# Digital pathology and whole-slide images (WSI)

Source: https://onco.cc/terms/digital-pathology-wsi/  
OnCo record `digital-pathology-wsi` (Term). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

Digital pathology scans glass slides into gigapixel images that can be viewed, shared and analysed by software, which is what makes AI on pathology possible.

## Summary

Digital pathology manages and analyses information from digitised specimen slides, using virtual microscopy to view, share and analyse slides on screens, with applications in diagnosis and AI (Wikipedia). A whole-slide image is typically 100,000 pixels across at 40x, stored as a pyramid in vendor formats such as Aperio .svs; OpenSlide reads them vendor-neutrally. Slides are far too large for a neural network at once, so they are cut into tiles, encoded and pooled.

## Fields

- Kind: Term
- Last checked: 2026-09-24
- Also known as: digital pathology; whole-slide image; whole-slide images; whole slide image; WSI; gigapixel slide; gigapixel slides; .svs file; slide scanner image
- Tags: cansim-terms

## Notes

- Listed in the CanSim terms map 1.0.0 (docs/onco/terms.json, generated 2026-09-24), CC BY 4.0, attribution: CanSim project, an open, public-data-first cancer foundation-model programme; CanSim page path /terms/wsi-histopathology.

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Digital_pathology
- Goode et al., OpenSlide: a vendor-neutral software foundation for digital pathology (J Pathol Inform 2013): https://doi.org/10.4103/2153-3539.119005
- Wikipedia: https://en.wikipedia.org/wiki/Digital_pathology

## Connected records

- terms: [Array and table formats: HDF5, Zarr, OME-Zarr, Parquet](https://onco.cc/terms/hdf5-zarr-parquet/), [Cancer AI vocabulary (CanSim terms map)](https://onco.cc/terms/cancer-ai-vocabulary/), [Clinical text: EHR notes and pathology reports](https://onco.cc/terms/ehr-text-pathology-reports/), [H&E staining (haematoxylin and eosin)](https://onco.cc/terms/h-and-e-staining/), [Magnification (20x, 40x) and microns per pixel](https://onco.cc/terms/magnification/), [Tile and patch encoding of slides](https://onco.cc/terms/tile-patch-encoding/)
- technologies: [Digital pathology & AI](https://onco.cc/technologies/digital-pathology-ai/), [Whole-slide scanners and image management](https://onco.cc/technologies/whole-slide-scanners/)

---
JSON: https://onco.cc/api/v1/entities/digital-pathology-wsi.json