Quantification of skeletal growth, modeling, and remodeling by in vivo micro computed tomography

摘要: In this study we established an image analysis scheme for the investigation of cortical and trabecular bone development during skeletal growth tested concept on in vivo μCT images rats. To evaluate its efficacy, applied technique to young (1-month-old) adult (3-month-old) rat tibiae with vehicle (Veh) or intermittent parathyroid hormone (PTH) treatment. By overlaying 2 sequential scans based their distinct microarchitecture, calculated linear rate rats be 0.31 mm/day at proximal tibia. Due rapid (3.7 mm 12 days), scanned region day had no overlap tissue 0. Instead, imaged represented newly generated from plate. The new PTH-treated significantly greater volume fraction, number, thickness than those Veh-treated rats, indicating PTH's anabolic effect modeling. contrast, PTH was found caused by remodeling. tibia also thickened more group (23%) Veh (14%). This primarily driven endosteal formation coalescence into cortex. process can visualized aligning local structural changes using registration. As a result, cortex after treatment 31% less porous, 22% polar moment inertia compared group. Lastly, monitored longitudinal measuring distance flow away tibial plate 3 months 19 age discovered total 3.5mm 16 months. It demonstrated that efficiently growth, modeling, remodeling, is ready translated clinical imaging platform.