Precise 3D QCT to Monitor Osteoporosis Therapy

描述（由申请人提供）：越来越多的女性接受骨质疏松症药物治疗，强调需要敏感的方法来监测治疗。由于定量计算机断层扫描（QCT）可以选择性地评估小梁骨和皮质骨，这两种骨对疾病和治疗的反应可能不同，因此定量计算机断层扫描（QCT）非常适合这一目的。然而，QCT解决治疗或疾病引起的骨密度（BMD）变化的能力受到可变精度误差的限制。这些精度误差主要与当前技术对操作符的依赖有关，这些技术涉及手动切片选择和感兴趣区域放置。在我们的第一阶段授权中，我们通过开发和演示图像配准算法的可行性来解决这个问题，该算法对串行图像进行对齐，并使用由此产生的3D转换将基线区域映射到后续图像的相同体积中。正如我们在第一阶段最终报告中所记载的那样，这种快速和自动化的方法在体内测量脊柱和股骨小梁近端骨密度时的精度误差分别为1.0 mg/cc和0.9 mg/cc。在此应用中，我们建议开发并商业化一个原型软件包，该软件包将诊断3D QCT骨密度测量与我们的新方法相结合，用于高度可重复的纵向测量。

DESCRIPTION (provided by applicant):The growing number of women receiving drug treatment for osteoporosis underscores the need for sensitive methods to monitor therapy. Because it permits selective assessment of the trabecular and cortical bone, which may respond differently to disease and therapy, quantitative computed tomography (QCT) is well-suited to this purpose. However, the ability of QCT to resolve therapy- or disease-induced changes in bone mineral density (BMD) is limited by variable precision errors. These precision errors mostly relate to the operator-dependence of current techniques, which involve manual slice selection and region of interest placement. In our Phase I Grant, we have addressed this problem by developing and demonstrating the feasibility of an image registration algorithm which aligns serial images and uses the resulting 3D transformation to map a baseline region into the same volume of the follow-up image. As we have documented in the Phase I Final Report, this fast and automated approach yields precision errors in vivo of 1.0 mg/cc and 0.9 mg/cc for spinal and proximal femoral trabecular BMD measurements respectively. In this application, we propose to develop and commercialize a prototype software package which will combine diagnostic 3D QCT BMD measurements with our new approach for highly reproducible longitidunal measurements. PROPOSED COMMERCIAL APPLICATION: We will provide commercial CT imaging centers with a powerful set of tools which they can use to compete in the bone mineral density measurement market. The diagnostic measurement component will allow CT scanners to measure bone mineral density in the spine and hip in bone regions comparable to those measured by DXA. Moreover, the high reproducibility of our technique will permit CT centers to offer a method for monitoring therapy effects which will be superior to DXA.