Light Sheet Reflectance Microscopy

Abstract

Many human diseases are diagnosed by the histopathological analysis of suspicious lesions where cellular morphological changes are examined at microscopic resolution. Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) are two optical imaging technologies that can visualize microscopic details of the tissue without having to remove or process the tissue. However, both RCM and OCT are generally expensive and have either limited field of view or low resolution. Light sheet microscopy, an imaging modality utilizing a thin sheet of light for illumination, can achieve comparable resolution compared to RCM while providing a field of view comparable to OCT. The light sheet microscope can be made at low cost by using a consumer-grade CMOS camera, an inexpensive light source such as an LED, and low-NA objective lenses. In this thesis, we have developed two simple light sheet microscopes with a goal of rapidly visualizing cellular details of the intact tissue either in vivo or ex vivo. The first utilized near-infrared illumination and the second utilized visible illumination. Preliminary imaging results showed that cellular details of the tissue can be visualized over a large field of view in both animal and human tissues.