Light Sheet Theta Microscopy for High-resolution Quantitative Imaging of Large Biological Systems

Recent advances in tissue clearing methods are enabling unprecedented optical access to large intact biological systems. These advances fuel the need for high-speed microscopy approaches to image large transparent samples quantitatively and at high resolution. While Light Sheet Microscopy (LSM), with its high planar imaging speed and low photo-bleaching, can be effective, scaling up to larger imaging volumes has been hindered by the use of orthogonal light-sheet illumination. To address this fundamental limitation, we have developed an approach − Light Sheet Theta Microscopy (LSTM) − that uniformly illuminates samples from the same side as the detection objective, eliminating limits on lateral dimensions without sacrificing imaging depth and speed. We present detailed characterization of LSTM, and show that this approach achieves rapid high-resolution imaging of large intact samples with superior uniform image quality than LSM. LSTM is a significant step in high-resolution quantitative mapping of structure and function of large intact biological systems.