Axial strain calculation using a low-pass digital differentiator in ultrasound elastography.
In ultrasound elastography, tissue axial strains are calculated from the gradient of the estimated axial displacements. However, the common differentiation operation amplifies the noises in the displacement estimation, especially at high frequencies. In this paper, a low-pass digital differentiator (LPDD) is proposed to calculate the axial strain from the estimated tissue displacement. Several LPDDs that have been well developed in the field of digital signal processing are presented. The corresponding performances are compared qualitatively and quantitatively in computer simulations and in preliminary phantom and in vitro experiments. The results are consistent with the theoretical analysis of the LPDDs.
Luo
Jianwen
J
Department of Biomedical Engineering, Tsinghua University, Beijing 100084, PR China. deabj@tsinghua.edu.cn
Bai
Jing
J
He
Ping
P
Ying
Kui
K
D000465:Algorithms; D000818:Animals; D002056:Burns / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002417:Cattle; D004548:Elasticity; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D066298:In Vitro Techniques; D008099:Liver / Q000000981:diagnostic imaging / Q000293:injuries / Q000503:physiopathology; D008107:Liver Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D009716:Numerical Analysis, Computer-Assisted; D019047:Phantoms, Imaging; D012815:Signal Processing, Computer-Assisted; D013314:Stress, Mechanical; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*