#Epic meaning in cs trial
In trial scans, the Hexabrix concentration was varied until a bimodal distribution of attenuation values was consistently obtained to distinguish cartilage from bone and to determine the average attenuation value of the cartilage. Histograms of the attenuation values were obtained.
#Epic meaning in cs software
The manufacturer’s software was used to contour the intervening slices using the morphing function. The images were manually contoured every 8–10 slices to isolate a region of interest (ROI) containing the subchondral bone plate, cartilage and the scanning medium (air). Finally, we used EPIC-♜T to quantify murine distal femur AC morphology and composition in two mouse models.įor each scan, approximately 500 images were reconstructed. We then compared findings of the new method with established histological and biochemical methods. We first addressed the technical issues of contrast agent concentration, time to reach equilibrium, method of tissue preservation, and repeatability.
The purpose of the present study was to validate the EPIC-♜T method for the study of mouse AC. Bovine cartilage examined by EPIC-♜T has exhibited good correlations between attenuation values and cartilage GAG content 12, 13, 17– 19. EPIC-♜T has been used in small animal models, including AC visualization in rabbits using both cationic 12, 13 and anionic 10 contrast agents and in rat models to assess femoral AC morphology 14, and to quantify CS-glycosaminoglycan (GAG) content 15, 16. AC has an average thickness of 30 to 50 µm in the mouse knee joint 9, precluding the use of some other 3D imaging modalities such as magnetic resonance imaging 11. Thus, this method could be particularly useful for evaluation of murine AC in joint disease models where lesions can be focal and site-specific 9. Briefly, when an anionic contrast agent, such as ioxaglate, diffuses into the AC, it is repelled by the anionic charge of the aggrecan CS, resulting in a non-homogenous distribution of the resulting x-ray attenuation values so that AC thickness and volume and CS content and distribution can be assessed 10.ĮPIC-♜T has the potential to provide both quantitative and spatial distribution data for CS-aggrecan and cartilage morphology. Here, we extend the methods available for CS and morphological quantitation in murine cartilages by validating and applying EPIC- ♜T.
Whereas histological scoring of the cartilage has been widely used 7, 8, the need to generate more global measures of murine joint pathology has led to the use of whole joint and mixed modality imaging 7, 9 and fluorescence-assisted carbohydrate electrophoresis (FACE) 7. Mouse models have become an essential tool to study cartilage degeneration mechanisms in OA 2– 7. Together with other minor proteoglycan (PG) and protein components, the collagens and chondroitin sulfate (CS)-substituted aggrecan complexes provide the biomechanical properties required for weight bearing 1. Articular cartilage (AC) is an extracellular matrix-rich tissue composed of a tensile network of collagens embedded in a reversibly compressible polyanionic gel.
0 kommentar(er)
