Development and translation of label-free functional microscopy based on optical coherence tomography

Abstract

Optical coherence tomography (OCT), an imaging modality based on low coherence interferometry, can be extended to obtain various endogenous functional contrasts. This thesis focuses on the development and translation of angiographic and polarization sensitive (PS) OCT techniques for clinical and preclinical applications. This goal includes four specific aims. The first aim is to develop a clinical imaging system to image the anatomy and microvasculature of human skin. The second aim is to develop a high performance post-processing algorithm for angiographic OCT. Towards this aim, we developed a processing algorithm based on complex differential variance (CDV) and confirmed its performance by benchmarking it against other published algorithms. The third aim is to develop a new approach for achieving high spatial resolution with an extended depth of focus for angiographic imaging. To achieve this aim, we have designed and built a triband wavelength system in which each spectrum is tightly focused at displaced focal planes to yield high transverse resolution over an effectively extended depth range. The fourth aim is to provide an imaging platform for preclinical study of peripheral nerve injury and repair. The vascularization is assessed by angiographic OCT, and the degree of myelination is measured by PS-OCT. These results confirm that the OCT platform can reveal new insights into preclinical studies of nerve regeneration and may ultimately provide a means for clinical intraoperative assessment of peripheral nerve health.