Digital Pathology, also referred to as Telepathology and Whole Slide Imaging (W.S.I.), is the process of producing high resolution digital images from tissue sections on glass slides, and subsequent evaluation. These glass slides are normally examined under a microscope by a pathologist as part of the diagnostic process. The emergence of digital pathology now means that digital images are stored on secure servers and can be viewed on computer monitors; enabling pathologists to work remotely and to collaborate with other colleagues and/or when second opinions are needed.
Conventional Histopathology
Histopathology is conventionally performed by certified pathologists using a light microscope. This histopathological examination is not an exercise in “picture matching” for it represents a careful step by step evaluation of tissue and cellular patterns. This includes assessment of size, shape, staining characteristics and topographical tissue and cell organizations and integration into meaningful biological conclusions, with considerations of the overall macroscopic and microscopic pathology as well as other related medical disciplines. Species specificity, anatomy, artefacts, control references and experience of the study pathologist are considered key factors in this process. Additional semi-quantitative techniques and artificial intelligence (A.I.) can also be valuable additional techniques for research purposes and decision support.
Digital Pathology: the future of diagnostics
We have been following the developments of Digital Pathology over the recent years, and it seemed good for peer review and/or educational purpose (e.g. Academic Hospitals, large CROs) of limited number of slides, and long-distance tele-communication. In the past, next to conventional light microscopy, also peer review was done faster in a conventional way by reviewing the glass slides. In addition, in the past there were sometimes problems with proper scanning of every slide which was time consuming.Nowadays, however, the quality of images generated by using Digital Pathology is as good as conventional review of slides for all organ systems using digital pathology. The UMCU Academic hospital in Utrecht, The Netherlands was one of the the first hospitals world-wide going fully digital in pathology with a future-proof complete digital archive (2015).During and after this time, scan speed, resolution and quality of scans from glass slides (W.S.I.) have been markedly improved. In recent years, substantial increased amount of W.S.I. validation literature is published on this subject. For both in clinical pathology (human) and pre-clinical veterinary pathology practices, things have improved significantly with demonstration of excellent diagnostic concordance between W.S.I. and conventional microscopy. Nowadays, the application of Digital Pathology, when well performed, can match equally with conventional light microscopy in toxicologic pathology for the safety evaluation in toxicology studies in the development of new vaccines, medicines and chemicals.
Digital Pathology at Global Pathology Support
As part of GPS continuing commitment to enable our clients to reach their development goals, we are now excited, next to conventional histopathology using the light microscope, to also deliver innovative GLP validated Digital Pathology; Full Histopathology Evaluations and Peer Review solutions from preclinical toxicology studies on a Global scale. This option (Digital Pathology) can now also be performed from scans of histology slides from a large number of whole slide image formats (e.g. Hamamatsu, 3DHistech, Olympus, Aperio/Leica, Ventana/Roche, Philips, Zeiss scanners etc. ).For more information: bob.thoolen@gpstoxpath. +31 (0)70 3142404
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