Abstract
AIM: Over the past several decades, optical sectioning technologies have emerged as valuable tools for evaluating tissue histology. Unlike conventional tissue sectioning, these technologies allow for real-time intraoperative assessments and more efficient tissue triage. In the era of digital pathology, the demand for high-quality, high-throughput optical sectioning platforms is increasing, as they eliminate the need for traditional slide preparation and scanning, potentially transforming anatomical pathology workflows. While non-linear microscopy (NLM) has demonstrated promise in histological evaluation across various tissue types, its application in gastrointestinal tissue assessment remains unexplored. METHODS: This study extends the use of NLM to gastrointestinal histology and develops an image atlas to highlight its potential as an automated digital pathology platform. RESULTS: Our results indicate that NLM generates diagnostic-quality images comparable to traditional H&E slides. Moreover, NLM provides valuable three-dimensional (3D) spatial information, improving clinical evaluations of key histological features such as depth of invasion, lymphovascular and perineural invasion, tumour budding and margin assessment. Time-lapse videos further demonstrate NLM's capability to capture 3D histological structures up to a depth of approximately 100 µm. CONCLUSION: Our findings demonstrate that NLM can serve as an optical sectioning platform for gastrointestinal histology, providing both diagnostic-quality imaging and advanced 3D visualisation. The introduction of an NLM-based atlas has the potential to redefine anatomical pathology workflows and advance digital pathology image analysis.