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3D mapping of elastic modulus using shear wave optical micro-elastography.

ABSTRACT: Elastography provides a powerful tool for histopathological identification and clinical diagnosis based on information from tissue stiffness. Benefiting from high resolution, three-dimensional (3D), and noninvasive optical coherence tomography (OCT), optical micro-elastography has the ability to determine elastic properties with a resolution of ~10??m in a 3D specimen. The shear wave velocity measurement can be used to quantify the elastic modulus. However, in current methods, shear waves are measured near the surface with an interference of surface waves. In this study, we developed acoustic radiation force (ARF) orthogonal excitation optical coherence elastography (ARFOE-OCE) to visualize shear waves in 3D. This method uses acoustic force perpendicular to the OCT beam to excite shear waves in internal specimens and uses Doppler variance method to visualize shear wave propagation in 3D. The measured propagation of shear waves agrees well with the simulation results obtained from finite element analysis (FEA). Orthogonal acoustic excitation allows this method to measure the shear modulus in a deeper specimen which extends the elasticity measurement range beyond the OCT imaging depth. The results show that the ARFOE-OCE system has the ability to noninvasively determine the 3D elastic map.

SUBMITTER: Zhu J

PROVIDER: S-EPMC5071855 | biostudies-other | 2016 Oct

REPOSITORIES: biostudies-other

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3D mapping of elastic modulus using shear wave optical micro-elastography.

Zhu Jiang J Qi Li L Miao Yusi Y Ma Teng T Dai Cuixia C Qu Yueqiao Y He Youmin Y Gao Yiwei Y Zhou Qifa Q Chen Zhongping Z

Scientific reports 20161020

Elastography provides a powerful tool for histopathological identification and clinical diagnosis based on information from tissue stiffness. Benefiting from high resolution, three-dimensional (3D), and noninvasive optical coherence tomography (OCT), optical micro-elastography has the ability to determine elastic properties with a resolution of ~10 μm in a 3D specimen. The shear wave velocity measurement can be used to quantify the elastic modulus. However, in current methods, shear waves are me ...[more]

PMID: 27762276

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Dataset Information

3D mapping of elastic modulus using shear wave optical micro-elastography.

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3D mapping of elastic modulus using shear wave optical micro-elastography.

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