Date Published: October 22, 2008
Publisher: Public Library of Science
Author(s): Ewert Linder, Mikael Lundin, Cecilia Thors, Marianne Lebbad, Jadwiga Winiecka-Krusnell, Heikki Helin, Byron Leiva, Jorma Isola, Johan Lundin, Juerg Utzinger
Abstract: BackgroundThe basis for correctly assessing the burden of parasitic infections and the effects of interventions relies on a somewhat shaky foundation as long as we do not know how reliable the reported laboratory findings are. Thus virtual microscopy, successfully introduced as a histopathology tool, has been adapted for medical parasitology.Methodology/Principal FindingsSpecimens containing parasites in tissues, stools, and blood have been digitized and made accessible as a “webmicroscope for parasitology” (WMP) on the Internet (http://www.webmicroscope.net/parasitology).These digitized specimens can be viewed (“navigated” both in the x-axis and the y-axis) at the desired magnification by an unrestricted number of individuals simultaneously. For virtual microscopy of specimens containing stool parasites, it was necessary to develop the technique further in order to enable navigation in the z plane (i.e., “focusing”). Specimens were therefore scanned and photographed in two or more focal planes. The resulting digitized specimens consist of stacks of laterally “stiched” individual images covering the entire area of the sample photographed at high magnification. The digitized image information (∼10 GB uncompressed data per specimen) is accessible at data transfer speeds from 2 to 10 Mb/s via a network of five image servers located in different parts of Europe. Image streaming and rapid data transfer to an ordinary personal computer makes web-based virtual microscopy similar to conventional microscopy.Conclusion/SignificanceThe potential of this novel technique in the field of medical parasitology to share identical parasitological specimens means that we can provide a “gold standard”, which can overcome several problems encountered in quality control of diagnostic parasitology. Thus, the WMP may have an impact on the reliability of data, which constitute the basis for our understanding of the vast problem of neglected tropical diseases. The WMP can be used also in the absence of a fast Internet communication. An ordinary PC, or even a laptop, may function as a local image server, e.g., in health centers in tropical endemic areas.
Partial Text: The Internet has made possible high standard educational undertakings with microscopy images also in the field of diagnostic medical parasitology (for an example, see: http://www.parasite-diagnosis.ch). However, the limitation until now has been that presentation of selected illustrations cannot replace working with a real microscope. The success of web-based virtual microscopy for histopatology  (www.webmicroscope.net) at the outset prompted us to demonstrate the histopathology of “the schistosome-infected mouse” which is presented in the beginning of this study. It soon became evident that some serious obstacles associated with education and quality control in medical parasitology can be solved using web-based microscopy, the main topic of this study.
Ten specimens on microscope slides were digitized. They are seen in Figure 1 as “thumbnails” corresponding to part of the established website for medical parasitology (www.webmicroscope.net/parasitology). In line with the current use of virtual microscopy for histopathology, we have digitized tissue samples obtained from a mouse experimentally infected with S. mansoni.
Introduction of virtual microscopy of entire parasitological specimens as a new tool brings “virtual microscopy” very close to working with a real microscope. The author has lost the privilege of selecting “typical” microscopy fields for publication. Artefacts and non-parasite material, which can be mistaken for helminth eggs and intestinal protozoan cysts, cannot be ignored in digitized whole specimens. By presenting digitized whole parasitological specimens of different types at our website, we have illustrated these points.