What Is Whole Slide Imaging?

Whole slide imaging (WSI) is the process of scanning an entire glass microscope slide to create a high-resolution digital image that can be viewed on a computer or through a web-based viewer. Instead of examining tissue only through a traditional microscope, researchers can zoom in, zoom out, pan across the full section, and review histology details digitally. Whole slide imaging is also commonly referred to as whole slide scanning, because the physical slide is digitized into a navigable whole slide image.

In research settings, whole slide imaging helps teams review tissue morphology more efficiently, share slides remotely, support collaborative interpretation, and build digital archives for future analysis. It is widely used for H&E slides, IHC, special stains, immunofluorescence panels, and tissue microarrays in biotech, pharma, CRO, and academic workflows.

Figure 1. Example of a whole slide image displayed in an interactive viewer, allowing users to zoom, pan, and review tissue sections digitally.

How Does Whole Slide Scanning Work?

Whole slide scanning begins by placing a prepared glass slide into a digital slide scanner. The system captures the entire tissue section at high resolution, typically at 20x or 40x magnification, and stitches the scanned fields into a single navigable whole slide image. This digital file can then be opened in viewer software or a secure web-based platform for remote review, annotation, sharing, and downstream analysis.

Depending on the application, whole slide scanning may be performed on brightfield slides such as H&E, IHC, and special stains, or on fluorescence slides including IF and multiplex IF panels. File outputs may include formats such as SVS, TIFF, or MRXS, depending on the scanner and workflow requirements. Once digitized, slides can be archived, shared with collaborators, or used for image analysis and AI-ready research workflows.

Figure 2. Whole slide scanning converts a glass microscope slide into a digital whole slide image that can be viewed, shared, and analyzed electronically.

Whole Slide Imaging vs Traditional Microscopy

Traditional microscopy requires a user to examine a glass slide directly through the eyepiece of a microscope, usually one field of view at a time. In contrast, whole slide imaging converts the entire tissue section into a digital file that can be reviewed on screen, navigated at different magnifications, and shared with other users remotely.

This digital approach makes slide review more flexible and collaborative. Instead of needing physical access to the microscope and slide, researchers can open whole slide images from different locations, annotate regions of interest, compare samples side by side, and build searchable digital archives. While traditional microscopy remains important in many laboratory settings, whole slide imaging offers major advantages for remote review, data sharing, and image analysis in research workflows.

Figure 3. Traditional microscopy relies on direct viewing through a microscope, while whole slide imaging enables digital review, sharing, and analysis of the entire slide.

Benefits of Whole Slide Imaging for Research

Whole slide imaging offers several important advantages for research teams working with histology data. Because slides are digitized into high-resolution files, they can be reviewed remotely, shared across locations, and archived for future access without relying on physical slide handling. This is especially useful for biotech companies, CROs, and academic laboratories that need efficient collaboration across multiple users or sites.

Whole slide imaging also supports more consistent review workflows. Researchers can zoom in on regions of interest, compare slides side by side, annotate findings, and revisit the same digital section whenever needed. In addition, digital slides can be integrated into image analysis pipelines, AI model development, and data-driven pathology research, making whole slide imaging valuable not only for visualization but also for scalable downstream analysis.

Common Applications of Whole Slide Imaging

Whole slide imaging is used across a wide range of histology and pathology research applications. In routine tissue evaluation, it is commonly applied to H&E slides, IHC slides, and special stains that need to be reviewed, shared, or archived digitally. Whole slide imaging is also widely used for fluorescence imaging workflows, including IF and multiplex IF panels, where researchers need high-resolution visualization and remote access to scanned slides.

Beyond routine slide review, whole slide imaging is valuable for tissue microarrays (TMAs), biobank digitization, longitudinal study archiving, and AI-ready dataset generation. By converting physical slides into digital files, research teams can build searchable slide collections, support distributed collaboration, and integrate histology images into computational analysis workflows more efficiently.

Figure 4. Human breast tissue microarray (TMA) stained for HER2-CY5 and displayed as a whole slide image. Click the image to view the full whole slide scan.

Whole Slide Imaging vs Whole Slide Scanning: Is There a Difference?

In most research and digital pathology contexts, the terms whole slide imaging and whole slide scanning are closely related and are often used interchangeably. Whole slide imaging usually refers to the overall digital result and workflow, including the creation, viewing, sharing, and analysis of a digital whole slide image. Whole slide scanning more specifically describes the step of digitizing the physical glass slide using a scanner.

In practice, both terms point to the same core concept: converting a glass microscope slide into a high-resolution digital image that can be reviewed electronically. For this reason, researchers may search for either whole slide imaging or whole slide scanning when looking for information, scanners, workflows, or service providers.

How to Choose a Whole Slide Imaging Service

When choosing a whole slide imaging service, it is important to consider image quality, scanner capability, turnaround time, file format compatibility, and viewing options. Research teams may also want to evaluate whether the provider supports brightfield and fluorescence slides, secure cloud access, large-format slides, tissue microarrays, and downstream image analysis workflows.

A strong whole slide imaging service should make it easy to digitize slides, access images remotely, and integrate digital files into collaborative or data-driven research workflows. For biotech, pharma, CRO, and academic teams, the right provider can improve efficiency, reduce slide handling, and support more scalable pathology and histology review.

Need help with slide digitization for your research? Learn more about our whole slide imaging service.

Frequently Asked Questions About Whole Slide Imaging

Q: What is whole slide imaging?

A: Whole slide imaging is the process of scanning an entire glass microscope slide to create a high-resolution digital image that can be viewed, shared, and analyzed on a computer or through a web-based viewer.

Q: Is whole slide imaging the same as whole slide scanning?

A: These terms are closely related and are often used interchangeably. Whole slide scanning usually refers to the act of digitizing the slide, while whole slide imaging can also include viewing, sharing, and analysis of the digital image.

Q: What are the benefits of whole slide imaging for research?

A: Whole slide imaging helps research teams review slides remotely, share images easily, build digital archives, support collaboration, and integrate histology data into image analysis and AI workflows.

Q: What types of slides can be used for whole slide imaging?

A: Whole slide imaging can be used for brightfield slides such as H&E, IHC, and special stains, as well as fluorescence slides including IF and multiplex IF panels. It is also commonly used for tissue microarrays and archived research slides.

Q: What file formats are used in whole slide imaging?

A: Common whole slide imaging file formats include SVS, TIFF, MRXS, and other scanner-compatible digital slide formats, depending on the workflow and imaging platform.

Q: Why is whole slide imaging important in digital pathology?

A: Whole slide imaging is a core part of digital pathology because it converts physical slides into digital files that can be reviewed, shared, annotated, archived, and analyzed electronically.