Optical coherence elastography (OCE) is emerging as a potentially useful tool in the identification of a number of diseases. In our group, we are developing OCE techniques based on compressive loading. Typically, these techniques employ a quasi-static mechanical load introduced by uniaxially compressing a sample with a rigid plate. The resulting deformation of the sample is measured using phase-sensitive detection and the local axial strain is estimated from the slope of displacement over a finite depth in the sample, providing qualitative mechanical contrast. In this talk, an overview of our work will be given and some of the outstanding challenges described. Our group’s work in OCE can broadly be divided into four streams, each of which will be described in detail in the talk: system development; techniques; quantification; and applications.
• System development: The phase-sensitive OCE method we have developed will be described, as well as a high resolution optical coherence microscopy-based elastography system suitable for imaging cellular-scale mechanical properties.
• Techniques: In addition to presenting techniques to estimate strain, our approaches to imaging tissue viscoelasticity and nonlinearity will be described. A technique to segment elastograms based on strain heterogeneity will be presented.
• Quantification: Methods under development to quantify tissue stiffness in compression OCE will be described. This work is enabled by optical palpation and solutions to the forward and inverse elasticity problems.
• Applications: Three applications areas will be described: intraoperative assessment of tumour margins, mapping stiffness in tumour biology and assessing the stiffness of cardiovascular tissue in an animal model.
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