Development of Functional Optical Coherence Tomography for Structural and Microangiography Assessment of Heart and Skin

Abstract

This thesis explores the potential of developing functional Optical Coherence Tomography (OCT) for structural and microangiographic applications in heart and skin tissues. As a noninvasive imaging technique, OCT has revolutionized fields such as ophthalmology, cardiology, and dermatology by providing high-resolution visualization of biological structures and microvasculature. However, its capacity to capture physiological characterization, both qualitatively and quantitatively, remains limited. This research aims to bridge that gap by advancing functional OCT techniques to provide novel insights into tissue and vascular behavior in complex vascularized areas like coronary microcirculation and skin. Chapter 1 introduces OCT principles and their clinical significance for noninvasive imaging. Chapter 2 focuses on advanced OCT techniques for assessing microvascular networks and tissue composition. Methods such as Optical Microangiography (OMAG) and OCT velocimetry demonstrate OCT's capability to visualize capillary morphology and blood flow without contrast agents, while quantitatively characterizing hemodynamic properties and microvascular health. Additionally, OCT structural imaging techniques, such as calibrated optical attenuation coefficient (OAC), are presented to differentiate tissue compositions in distinct skin layers based on scattering properties. Chapter 3 applies OCT Angiography (OCTA) to assess microvascular damage in infarcted hearts, uncovering structural and functional changes post-myocardial infarction (MI), such as capillary loss, vessel enlargement, and altered blood flow, offering insights into coronary network remodeling. Chapter 4 investigates OCTA's ability to detect depth-resolved blood flow signals and pulse patterns across different skin layers, showcasing potential applications in non-invasive cardiovascular monitoring. Chapter 5 explores OCT's dermatological applications, including monitoring skin aging, UV-induced changes, and light-tissue interactive behaviors. It highlights OCT's ability to detect subclinical changes—such as vessel dilation, epidermal thickening, and structural organization differences—before clinically visible signs appear, supporting early intervention.