Light Sheet Microscopy for Imaging Cellular Features of Unstained Tissue

Abstract

The incidence of anal cancer has been increasing, with an average annual increase of2.2% over 2010–2019. Anal cancer is predominantly related to Human Papillomavirus (HPV) infections. Recent studies have demonstrated the effectiveness of treating precancer in reducing the risk of anal cancer, highlighting the importance of early detection. However, high-resolution anoscopy (HRA), the current standard for anal cancer screening, has a steep learning curve and lacks widespread availability of skilled practitioners. Additionally, HRA-guided anal biopsies are associated with discomfort and potential complications for patients. Scattering-based light sheet microscopy (sLSM) is an imaging technology capable ofimaging unstained tissues with high resolution and a large field of view (FOV). This dissertation explores the potential of sLSM as an in vivo microscopy modality for enhancing anal cancer screening protocols. Through preliminary studies, we have laid the foundational research necessary for the development of sLSM in clinical settings. These investigations have focused on four topics: 1) optimizing the wavelength for sLSM imaging, 2) developing methods to reduce speckle and shadow artifacts, 3) conducting ex vivo imaging studies on fresh anal tissues with a bench sLSM setup to evaluate the feasibility of diagnosing anal precancer, and 4) developing a compact, handheld sLSM probe.