Affiliations: Department of Biomedical Engineering, Kyung Hee
University, Yongin-si, Korea
Note: [] Corresponding author: Soo Y. Lee, Department of Biomedical
Engineering, Kyung Hee University, 1 Seochun, Yongin-si, Gyeonggi-do 446-701,
Korea. Tel.: +82 31 201 2980; Fax: +82 31 201 3666; E-mail: sylee01@khu.ac.kr
Abstract: In tissue elasticity imaging, measuring the strain tensor components
is necessary to solve the inverse problem. However, it is impractical to
measure all the tensor components in ultrasound or MRI elastography because of
their anisotropic spatial resolution. The objective of this study is to compute
3D strain tensor maps from the 3D CT images of a tissue-mimicking phantom. We
took 3D micro-CT images of the phantom twice with applying two different
mechanical compressions to it. Applying the 3D image correlation technique to
the CT images under different compression, we computed 3D displacement vectors
and strain tensors at every pixel. To evaluate the accuracy of the strain
tensor maps, we made a 3D FEM model of the phantom, and we computed strain
tensor maps through FEM simulation. Experimentally obtained strain tensor maps
showed similar patterns to the FEM-simulated ones in visual inspection. The
correlation between the strain tensor maps obtained from the experiment and the
FEM simulation ranges from 0.03 to 0.93. Even though the strain tensor maps
suffer from high level noise, we expect the x-ray strain tensor imaging may
find some biomedical applications such as malignant tissue characterization and
stress analysis inside the tissues.
