Efficient, gigapixel-scale, aberration-free whole slide scanner using angular ptychographic imaging with closed-form solution

TL;DR

This paper introduces a high-speed, large-field, aberration-free whole slide imaging system using angular ptychography with a closed-form solution, enabling detailed pathology imaging without z-scanning.

Contribution

The authors develop WSI-APIC, a novel gigapixel-scale imaging system that combines angular ptychography, efficient segmentation, and GPU-accelerated reconstruction for high-resolution, aberration-free pathology imaging.

Findings

Achieved 772 nm optical resolution with 10x/0.25 NA lens.

Captured 80-gigapixel phase images of standard slides.

Enhanced imaging efficiency by segmenting background regions.

Abstract

Whole slide imaging provides a wide field-of-view (FOV) across cross-sections of biopsy or surgery samples, significantly facilitating pathological analysis and clinical diagnosis. Such high-quality images that enable detailed visualization of cellular and tissue structures are essential for effective patient care and treatment planning. To obtain such high-quality images for pathology applications, there is a need for scanners with high spatial bandwidth products, free from aberrations, and without the requirement for z-scanning. Here we report a whole slide imaging system based on angular ptychographic imaging with a closed-form solution (WSI-APIC), which offers efficient, tens-of-gigapixels, large-FOV, aberration-free imaging. WSI-APIC utilizes oblique incoherent illumination for initial high-level segmentation, thereby bypassing unnecessary scanning of the background regions and enhancing image acquisition efficiency. A GPU-accelerated APIC algorithm analytically reconstructs phase images with effective digital aberration corrections and improved optical resolutions. Moreover, an auto-stitching technique based on scale-invariant feature transform ensures the seamless concatenation of whole slide phase images. In our experiment, WSI-APIC achieved an optical resolution of 772 nm using a 10x/0.25 NA objective lens and captures 80-gigapixel aberration-free phase images for a standard 76.2 mm x 25.4 mm microscopic slide.