Modeling the impact of soft tissue on axial transmission measurements of ultrasonic guided waves in human radius.
Recent in vitro and simulation studies have shown that guided waves measured at low ultrasound frequencies (f=200 kHz) can characterize both material properties and geometry of the cortical bone wall. In particular, a method for an accurate cortical thickness estimation from ultrasound velocity data has been presented. The clinical application remains, however, a challenge as the impact of a layer of soft tissue on top of the bone is not yet well established, and this layer is expected to affect the dispersion and relative intensities of guided modes. The present study is focused on the theoretical modeling of the impact of an overlying soft tissue. A semianalytical method and finite-difference time domain simulations were used. The models developed were shown to predict consistently real in vivo data on human radii. As a conclusion, clinical guided wave data are not consistent with in vitro data or related in vitro models, but use of an adequate in vivo model, such as the one introduced here, is necessary. A theoretical model that accounts for the impact of an overlying soft tissue could thus be used in clinical applications.
Moilanen
Petro
P
Department of Physics, University of Jyvaskyla, Jyvaskyla FI-40014, Finland. pemoilan@cc.jyu.fi
Talmant
Maryline
M
Kilappa
Vantte
V
Nicholson
Patrick
P
Cheng
Sulin
S
Timonen
Jussi
J
Laugier
Pascal
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003198:Computer Simulation; D003238:Connective Tissue / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009038:Motion; D009716:Numerical Analysis, Computer-Assisted; D011884:Radius / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D013997:Time Factors; D014463:Ultrasonography; D055815:Young Adult