Subcellular resolution is required for OCT to portray the microstructural information of myocardium issue that is comparable to histology. Compare with its intrinsic intensity contrast, functional OCT system may provide contrast related to the tissue composition. We present a high-resolution (HR) cross-polarization OCT system that can provide functional contrast of human myocardium tissue in one-shot measurement. The system is implemented based on our previously reported high-resolution long imaging range OCT system with minimal modification. It features a broadband supercontinuum source, single-channel and one-shot detection, with moderate signal processing. The system has an axial resolution of 3.07 μm, and it is capable to produce accurate polarization information by calibrating the reconstruction performance with a quarter wave plate. The orthogonal polarization channels are multiplexed to fit within one imaging range. Following CP-OCT detection, the retardation can be reconstructed based on the complex signals, and the depolarization effect can be depicted by the channel intensity ratio. Tissue specimens from ten fresh human hearts are used to demonstrate the capability of CP-OCT contrasts. By analyzing the intrinsic and functional OCT contrasts of fresh human myocardium tissues against histology slides, we show that various tissue structures and tissue types of the myocardium, such as fibrosis and ablated lesions, can be better depicted by the function contrasts. We also suggest the possibility of using A-line features from the two orthogonal polarization channels to distinguish normal myocardium, fibrotic myocardium, and ablated lesions. This may serve as a rapid and cost-efficient solution for assessment of myocardium and further facilitate automatic tissue classification.
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