Evaluation of cartilage repair tissue after biomaterial implantation in rat patella by using T2 mapping

摘要: To evaluate the ability of MR T2 mapping (8.5 T) to characterize ex vivo longitudinally, morphologically and quantitatively, alginate-based tissue engineering in a rat model patellar cartilage chondral focal defect. Calibrated defects (1.3 mm) were created at day 0 (D0) alginate sponge with (Sp/C+) or without (Sp/C−) autologous chondrocytes implanted. Animals sacrificed sequentially D20, D40 D60 after surgery dissected patellae underwent MRI exploration T). values calculated from eight SE images by using nonlinear least-squares curve fitting on pixel-by-pixel basis (constant repetition time 1.5 s, different echo times: 5.5, 7.5, 10.5, 12.5, 15.0, 20.0, 25.0 30.0 ms). On map, acquired transversal plane through repair zone, global zonal variation evaluated versus control group compared macroscopic score histological studies (toluidine blue, sirius red hematoxylin-eosin). “Partial”, “total” “hypertrophic” patterns identified. At D60, Sp/C+ was characterized higher proportion comparison Sp/C− group. two fold As confirmed histologically, map also permitted distinction three types tissue: “total”, “partial” “hypertrophic”. “Total” high normal (p<0.05). Zonal variation, reflecting collagen network organization, appeared only for “Hypertrophic” tissue, mainly observed presented depth. These results confirm potency macroscopically microscopically scaffold guided-tissue lesion patella (“total”, “hypertrophic”). parameters (i.e. pattern, values) permit as virtual biopsy.