TY - GEN
T1 - Error analysis of axial displacement estimation in elasticity imaging
AU - Huang, Sheng Wen
AU - Rubin, Jonathan M.
AU - Jia, Congxian
AU - Olafsson, Ragnar
AU - Witte, Russell S.
AU - O'Donnell, Matthew
PY - 2007
Y1 - 2007
N2 - Correlation-based speckle tracking methods are commonly used in elasticity imaging to estimate displacements. In the presence of local strain, a larger window size (in cross correlation calculation) results in larger displacement error. To reduce tracking error, we proposed using a short window followed by a correlation coefficient filter. Although simulation and experimental results demonstrated the efficacy of the method, it is not clear why correlation filtering reduces tracking error. In this study, we addressed this issue and analyzed the relationship between displacement error and tracking parameters such as window size and filter size. For simplicity, we focused on axial displacement estimation. Analytic forms for tracking without and with correlation filtering were derived to predict tracking error. For the former case, the expression shows increase of error with resolution. For the latter case, there exists one extra negative term so that tracking error decreases with resolution. Furthermore, given a fixed resolution, a smaller window together with a larger filter is preferred. Simulations were performed and the results match the theory well for strains up to 4%.
AB - Correlation-based speckle tracking methods are commonly used in elasticity imaging to estimate displacements. In the presence of local strain, a larger window size (in cross correlation calculation) results in larger displacement error. To reduce tracking error, we proposed using a short window followed by a correlation coefficient filter. Although simulation and experimental results demonstrated the efficacy of the method, it is not clear why correlation filtering reduces tracking error. In this study, we addressed this issue and analyzed the relationship between displacement error and tracking parameters such as window size and filter size. For simplicity, we focused on axial displacement estimation. Analytic forms for tracking without and with correlation filtering were derived to predict tracking error. For the former case, the expression shows increase of error with resolution. For the latter case, there exists one extra negative term so that tracking error decreases with resolution. Furthermore, given a fixed resolution, a smaller window together with a larger filter is preferred. Simulations were performed and the results match the theory well for strains up to 4%.
KW - Correlation filtering
KW - Displacement estimation
KW - Elasticity imaging
KW - Error analysis
KW - Speckle tracking
UR - http://www.scopus.com/inward/record.url?scp=48149084106&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=48149084106&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2007.495
DO - 10.1109/ULTSYM.2007.495
M3 - Conference contribution
AN - SCOPUS:48149084106
SN - 1424413834
SN - 9781424413836
T3 - Proceedings - IEEE Ultrasonics Symposium
SP - 1969
EP - 1972
BT - 2007 IEEE Ultrasonics Symposium Proceedings, IUS
T2 - 2007 IEEE Ultrasonics Symposium, IUS
Y2 - 28 October 2007 through 31 October 2007
ER -