Tissue Elasticity Estimation with Optical Coherence Elastography: Toward Mechanical Characterization of In Vivo Soft Tissue

Abstract
High-resolution imaging provides a significant means for accurate material modulus estimation and mechanical characterization. Within the realm of in vivo soft tissue characterization, particularly on small biological length scales such as arterial atherosclerotic plaques, optical coherence tomography (OCT) offers a desirable imaging modality with higher spatial resolution and contrast of tissue as compared with intravascular ultrasound (IVUS). Based on recent advances in OCT imaging and elastography, we present a fully integrated system for tissue elasticity reconstruction, and assess the benefits of OCT on the distribution results of four representative tissue block models. We demonstrate accuracy, with displacement residuals on the order of 10−6 mm (more than 3 orders of magnitude less than average calculated displacements), and high-resolution estimates, with the ability to resolve inclusions of 0.15 mm diameter.