1. All QIBA PHANTOMS C52 Transducer held in ring stand – verasonics system Phantom on turntable – 8 rotation angles 7 transducer locations 3 focal depths (40, 60, 80 mm) SWS estimates: –Bandpass filter 100-1000 Hz –Ransac algorithm – fov ~ 2 cmx2cm –Error bars mean +/- 1 std. dev from 56 measures

2. Results 1786-X 1787-X 40 60 80

3. Sim Results – Lateral Regression Window Location Window positions Blue 0-12 mm Red 1-12 Green 2-12 Black 4-12 Conclusion – you must be outside the ROE (near field of shear wave) to get consistent speeds Also- depth dependence here was within numerical error???