TELEPATHOLOGY

Presenter : Dr.Janani Mathialagan 1st year Post-graduate Pathology

Overview: Definition 3 systems Dynamic Static Virtual Hybrid Advantages and disadvantages Telepathology in India Summary

What is Telepathology ?

Practice whereby pathologists render diagnoses from a distance by viewing electronically transmitted images rather than by examination of glass slides by themselves using a light microscope.

Images can be transmitted via

Ordinary telephone lines High speed digital lines Satellites Internet

Background

• Ronald S Weinstein coined the term – Telepathology in the year 1986

• Today- fourth-generation telepathology systems, so-called virtual

slide telepathology systems, being used for education applications

FATHER OF TELEPATHOLOGY

S.NO TELEPATHOLOGY TELERADIOLOGY1 Original specimen is usually

a glass slide; image must be digitised before transmission

Produces images that are already in digital form

2 Original quality of images may be lost as a result of digitisation of images

None of the original diagnostic information has been lost or degraded

3 Criteria still being established Well-established international standards in radiology for image acquisition, storage and transfer

4 No comparable requirement for training and assessment in digital imagingtechniques in histopathology

Radiologists trained to understand factors that influence digital image quality

5 Histopathology selected areas viewed at a very wide range of magnifications; larger number of data files

Images viewed at a relatively limited range of magnification;fewer data files

COMPONENTS OF A TELEPATHOLOGY SYSTEM

• A conventional microscope (Optional - motorised optics and stage)• A method of image capture• Telecommunication links between sending and receiving sites• Workstation at the receiving site with high quality monitor to view the

images • Mechanical Hardware to allow the receiving pathologist to control the

microscope from a distance and view the entire slide in ‘Real time’

Preimaging steps 1) Sample preparation

2) Staining by a histology laboratory;

Imaging steps 3) Formation of the digital image by a virtual slide scanner

4) Digital image sampling by the sensor (eg, camera)

Processing of 5) Image compression

digital information,

6)Transmission of the digital image file

7)Display of the digital image file on the

pathologist's video display

THREE SYSTEMS ARE CURRENTLY AVAILABLE: Dynamic Static Virtual

Static image systems Real time or Dynamic Hybrid

Involvescapturing of still images from a microscope and transmittingthem in an asynchronous mode (also known as the‘‘store-and-forward’’ method)..

With either a digital/ video camera with analog-to-digitaloutput,transfers a videostream from the remote site to the telepathology serviceprovider site in real-time

Combining both static and dynamicimage transmissions advantageous in telepathologypractice

Store and forward telepathology (static image based systems) Capturing images of the slide

Storing the image and forwarding to pathologist

Main use: 2nd opinions in difficult cases

AdvantagesDisadvantagesAccuracy approaches than of conventional poor image quality and field selection for large/complex specimens – handicaps of preselected images is more pronounced

LIMITATIONS OF STATIC IMAGE SYSTEM

• Only selected microscopic fields can be sent

• Selection of the field depends entirely on the acumen of the transmitting pathologist

• If the transmitting pathologist misses the field receiving pathologist

misses them too

WRONG DIAGNOSIS

DYNAMIC TELEPATHOLOGY

• Most appropriate system for frozen-section telepathology and for understaffed area.

• Involves the transmission of microscopic slide images to recipient in real time via live telecommunication.

• With the implementation of remote robotic microscope recipients can completely control the magnification and slide.

Dynamic Robotic telepathology

DISADVANTAGES:

1) Expensive and not easy to maintain.

Usually fitted with

a) charge coupled device (CCD) video camera

b) high-resolution video monitors,

c) proprietary software

d)high performance hardware (computer).

2) Needs a stable and broad-bandwidthtelecommunication link between the sender and the recipient

WHOLE SLIDE IMAGING• Also known as ‘Virtual microscopy’/ Wide field microscopy• Virtual slides - digitized slides where examination can be done in

different magnifications

• No need of having multiple images• Image acquisition of an entire microscopic slide done at all

magnifications available on the microscope.

• The software drives the motorized stage to acquire all fields of view in tiles and then seamlessly stitches the fields into a single image.

DISADVANTAGE:

• These virtual slides have extremely large file size, sometimes exceeding 1.5 GB

• Hence cannot be transferred easily with the present network bandwidth limitations.

• Therefore stored in 'virtual slide boxes' where database storage can be done on a central server.

• The fourth generation telepathology imaging systems use miniature microscope arrays (MMAs)

• The output from about 100 miniaturized microscopes is simultaneously captured by 100 individual digital images.

•  The result is a virtual slide that can be produced in minutes.

• Such systems promise to transform histopathological laboratories in the very near future.

Advantages:

• More interactive

• Easy to share

• Help generate teaching sets ( virtual slide boxes) that can include - wide case range - rare cases that do not fade, break or disappear

Comparison between the various modes of telepathology:

• Compared with the 68.8% to 95.0% accuracy involved with static images, previous studies have reported that the dynamic pathology method can achieve 86.0 to 96.4% diagnostic accuracy.

• Diagnostic accuracy is at least 3% to 5% higher with dynamic than static imaging.

• The Diagnostic accuracy from direct glass slide examination has been found to range between 94% and 97%.

Reasons why low-resolution dynamic telepathology has higher diagnostic accuracy than static telepathology:

(1) Dynamic telepathology transfers more image information to the pathologist who is performing the diagnosis

(2) Provides the pathologist with a better relation of different views from the microscope (virtual microscopy)

HYBRID TELEPATHOLOGY

Simultaneous transmission of both real-time microscopy and static images

• 2 major components located at the1) remote site and2) service provider site (receiving site)

• At the remote site- Dual viewing Light microscope

Digital photo camera and

Video camera

• Images from the digital camera are captured by the computer

projected on the screen

• A color video monitor connected with the digital processor, from which real-time images of the glass slides can be previewed

• Both are transmitted to the telelmedicine unit.

