Dual-scale and Dual-channel Oblique Plane Microscopy for Slide-free Histology

Abstract

Histological examination during cancer surgery is critical for resection margin determination. The current examination method based on frozen sectioning has several limitations including long processing time and sampling errors. Various optical methods have been developed to resolve these limitations by 3D imaging without sectioning. However, these optical methods do not satisfy the features of high-throughput, high-resolution, and simple configuration all together. In this study, dual-scale and dual-channel oblique plane microscopy (D2OPM) is developed for high-throughput and high-resolution histological examination without sectioning. D2OPM is a single-objective light sheet microscopy employing dual excitation wavelengths and a custom image splitter for simultaneous dual channel imaging. Dual-scale oblique plane imaging is implemented by using two objective lenses with different magnifications and adjusting the angle of illumination light sheet. Image throughput up to 1cm2 /~1.3min in meso-scale imaging and lateral and axial resolutions down to 0.6 and 1.2 μm in micro-scale imaging are achieved. Also, under-sampling and deep learning-based image restoration is applied to the micro-scale imaging for 10-time image throughput enhancement. D2OPM is tested on various human cancer specimens including the colon, stomach, and pancreas both qualitatively and quantitatively, with reference to standard histological images. As D2OPM provides cellular information comparable to slide histology in high-throughput, it may have the potential for intraoperative slide-free histology.