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Dynamic and quantitative assessment of blood coagulation using optical coherence elastography.

Xu X, Zhu J, Chen Z - Sci Rep (2016)

Bottom Line: In this system, acoustic radiation force (ARF) is produced by a remote ultrasonic transducer, and a shear wave induced by ARF excitation is detected by the optical coherence tomography (OCT) system.During porcine whole blood coagulation, changes in the elastic property of the clots increase the shear modulus of the sample, altering the propagating velocity of the shear wave.The results show that the ARFOE-OCE is sensitive to the clot formation kinetics and can differentiate the elastic properties of the recalcified porcine whole blood, blood added with kaolin as an activator, and blood spiked with fibrinogen.

View Article: PubMed Central - PubMed

Affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China.

ABSTRACT
Reliable clot diagnostic systems are needed for directing treatment in a broad spectrum of cardiovascular diseases and coagulopathy. Here, we report on non-contact measurement of elastic modulus for dynamic and quantitative assessment of whole blood coagulation using acoustic radiation force orthogonal excitation optical coherence elastography (ARFOE-OCE). In this system, acoustic radiation force (ARF) is produced by a remote ultrasonic transducer, and a shear wave induced by ARF excitation is detected by the optical coherence tomography (OCT) system. During porcine whole blood coagulation, changes in the elastic property of the clots increase the shear modulus of the sample, altering the propagating velocity of the shear wave. Consequently, dynamic blood coagulation status can be measured quantitatively by relating the velocity of the shear wave with clinically relevant coagulation metrics, including reaction time, clot formation kinetics and maximum shear modulus. The results show that the ARFOE-OCE is sensitive to the clot formation kinetics and can differentiate the elastic properties of the recalcified porcine whole blood, blood added with kaolin as an activator, and blood spiked with fibrinogen.

No MeSH data available.


Related in: MedlinePlus

Analysis of the shear wave during blood coagulation.(a) The measured occurrence time of the shear wave at the wave detection point. Three ARF focus positions are applied for the measurement. (b) The calculated shear wave velocity during blood coagulation. The increase of the shear wave velocity indicates the blood clot becoming stiffer. (c) The shear modulus during blood coagulation. The shear modulus increases rapidly during the early stage of blood coagulation and becomes stable after 30 min. (d) Relation between the shear wave velocity and the shear wave occurrence time at the wave detection point with the lower ARF focus excitation.
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f2: Analysis of the shear wave during blood coagulation.(a) The measured occurrence time of the shear wave at the wave detection point. Three ARF focus positions are applied for the measurement. (b) The calculated shear wave velocity during blood coagulation. The increase of the shear wave velocity indicates the blood clot becoming stiffer. (c) The shear modulus during blood coagulation. The shear modulus increases rapidly during the early stage of blood coagulation and becomes stable after 30 min. (d) Relation between the shear wave velocity and the shear wave occurrence time at the wave detection point with the lower ARF focus excitation.

Mentions: We determine the reaction time by detecting the vibration occurrence after the Doppler variance value is 0.025 a.u. larger than the background for the detected peak. The measured occurrence time of the shear wave is shown in Fig. 2a. When the ARF focus is move downward at a spacing of 1 mm (that is, the ARF focus is moved away from the wave detection point), the wave occurrence time is delayed. The average shear wave velocity can be calculated by the distance of two ARF focus positions and the time difference of wave occurrence. The calculated shear wave velocities during 60 min are shown in Fig. 2b, which are measured by the application of the upper ARF focus and lower ARF focus. The density of the porcine blood clot changes slightly during the measurement so an average density ρ of 1060 kg/m3 is used in Eq. 1. The shear moduli during porcine whole blood coagulation are calculated by Eq. 1, as shown in Fig. 2c. The shear modulus increases rapidly during the early stage of blood coagulation and gradually reaches a plateau after 30 min. The shear modulus of the clotted blood at 46 min is 1.20 kPa from Fig. 2c, which is close to the value 1.39 kPa measured by the MTS Synergie 100 mechanical test. Figure 2d reveals a relation between the shear wave velocity V and the occurrence time of the shear wave at the wave detection point with the lower ARF focus excitation, which can also be described by the following equation:


Dynamic and quantitative assessment of blood coagulation using optical coherence elastography.

