The field X-ray imaging is being revolutionized by the development of techniques based on phase-contrast (PC), which have shown great promise for soft tissue imaging. The principal advantage is that X-ray PC imaging methods are sensitive to alternative physical properties of tissues, and can differentiate tissues that have very similar or even identical X-ray absorption properties. The broad objective of this research program is to develop and comprehensively evaluate X-ray PC imaging and tomography for use in the evaluation and monitoring of engineered tissues. The specific research objects of the project are to: (1) Investigate non-traditional mechanisms of X-ray contrast produced by model-engineered tissues and determine conditions for optimal imaging of polymer and tissue structures ex vivo and in culture conditions; (2) Optimize grating-based PC imager designs and image reconstruction algorithms for volumetric imaging of engineered tissues; and (3) Evaluate a benchtop PC imager for 3D in vivo evaluation of engineered tissues in small animal models. The intellectual merit of the proposed research arises from the development and refinement of hardware designs and image formation algorithms for a new X-ray imaging modality and their application to the important problem of characterizing and monitoring engineered tissues. Novel X-ray contrast mechanisms that can effectively characterize engineered tissues will be systematically investigated. Model polymer scaffolds and engineered tissues will be used in the evaluation and optimization of these imaging systems in order to ensure broad relevance to many areas of tissue engineering, regenerative medicine and biomaterials. To accomplish this research, a combination of physics and fundamental principles of biomedical engineering and imaging science are employed by our collaborative research team.
There are several broad impacts of the project that will yield important benefits to both biomedical science and society. The successful completion of this project will establish X-ray PC imaging as a highly effective tool for characterizing the 3D structure of engineered tissues and will have a transformative impact on the field of tissue engineering. The acceleration of tissue engineering research will have a significant impact on human health by leading to new therapeutic approaches for the treatment of defects resulting from disease, trauma or congenital defects. The integration of this research with the proposed educational activities will help attract students to the increasingly important fields of biomedical engineering, biomedical imaging and tissue engineering and enhance greatly their educational opportunities.
