Caitlin Smith has a B.A. in biology from Reed College, a Ph.D. in neuroscience from Yale University, and completed postdoctoral work at the Vollum Institute.
Digital pathology systems enable the automated scanning, imaging and storage of histological slide data for analysis by pathologists.
Why does that matter? Traditional histological glass slides are vulnerable to breakage and tissue degradation, but the records they represent must be preserved. Digital image files provide reliable image quality and require far less space.
Digital pathology also speeds patient treatment by providing clinicians easier access to slide-based data. A slide can only be in one place in one time, and if multiple physicians need to examine the slide, the pass-around can delay treatment significantly. A digitized slide, on the other hand, can be read by anyone (with approved access), anywhere, at any time.
This is where digital pathology comes in. By scanning the slide to create a “digital slide,” many of these issues are solved at once.
Tools for pathologists
“Digital pathology ... [helps clinicians] make efficient and informed treatment decisions,” says Jeanelle Taverni, marketing manager for digital pathology at Ventana Medical Systems (of Roche Diagnostics). Ventana's image-analysis tools, for example, “allow consistent and objective interpretations that help reduce inter- and intra-observer variability in the interpretation of immunohistochemistry stains.”
Ventana’s Virtuoso image- and workflow-management software gives clinicians access to digitized slides from anywhere. Designed by pathologists, this web-based application also facilitates real-time collaboration for consultations and teaching.
Virtuoso can be paired with Ventana’s iScan Coreo scanner for image acquisition. The iScan Coreo is a brightfield slide scanner for up to 40x magnification, and it features the iScan Coreo Live Mode, a web-based application “which enables a pathologist to connect to the scanner from a remote location and review the slides within the system, without being in the same location as the glass slide,” says Taverni.
For research applications, Ventana offers its newest scanner system, the iScan HT, for high-throughput pathology workflows. The iScan HT “offers a 360-slide capacity at both 20x and 40x magnifications, with scan times of less than a minute at 20x for a 15 x 15 mm piece of tissue,” Ventana says.
Another software offering from NovoPath™ aims to smooth clinicians’ workflows by enabling easy access to the slides they need. The NovoPath Anatomic Pathology Information and Distribution System is an anatomic pathology laboratory information management software (LIMS) platform. It connects to slide scanners to import patient demographics, along with digital images, and manages tasks such as acquiring images, printing labels, signing off electronically, reporting and dictating. “Diagnostic data is easily captured and consolidated into a pathology report regardless of where the pathologist workstation exists relative to the imager or the pathology database, says Rick Callahan, vice president of sales and marketing at NovoPath. “ The digital image could be imported directly into the pathology report so that a comprehensive integrated pathology report could be sent out via the web to the appropriate clinicians.”
With increasing digitization of slides, some labs need faster scanners to keep up with demand. The Pannoramic 250 FLASH II slide scanner from 3DHISTECH “can scan 250 slides in a walk-away mode in just under eight hours on average at 40x resolution,” according to Ferenc Szipocs, sales engineer and account manager at 3DHISTECH. CaseCenter, the company’s software for slide management and teleconsultation, makes a newly scanned slide available to other locations around the globe in about 90 seconds. “When CaseCenter is connected to an HIS [hospital information system] or LIS [laboratory information system] system, the barcodes on the slides can drive an automatic process …, creating a case in CaseCenter, and Pannoramic scanners scan slides into this case. The case then can be assigned to the appropriate person for review,” Szipocs says. CaseCenter also can co-localize brightfield and fluorescence images, and an extended focus feature can merge the two focused images into one composite image.
ViewsIQ takes a different tack by enabling users to scan a specimen using their own microscope and optics. The company’s Panoptiq™ software lets users digitize samples at up to 100x magnification. “Based on sharpness calculations in the current field of view, our system automatically recognizes and retains the optimal focus attained by the user. This is especially important for thicker specimens and at higher magnifications, allowing the user to correct for unfocused regions before saving the digitized scan,” explains CEO Herman Lo. Panoptiq can construct a panoramic image of the specimen by attaching smaller views together like a mosaic. It also allows users to zero in on regions of interest (ROIs) for imaging at higher power and keeps track of where those ROIs are on the lower-power panoramic image. As with other software, ViewsIQ also facilitates remote access for telepathology consultations. Though the system isn’t as high-throughput as others, it is more affordable, Lo says, making it attractive to labs that need digital telepathology capabilities for fewer samples.
A complete package
In contrast to Panoptiq, other systems offer complete service packages for labs that routinely process high sample volumes and require high-throughput slide processing and analysis. The Philips Digital Pathology Solution, for instance, targets the complete high-throughput digital pathology workflow by speeding up slide digitization, acquiring images and providing imaging/telepathology tools to pathologists.
Hans Driessen, senior communications manager at Philips Digital Pathology, explains: “The solution is based on deep understanding of pathology workflow and processes combined with technology and IT capability from imaging and PACS,” or picture archiving and communication systems.
The solution reduces hands-on time so lab workers’ time is better spent. “We deliver a complete and turnkey solution designed for high-volume pathology labs, including scanner, image management system, storage, image algorithms, apps, service and maintenance and interfaces,” Driessen says. Two key components are the Philips Ultra Fast Scanner, which scans up to 60 slides per hour, and the company’s patented Continuous Auto-Focus technology.
Philips recently received clearance from the U.S. Food and Drug Administration to market a product that helps clinical pathologists determine the best treatment options for breast-cancer patients. The Her2/neu IHC Digital Manual Read enables pathologists to use Philips Digital Pathology Solutions to score HercepTest™ slides for the Her2 protein.
Data mining
Definiens takes scoring of digitized slides further by using image-analysis software to mine for information. Named Frost & Sullivan's 2013 Global Company of the Year for Tissue Diagnostics and Pathology Imaging Solutions, Definiens offers several software packages for digital pathology and data mining, including Tissue Studio®, Developer XD™ and Image Miner™. Definiens’ software uses Cognition Network Technology® to “automatically interpret the tissue phenome—the structures and their context in tissue—just like a human observer,” says Merrilyn Datta, Definiens’ chief marketing officer. “It can be incorporated in current pathology workflows to discover and develop biomarkers or therapies for oncology.”
Definiens’ digital pathology tools enable automatic scoring of the tissue phenome by counting biomarkers as well as morphological structures. “Combining the histological expertise of human observers with accuracy and consistency of computer-based methods turns pathology into a quantitative discipline,” says Datta.
Though digital pathology systems solve the problems of slide storage, slide degradation over time and slide sharing, the challenge of data storage and transfer looms. Imaging files can get big really fast, and the problem adds up as more slides are digitized. “As digital pathology becomes the global standard, pathology labs of all sizes will require an overall medical-imaging storage solution that is cost effective, flexible, secure and scalable,” says Taverni. In September 2013, Ventana entered into an agreement with EMC (a company specializing in data storage and IT infrastructure) to provide solutions to store and archive medical images, Taverni says.
Clearly the histopathology lab will never be the same. All the same, though, you may want to hold off on tossing your slides for now -- just in case.