Nieminen, H. J.Gahunia, H. K.Pritzker, K. P. H.Ylitalo, T.Rieppo, L.Karhula, S. S.Lehenkari, P.Haeggstörm, E.Saarakkala, S.2018-01-262018-01-262017-10Nieminen, H J, Gahunia, H K, Pritzker, K P H, Ylitalo, T, Rieppo, L, Karhula, S S, Lehenkari, P, Haeggstörm, E & Saarakkala, S 2017, '3D histopathological grading of osteochondral tissue using contrast-enhanced micro-computed tomography', Osteoarthritis and Cartilage, vol. 25, no. 10, pp. 1680-1689. https://doi.org/10.1016/j.joca.2017.05.021http://hdl.handle.net/10138/231637Objective: Histopathological grading of osteochondral (OC) tissue is widely used in osteoarthritis (OA) research, and it is relatively common in post-surgery in vitro diagnostics. However, relying on thin tissue section, this approach includes a number of limitations, such as: (1) destructiveness, (2) sample processing artefacts, (3 ) 2D section does not represent spatial 3D structure and composition of the tissue, and (4) the final outcome is subjective. To overcome these limitations, we recently developed a contrast-enhanced mu CT (CE mu CT) imaging technique to visualize the collagenous extracellular matrix (ECM) of articular cartilage (AC). In the present study, we demonstrate that histopathological scoring of OC tissue from CE mu CT is feasible. Moreover, we establish a new, semi-quantitative OA mu CT grading system for OC tissue. Results: Pathological features were clearly visualized in AC and subchondral bone (SB) with mu CT and verified with histology, as demonstrated with image atlases. Comparison of histopathological grades (OARSI or severity (0-3)) across the characterization approaches, CE mu CT and histology, excellent (0.92, 95% CI = [0.84, 0.96], n = 30) or fair (0.50, 95% CI = [0.16, 0.74], n = 27) intra-class correlations (ICC), respectively. A new mu CT grading system was successfully established which achieved an excellent cross-method (mu CT vs histology) reader-to-reader intra-class correlation (0.78, 95% CI = [0.58, 0.89], n = 27). Conclusions: We demonstrated that histopathological information relevant to OA can reliably be obtained from CE mu CT images. This new grading system could be used as a reference for 3D imaging and analysis techniques intended for volumetric evaluation of OA pathology in research and clinical applications. (C) 2017 Published by Elsevier Ltd on behalf of Osteoarthritis Research Society International.10engcc_by_nc_ndinfo:eu-repo/semantics/openAccessMicro-computed tomographyImagingOsteoarthritisHistologyPathologyAUTOGENOUS PERIOSTEAL GRAFTSCONTINUOUS PASSIVE MOTIONFULL-THICKNESS DEFECTSARTICULAR-CARTILAGE3-DIMENSIONAL MORPHOLOGYJOINT SURFACESOSTEOARTHRITISSHRINKAGEFIXATIONREPAIRMedical biotechnologyPhysical sciencesArticleopenAccessb2f0f0be-4479-4916-827b-c5cf04fcd2c685021924308000410974900014