Development of a High Frequency Shear Wave Technique for Detecting the Viscoelastic Properties of Thrombus

• Main Authors: Pei-Yu Chen, 陳培煜
• Other Authors: Kuan-Jen Lin
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/78930642320661420622

碩士 === 輔仁大學 === 電機工程學系碩士班 === 102 === Measurements of the viscoelastic properties of a thrombus can be used to assess whether blood clots are likely to become occlusive or to break apart and leak into the blood circulation and block smaller vessels. An accurate method for estimating both the shear elasticity and viscosity of a blood clot in vivo is still lacking, which prompted us to use a novel shear-wave approach to measure the viscoelastic modulus of blood clots. The frequency dispersion of the shear-wave propagation speed in soft tissue was used to measure both the elasticity and viscosity of blood clots. The experimental system was verified by measuring the viscoelastic modulus of phantoms containing gelatin at different concentrations. Blood-clot experiments were carried out using porcine whole blood with hematocrits ranging from 3% to 40%. The measured values for both clots and gelatin phantoms were compared to those obtained using an embedded-sphere method in order to validate the accuracy of the viscoelastic modulus estimations. The shear elastic modulus increased from 406.9±15.8 (mean±SD) Pa for 3% gelatin to 1587.2±28.9 Pa for 7% gelatin, while the viscosity increased from 0.12±0.02 Pa∙s to 0.86±0.05 Pa∙s, respectively. The shear modulus increased from 196.8±58.4 Pa for 40%-hematocrit clots to 641.4±76.3 Pa for 3%-hematocrit clots, while the viscosity increased from 0.29±0.02 Pa∙s to 0.42±0.01 Pa∙s, respectively. This paper successfully perform the shear wave technique to measure the viscoelastic modulus of thrombus, and all the result is corresponding to previous literature.