SBIR-STTR Award

The investigators propose to test the feasibility of developing a three-dimensional method for quantitative X-ray computed tomographic measurement of osteoporosis and its long term progression under treatment, as further described by their abstract: "The large and increasing number of women being treated for osteoporosis underscores the benefit of rapid determination of therapy efficacy. To address this need, we will develop a precise 3D quantitative computed tomography (QCT) technique to quantify the density of the highly-responsive trabecular bone in the spine and hip. We will accomplish this by (i) by developing automated techniques to delineate trabecular and cortical regions of interest based on anatomic landmarks in the 3D images and (ii) by addressing a key source of error associated with variations in coupling between the calibration reference phantom and patient. In Phase I, we will perform two tasks. First, we will implement and evaluate for commercial feasibility three algorithms for analysis of volumetric QCT images, comparing them to each other and to the standard 2D technique. Second, we will measure in vitro the magnitude of the precision error associated with clinically-observed variations in phantom-patient coupling. We will determine whether improving the coupling reduces precision errors. In Phase II, we will commercially develop the algorithm shown to have best performance. If the results of the coupling measurements show a measurable effect on precision error, we will build and evaluate a phantom designed to improve patient phantom coupling."

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.

Thesaurus Terms:
bone imaging /visualization /scanning, computed axial tomography, diagnosis quality /standard, image processing, osteoporosis, patient monitoring device, prognosis alendronate, bone density, computer program /software, hip, parathyroid hormone, pathologic process, spine bioimaging /biomedical imaging, clinical research, human subject, phantom model