Telepathology is the practice of pathology at a distance. It uses telecommunications technology to facilitate the transfer of image-rich pathology data between distant locations for the purposes of diagnosis, education and research. Performance requires that a pathologist selects the video images for analysis and the rendering of diagnoses. The use of “television microscopy”, the forerunner of telepathology, did not require that a pathologist have physical or virtual “hands-on” involvement in the selection of microscopic fields-of-view for analysis and diagnosis.
An academic pathologist, Ronald S. Weinstein, M.D., coined the term in 1986. In a medical journal editorial, Weinstein outlined the actions that would be needed to create remote pathology diagnostic services. He and his collaborators published the first scientific paper on robotic telepathology. Weinstein was also granted the first U.S. patents for robotic telepathology systems and telepathology diagnostic networks. Dr. Weinstein is known to many as the “father of telepathology”. In Norway, Eide and Nordrum implemented the first sustainable clinical telepathology service in 1989; this is still in operation decades later.
It has been successfully used for many applications, including the rendering of histopathology tissue diagnoses at a distance. Although digital pathology imaging, including virtual microscopy, is the mode of choice for telepathology services in developed countries, analog telepathology imaging is still used for patient services in some developing countries.
Types of telepathology systems
Telepathology systems are divided into three major types: static image-based systems, real-time systems, and virtual slide systems.
Static image systems have the benefit of being the most reasonably priced and usable systems. They have the significant drawback in only being able to capture a selected subset of microscopic fields for off-site evaluation.
Real-time robotic microscopy systems and virtual slides allow a consultant pathologist the opportunity to evaluate histopathology slides in their entirety, from a distance. With real-time systems, the consultant actively operates a robotically controlled motorized microscope located at a distant site—changing focus, illumination, magnification, and field of view—at will. Either an analog video camera or a digital video camera can be used for robotic microscopy. Another form of real-time microscopy involves utilizing a high resolution video camera mounted on a path lab microscope to send live digital video of a slide to a large computer monitor at the pathologist’s remote location via encrypted store-and-forward software. An echo-cancelling microphone at each end of the video conference allows the pathologist to communicate with the person moving the slide under the microscope.
Virtual slide systems utilize automated digital slide scanners that create a digital image file of an entire glass slide (whole slide image). This file is stored on a computer server and can be navigated at a distance, over the Internet, using a browser. Digital imaging is required for virtual microscopy.