Telepathology: The Future of Pathology
With the great urban and rural divide in healthcare, telepathology
can be a great asset to diagnostic healthcare
Dr Indumati Gopinathan
In today's digital world, telemedicine is an advancing science.
Connecting healthcare givers across distances, telepathology is one of the significant
applications of telemedicine. The telepathology services by the Armed Forces
Institute of Pathology in the US is one of the best models of telepathology
that many pathologists rely on. In the Indian economy, with the great urban
and rural divide in healthcare, telepathology can be a great asset to diagnostic
healthcare. In rural India that lack good pathology set-ups and in urban India
where pathology group practice is yet to catch up, telepathology can be a well
applied technological tool.
Telepathology is the electronic transmission of pathological images usually
derived from microscopes, from one place to another for interpretation and diagnosis.
Essentially, it involves a slide scanner, a large computer server and large
bandwidth network links. The images transmitted can be still images or a video
clip which again can be live or stored and forwarded transmissions. The images
transmitted could be selected by the person sending them or with the advanced
software, the recipient can have remote control of the microscopic stage, focusing
and objectives. In fact, it is possible to digitally scan the whole slide and
produce a virtual slide for actual viewing by a virtual microscope.
Teleradiology Vis-à-Vis Telepathology
Whilst teleradiology has taken off in a big way, in contrast, telepathology
is still not that widespread. Multiple factors are responsible for this situation.
- Though both deal with images and not live patients,
images produced in radiology are already digitised. There is no necessity
to convert the image into its digital form which means there is no need to
scan or photograph the image before it is electronically delivered. In contrast,
in pathology the original specimen is a slide. The image essentially has to
be digitised before transmission and this means a very real possibility of
loss of quality.
- Teleradiology has reached a stage where international
standards for image acquisitions, storage and transfer have already been set.
Such standards are lacking in telepathology.
- Radiology images are viewed at a comparatively limited
range of magnification whereas in histopathology, selected areas may be viewed
at a very wide range of magnification, like in a light microscope. To digitise
all the material on a slide at a resolution of x 1000 results in data files
of differing magnitude much larger than digital radiology images.
- When image standards and technical specifications
are lacking, system suppliers have no gold standard to follow and subsequently
there is no guarantee of image quality.
- Radiologists are trained to interpret images and
comprehend the underlying principles of digital imaging and factors influencing
their quality. In contrast, pathologists have never been trained to assess
digital imaging techniques for histopathology. Hence, they are less likely
to recognise and correct problems related to image quality competently.
Telepathology can help pathologists in India who commonly practice in smaller
labs dealing with routine histopathology or in smaller hospitals when they come
across unconventional cases. Without handing over blocks, a real-time consultation
with discussion can take place with telepathology, between two pathologists.
This is better than a conventional consultation as the local pathologist observes
and understands the diagnostic approach taken by the expert. Viewing images
cuts out on the money and travel time of a pathologist.
An Effective Tool
can have a crucial role in education and training in the following ways:
- Online cases and images are excellent tools of education,
supplementing standard books.
- Video clips from case conferences can be a part of
- The virtual slide technology can reduce the number
of microscopes in a class.
- Telepathology is an excellent tool to distribute
material from small biopsies that defy too many replicate sections. This helps
in external quality assurance. Participants can see and discuss the same images
and maintain a record for future reference.
However, the expertise for diagnosing through light microscopy and tele-images
need not be same. The role of image analysis and quantisation in telepathology
is vital. This is especially so in certain aspects of histopathology requiring
semi-quantification to asses tumour grade and dysplasia. These are subjective
and poorly reproducible. Various techniques of image analysis have been attempted,
but have not gained wide acceptance because of the resource implications of
producing the desired digital images and their accurate measurements. The question
of quality control and external quality assessment come into the fore as with
any new diagnostic procedure.
Problems in Telepathology
- If used for routine workload (telemicroscopy), the
problem arises if the centre lacks a pathologist who can use the facility
well or is ill trained to read digital images.
- Acceptance of responsibility by the local pathologist
for the final telepathology report that goes out is a point to be considered.
- Technical standards for image capture, storage and
transfer need to be well set.
- While viewing distant virtual slides, the factor
of time lag has to be considered which does not happen in a light microscope
- Image resolutions may be inadequate for assessing
nuclear chromatin pattern or glomerular pathology.
- If a lab solely relies on telepathology, there can
be damaging loss of local expertise.
- Training of new pathologists can become a problem
because they need to see and examine all kinds of actual specimen.
- Telepathology may prove difficult in cases of large
complex specimens that need to be grossed well and dissected in person.
- When volumes of referral practice increase, the distant
pathologist may find it difficult to schedule live teleconsultations without
- For technicians working with an on-site pathologist,
who helps solve problems on the spot, can be different from functioning with
a distant pathologist. It could dampen their morale.
The writer is a Consultant Pathologist and a domain specialist
and advisor for Space Telemedicine, a Chennai-based telemedicine company