetic resonance imaging.
abstract: To evaluate articular cartilage repair tissue after biological cartilage repair, we propose a new technique of non-invasive, high-resolution magnetic resonance imaging (MRI) and define a new classification system. For the definition of pertinent variables the repair tissue of 45 patients treated with three different techniques for cartilage repair (microfracture, autologous osteochondral transplantation, and autologous chondrocyte transplantation) was analyzed 6 and 12 months after the procedure. High-resolution imaging was obtained with a surface phased array coil placed over the knee compartment of interest and adapted sequences were used on a 1 T MRI scanner. The analysis of the repair tissue included the definition and rating of nine pertinent variables: the degree of filling of the defect, the integration to the border zone, the description of the surface and structure, the signal intensity, the status of the subchondral lamina and subchondral bone, the appearance of adhesions and the presence of synovitis. High-resolution MRI, using a surface phased array coil and specific sequences, can be used on every standard 1 or 1.5 T MRI scanner according to the in-house standard protocols for knee imaging in patients who have had cartilage repair procedures without substantially prolonging the total imaging time. The new classification and grading system allows a subtle description and suitable assessment of the articular cartilage repair tissue.
authors.affiliation: Department of Traumatology, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna, Austria. stefan.marlovits@akh-wien.ac.at
authors.forename: Stefan
authors.initials: S
authors.lastname: Marlovits
authors.forename: Gabriele
authors.initials: G
authors.lastname: Striessnig
authors.forename: Christoph T
authors.initials: CT
authors.lastname: Resinger
authors.forename: Silke M
authors.initials: SM
authors.lastname: Aldrian
authors.forename: Vilmos
authors.initials: V
authors.lastname: Vecsei
authors.forename: Herwig
authors.initials: H
authors.lastname: Imhof
authors.forename: Siegfried
authors.initials: S
authors.lastname: Trattnig
mesh_terms: D000328:Adult; D001182:Arthroscopy; D016025:Bone Transplantation / Q000473:pathology; D002356:Cartilage / Q000637:transplantation; D002358:Cartilage, Articular / Q000473:pathology* / Q000601:surgery; D019902:Chondrocytes / Q000637:transplantation; D005260:Female; D005269:Femur / Q000473:pathology / Q000601:surgery; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007719:Knee Joint / Q000473:pathology / Q000601:surgery; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D013585:Synovitis / Q000175:diagnosis; D000267:Tissue Adhesions / Q000175:diagnosis; D014182:Transplantation, Autologous; D014945:Wound Healing