Tips for Slide Preservation

Vol. 19 • Issue 5 • Page 20
Perspectives in Pathology

Digital pathology systems are providing remarkable flexibility to pathologists by facilitating access to digital slide images, independent of glass slides or microscopes. Digital slides can be viewed, shared and analyzed in ways physical slides cannot-for consultation, pharmaceutical research and education.

Yet another valuable benefit of digital pathology is its use in the permanent archival and preservation of glass slide specimens and collections. Since many biological specimens prepared on glass slides may degrade, break or get lost, there is a tremendous advantage to creating a permanent digital slide archive and database of precious and rare slide specimens and collections for posterity.

Beyond Storage

The value of archival for cytology slides is especially high for risk management purposes because cytology slides are one-of-a-kind and re-cuts are not possible. If a physician sends a cytology slide out for consultation, the risk factor is very high because the glass slide cannot be reproduced. Digitizing cytology slides for permanent archival ensures that a record is available for later retrieval.

The availability of high-resolution digital slide databases also assists in resident training by providing Internet access to non-negative cases generated at remote hospital sites. Residents can gain increased exposure to variations in disease processes via a searchable, de-identified database of case information obtained through inpatient, outpatient and consultation services. They can view frozen sections even if they were not present during the procedure, make interpretations and compare them to those made at the time of the frozen section sign-outs.

One of the most valuable benefits of digital slide archives is for decision support. Unlike text references, details in a digital slide can be viewed in context to provide pathologists and students with comprehensive pathology content to facilitate self learning or decrease the time required by pathologists to research complex pathology cases. Annotated digital slide databases are easy to create and can be organized to facilitate the retrieval of digital slides based on specific criteria.

Over the course of their careers, many pathologists assimilate collections of glass slides that may be used as reference material for decision support. Digital pathology makes it possible to create replicable, non-decaying copies of entire glass slides for a repository of personal digital slides or collections that can be shared with colleagues across the globe without risking the loss of original specimens.

Digital slide archives are the equivalent of viewing glass slides on a microscope and are optimally focused, captured at standard microscope magnification (typically 20x and 40x), and free from artifacts or optical aberrations. Some digital pathology systems provide free viewing software, which is fast and easy to use and freely downloadable so that digital slide archives can be accessed and shared with no added cost.

Preserving Collections

Dr. Juan Rosai, a world-renowned expert and consultant in surgical pathology, has maintained an extensive glass slide seminar series collection inherited from the late Lauren V. Ackerman, MD, a leader in the discipline of surgical pathology. The collection consists of almost 20,000 cases originally presented at more than 1,400 pathology seminars and comprises digital images of the original slides, clinical history and diagnostic summaries.

Efforts are under way between the United States and Canadian Academy of Pathologists (USCAP) and a leading digital pathology vendor to digitize, archive and make the historical Dr. Juan Rosai Collection of Surgical Pathology Seminars available online at no cost to the public via a Web-based digital slide sharing service. Pathologists around the world will be able to access the collection to learn about the evolution of surgical pathology and examine the material utilized by experts for case evaluation over the past 60 years. The project will include the creation of a custom-built website that will dynamically interface with the digital slide collection to provide diagnostic and historical context and interactive learning tools.

In a similar project, New York University College of Dentistry (NYUCD) was the recipient of a vast glass slide collection of bone tissues created by Dr. Donald H. Enlow, author of numerous papers and books on the growth and organization of bone. The collection included human and animal specimens from various projects.

Comprising nearly 100,000 sections, the collection held valuable potential for researchers within numerous fields, including paleontology, hard tissue biology, orthodontics and anthropology. Over time, some of the specimens began to deteriorate, and curators wondered how they could preserve the contents of the rare slides and also make them broadly accessible to interested parties without fear of damage or loss. NYUCD recognized the value of digital pathology and created the Donald H. Enlow digital image library.

Digital pathology is a proven technology for the archival of glass slides and collections to support permanent preservation and decision support and advance scientific knowledge.

Chrystal Adams is a product manager at Aperio.