Download or read book Optimizing Optical-sectioning Microscopy Techniques for Diverse Biomedical Applications written by Ye Chen and published by . This book was released on 2019 with total page 94 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical-sectioning microscopes are powerful tools that can be used by biomedical scientists and clinicians to visualize and monitor subcellular features in thick tissues at relatively large depths (up to hundreds of microns). In clinical settings, such technologies could play a transformative role in detecting early-stage cancer and guiding the surgical resection of tumors. This dissertation focuses on optimizing optical-sectioning microscopes that utilize off-axis illumination and collection architectures to spatially filter out-of-focus and multiply-scattered photons. In particular, we will focus on overcoming certain challenges with using dual-axis confocal (DAC) microscopy and light-sheet microscopy to image biological specimens, such as mitigating resolution degradation caused by refractive heterogeneities within tissues and achieving rapid microscopic pathology of large clinical specimens. In the case of DAC microscopy, tissue-imaging performance is highly sensitive to the effects of refractive-index heterogeneities within biological specimens, which cause beam steering and distortion artifacts that lead to misalignment of the off-axis illumination and collection beam paths of a DAC microscope. Since the propagation-invariant and self-reconstructing features of Bessel beams have been shown to benefit microscopy of specimens with refractive heterogeneities, Bessel-beam illumination has been explored as a means to alleviate resolution degradation that occurs when performing tissue-imaging with DAC microscopy. Results indicate that DAC microscopy with Bessel illumination exhibits reduced resolution degradation from microscopic tissue heterogeneities compared to DAC microscopy with conventional Gaussian illumination. In the context of light-sheet microscopy, an open-top light-sheet (OTLS) microscope along with a novel fluorescent analog of hematoxylin and eosin (H&E) staining, has been developed and optimized for robust intraoperative pathology of lumpectomy margins. OTLS images of the surfaces of fresh breast samples were compared to gold-standard H&E histological images to showcase that the image quality of OTLS microscopy can approximate that of archival H&E histology of formalin-fixed paraffin-embedded tissues. In addition, preliminary results suggest that OTLS microscopy is compatible with downstream archival H&E histology and immunohistochemistry (IHC) analyses, which are currently relied upon for definitive clinical diagnoses. These results facilitate the clinical translation of OTLS microscopy for intraoperative guidance of breast conserving surgery as well as other surgical oncology procedures.