| Biography | |
|---|---|
 Prof. In Gwun Jang Korea Advanced Institute of Science and Technology, Republic of Korea |
|
| Title: Topology optimization-based bone remodeling and its application to bone microstructure reconstruction from clinical CT scan data | |
| Abstract: For osteoporosis diagnosis, bone microstructure is considered as the most reliable measure of bone strength. However, there exist significant difficulties in representing in vivo bone microstructure due to the limited spatial resolutions of current clinical imaging devices such as CT and MRI. This study presents a novel method that can reconstruct bone microstructures from CT scan data, using the finite element analysis and topology optimization. For the purpose, topology optimization with a 2-D micro-finite element (FE) model is first conducted to determine a full trabecular architecture in the proximal femur under three loading cases in daily activities. The optimization results show that trabecular architecture can be considered as an optimized structure, which proves the self-optimizing capabilities of bone. As a next step, topology optimization for compliance minimization is performed to reconstruct trabecular microarchitecture in the proximal femur. A constraint for the BMD deviation is involved to maintain the patient-specific spatial bone distribution obtained from the quantitative CT (QCT) scan data. By doing so, the proposed method can enhance the QCT images of a 625m resolution up to those of a 62.5m resolution, which can precisely represent bone microstructure. To validate the proposed method, micro CT scan data of a 78.125m resolution are downscaled to have a 625m resolution. Then, they are upscaled to have an original resolution by using the proposed method. The reconstructed bone microstructure was compared with the reference in terms of image similarity, bone morphometric indices, and bone strength. This reveals a unique feature of anisotropic bone strength which the clinical CT scan data cannot provide. These results indicate that the proposed method can contribute to improving the accuracy of bone strength assessment and, therefore, can be a valuable tool for early osteoporosis diagnosis in the clinical field. | |
| Biography: In Gwun Jang is an associate professor in the Cho Chun Shik Graduate School of Green Transportation, KAIST, Daejeon, South Korea. He received a Ph.D. degree in the Department of Mechanical Engineering from KAIST in 2006. He then worked at Queens University, Kingston, Canada as a postdoctoral fellow. He is currently the head of the Cho Chun Shik Graduate School of Green Transportation, KAIST. He has published 39 peer-reviewed journal papers, 88 conference papers, and 43 patents in total. His expertise covers design optimization ranging from the component level to system level, based on multidisciplinary computational analysis. In particular, his current research interest is to propose a novel method that can conduct patient-specific diagnosis and prognosis for the human skeletal system and to develop the corresponding a medical device. | |