Xu X, Zhu J, Chen Z - Sci Rep (2016)

Analysis of the shear wave during blood coagulation.(a) The measured occurrence time of the shear wave at the wave detection point. Three ARF focus positions are applied for the measurement. (b) The calculated shear wave velocity during blood coagulation. The increase of the shear wave velocity indicates the blood clot becoming stiffer. (c) The shear modulus during blood coagulation. The shear modulus increases rapidly during the early stage of blood coagulation and becomes stable after 30 min. (d) Relation between the shear wave velocity and the shear wave occurrence time at the wave detection point with the lower ARF focus excitation.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4836302&req=5

f2: Analysis of the shear wave during blood coagulation.(a) The measured occurrence time of the shear wave at the wave detection point. Three ARF focus positions are applied for the measurement. (b) The calculated shear wave velocity during blood coagulation. The increase of the shear wave velocity indicates the blood clot becoming stiffer. (c) The shear modulus during blood coagulation. The shear modulus increases rapidly during the early stage of blood coagulation and becomes stable after 30 min. (d) Relation between the shear wave velocity and the shear wave occurrence time at the wave detection point with the lower ARF focus excitation.
Mentions: We determine the reaction time by detecting the vibration occurrence after the Doppler variance value is 0.025 a.u. larger than the background for the detected peak. The measured occurrence time of the shear wave is shown in Fig. 2a. When the ARF focus is move downward at a spacing of 1 mm (that is, the ARF focus is moved away from the wave detection point), the wave occurrence time is delayed. The average shear wave velocity can be calculated by the distance of two ARF focus positions and the time difference of wave occurrence. The calculated shear wave velocities during 60 min are shown in Fig. 2b, which are measured by the application of the upper ARF focus and lower ARF focus. The density of the porcine blood clot changes slightly during the measurement so an average density ρ of 1060 kg/m3 is used in Eq. 1. The shear moduli during porcine whole blood coagulation are calculated by Eq. 1, as shown in Fig. 2c. The shear modulus increases rapidly during the early stage of blood coagulation and gradually reaches a plateau after 30 min. The shear modulus of the clotted blood at 46 min is 1.20 kPa from Fig. 2c, which is close to the value 1.39 kPa measured by the MTS Synergie 100 mechanical test. Figure 2d reveals a relation between the shear wave velocity V and the occurrence time of the shear wave at the wave detection point with the lower ARF focus excitation, which can also be described by the following equation:

Bottom Line: In this system, acoustic radiation force (ARF) is produced by a remote ultrasonic transducer, and a shear wave induced by ARF excitation is detected by the optical coherence tomography (OCT) system.During porcine whole blood coagulation, changes in the elastic property of the clots increase the shear modulus of the sample, altering the propagating velocity of the shear wave.The results show that the ARFOE-OCE is sensitive to the clot formation kinetics and can differentiate the elastic properties of the recalcified porcine whole blood, blood added with kaolin as an activator, and blood spiked with fibrinogen.

View Article: PubMed Central - PubMed

Affiliation: College of Life Sciences, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China.

ABSTRACT
Reliable clot diagnostic systems are needed for directing treatment in a broad spectrum of cardiovascular diseases and coagulopathy. Here, we report on non-contact measurement of elastic modulus for dynamic and quantitative assessment of whole blood coagulation using acoustic radiation force orthogonal excitation optical coherence elastography (ARFOE-OCE). In this system, acoustic radiation force (ARF) is produced by a remote ultrasonic transducer, and a shear wave induced by ARF excitation is detected by the optical coherence tomography (OCT) system. During porcine whole blood coagulation, changes in the elastic property of the clots increase the shear modulus of the sample, altering the propagating velocity of the shear wave. Consequently, dynamic blood coagulation status can be measured quantitatively by relating the velocity of the shear wave with clinically relevant coagulation metrics, including reaction time, clot formation kinetics and maximum shear modulus. The results show that the ARFOE-OCE is sensitive to the clot formation kinetics and can differentiate the elastic properties of the recalcified porcine whole blood, blood added with kaolin as an activator, and blood spiked with fibrinogen.

No MeSH data available.


Related in: MedlinePlus