( equipped with Table microphones and an additional pair of CCD cameras for videoconferencing)

Hardware Equipment at Receiving Site

• Equipments with the same protocol capability needs to be installed on the computer.

• Personal computer with large display or two monitors is recommended.

• One monitor for real-time video and the other for still images.

• Real-time video and audio conferencing between the remote and receiving sites are available.

TELEMEDICINE UNIT

Use of telecommunication and information technology to provide clinical healthcare from a distance.

Eliminates distance barrier Improves access to medical services not available in

distant rural communities

Operation Specifications• Consultations initiated from either the remote site or the receiving site via

the telemedicine unit.

Telepathologist at the receiving site

Direct communication

Telepathologist at the remote site

• Orders from the telepathologist at the receiving site can be performed at the remote site.

Dual-viewing microscope

System setting at the remote site. Dual-viewing microscope is in the center.

Benefits of telepathology1) Expert opinion can be rapidly obtained

• Allows a pathologist rapidly to seek the opinion of a second pathologist

• No need for irreplaceable blocks or slides to leave the department

• A ‘live’ telepathology consultation allows pathologist and clinician to consider the case at the same time

2 ) Provision of an urgent (intra-operative) diagnostic service in the absence of a local pathologist

• The distant pathologist is usually provided with - remote control of a local microscope

- live streaming of image (a variant of dynamic method) – 2nd pathologist who is handling the slide in person is instructed by the pathologist in the receiving end. • More recently, development of virtual slide technology - an

alternative way to deliver the same type of service.

3) Image analysis

• Many aspects of routine pathology require semi-quantitative assessments such as tumour grade, degree of dysplasia, severity of inflammation or fibrosis.

• These assessments are subjective and poorly reproducible

• Attempts are made to improve these assessments by applying various techniques of image analysis to digital images.

4) Education and training

• Virtual slide technology - potential to allow many pathologists to view rare and educational cases

• Viewing images and cases online significantly reduces the time and cost of travelling

• Valuable in the undergraduate curriculum,

Challenges:1) Quality issues

There is no defined criteria in telepathology Such standards might include: - image resolution - colour depth that should be captured - speed with which images should be transferred - necessary qualities of any viewing station to ensure that the

captured is not degraded

2) Legal issues• Several legal issues that arise when a telepathology service is

used from outside national boundaries.

For example in European union –• The registration of the reporting pathologist must be recognised

by the regulatory body of the EU member state -An essential requirement in order to maintain proper standards of reporting.

3) Patient confidentiality

• Expert advice on data protection is needed if patient - identifiable or potentially identifiable information is being transmitted

4) Training in telepathology skills

• Skill at diagnosis using a microscope does not immediately

and automatically translate into skill at using a telepathology system

• Investment in training needed

• As telepathology systems become more widespread, assessment and revalidation procedures will increasingly have to incorporate the evaluation of knowledge and skills specific to telepathology.

5) Deskilling• Telepathology - great potential as a tool for training and education, • However, a particular category of specimen is routinely

allocated to reporting by a distant pathologist

Long-term result

loss of relevant local expertise.

• Particularly important problem in relation to the training of new pathologists, who must see all relevant specimen types.

6) Discrepancy reporting and audit

• When a telepathology system is being introduced, essential that a representative proportion of cases are ‘double reported’ by conventional and telepathology system to ensure diagnostic accuracy.

• The proportion of cases subjected to such double reporting may be reduced as experience is gained

7) Back up plan

• Laboratories must have procedures to maintain activity in the event of equipment failure.

• There must be procedures in place to ensure sufficiently rapid repair or replacement of sophisticated equipment

• The laboratory must remain prepared to revert to ‘conventional’diagnostic methods.

Telepathology in INDIA

Not lagging far behind.

The first exposure was provided at a symposium organized in the 50th Annual Conference of the Indian Association of Pathologists and Microbiologists in Mumbai in 2001 - named Telepathology: Today and Tomorrow.

Telepathology is yet to permeate into everyday activities for pathologists in India

1) Lack of agreement on a preferred technology

2) Lack of standardised criteria acceptable to the pathology community

3) One major drawback in rural India -sub-optimal preparation of slides.

4) Absence of a rapport between the sending pathologist and the consultant pathologist.

5) Resistance from senior histopathologists in India for the promotion of telepathology.

Summary• The methods of telepathology have potential to improve several aspects of pathology

practice, for the benefit of patient care.

• Need to agree accreditation standards for the use of telepathology, in

relation to its mode of use, image quality, training and communications

• Proficiency at diagnosis using a conventional microscope does not necessarily indicate proficiency at diagnosis using telepathology.

• Pathologists should ensure that they have verified that they have the abilities and equipment required to make accurate diagnoses either by convention or digital microscopy. (Double reporting)

REFERENCES

1)Telepathology: Guidance from The Royal College of Pathologists, October 2013 .Author- Professor James Lowe, Chair of the Specialty Advisory Committee on Cellular Pathology

2)Washington manula of surgical pathology 2nd edition

3) Asaranti Kar, Tushar Kar, Priyadarshini Biswal, Kaumudee Pattanaik, Pallavi Bhuyan, Rajashree Mallick, B. N. Mohanty . Use of Telemedicine in Postgraduate Pathology Education . International Journal of Clinical Medicine, 2013;7 : 304-08

Thank you