IMAGING OF AVASCULAR NECROSIS OF FEMORAL HEAD IN SPONTANEOUS HYPERTENSIVE RATS AND ITS EXPERIMENTAL MODEL

我们最初的目的是获得自发性高血压大鼠股骨头缺血坏死的磁共振图像，但由于直径太小，如2 mm，未能成像。因此，我们改变了计划，尝试用显微CT对自发性高血压大鼠股骨头的骨小梁结构进行三维分析。我们在骨小梁结构分析方面取得了一些结果，但遗憾的是，这些结果并不具有进一步研究的前景。我们再次改变了计划，尝试使用来自多探测器CT的数据对人体脊椎的骨小梁结构进行活体三维分析。利用Micro CT内置的骨小梁结构三维分析软件，成功地读取了多层螺旋CT的图像数据。我们利用一具人体身体的脊椎进行了三维分析的精度研究。测量骨体积(BV)、骨表面积(BS)、骨密度(BV/TV)、骨小梁厚度(TB)等三维参数。Th)、小梁间隙(Tb.SP)、骨小梁因子(TBPf)、结构模型指数(SMI)、结节数(N.ND)。我们测量了5次标本，并计算了变异系数(CV)。BV、BS、BV/TV、TB中的简历。TH、TB。SP、TBPf、SMI、N.ND分别为1.8%、0.91%、1.8%、1.4%、1.5%、7.7%、0.81%、2.5%。其结果与双X射线骨密度仪测量结果的精密度相当。提示在体骨小梁结构的三维分析可用于临床评价骨质疏松症药物对骨小梁结构的影响。

We originally aimed to obtain magnetic resonance images of avascular necrosis of femoral head in spontaneous hypertensive rats, however, we failed to image them due to too small size of them such as 2mm in a diameter. Therefore, we change our plan and tried to obtain 3 dimensional analysis of trabecular structure of the femoral heads in spontaneous hypertensive rats using micro computed tomography. We obtained some results for the trabecular structural analysis, but, unfortunately, they were not promising of further study. We, again, changed our plan and tried to perform in vivo three-dimensional analysis of trabecular structure of human vertebra using data from multi-detector CT. We successfully read image data of multi-detector CT using the software for three-dimensional analysis of trabecular structure built in the micro CT. We performed precision study for the three-dimensional analysis using vertebra of a human cadaver. We evaluated three dimensional parameters of bone volume (BV) , bone surface (BS), bone density (BV/TV), trabecular thickness (Tb. Th), trabecular space (Tb. Sp), trabecular bone factor (TBPf) , structure model index (SMI) , number of nodes (N. Nd). We measured the specimens five times and calculated coefficient variation (CV). The CVs in BV, BS, BV/TV, Tb. Th, Tb. Sp, TBPf, SMI, N. Nd were 1.8 %, 0.91 %, 1.8 %, 1.4 %, 1.5 %, 7.7 %, 0.81 %, 2.5 %, respectively. The results were comparable to the precision of bone densitometry by dual x-ray absorptiometry. This suggest that in vivo three dimensional analysis of trabecular bone structure would be used clinically for evaluating effects of drugs for osteoporosis on trabecular bone structure.