Ali Lotfizadeh
Jan 25, 2012
Featured

Telepathology to aid diagnosis in the developing world

We often marvel at the newest and most cutting edge technologies in medical care and their impact on restoring health and prolonging life. Just last week, I wrote on the advances of tissue engineering and regenerative medicine after an American man received a synthetic trachea following removal of his cancerous trachea. However, in much of the developing world where the greatest burden of illness exists, access to even basic medical services is limited. The voids in access to medical care are even more pronounced when it comes to subspecialty care, including diagnostic subspecialties such as pathology and radiology. Specialized diagnosticians like pathologists are integral to effective healthcare delivery, as their expertise is in handling and preparing various human specimens, examining these specimens, and making diagnoses which dictate the course of medical care.


To help put the shortages in the developing world into perspective, lets consider the status of pathologists in three countries in Sub-Saharan Africa (SSA). Tanzania and Nigeria have approximately one clinical pathologist available per 3 million people. In Zambia, the entire country has only one surgical pathologist for a population of 12 million. These ratios contrast starkly with developed nations, where there are teams of subspecialized pathologists available to serve the population in much greater numbers. In SSA, maldistribution further compounds the problem: the majority of specialists live in urban areas, making access more limited in rural communities.

In recent years, the use of wireless and web-based technology has advanced the field of pathology in developing countries. This month, a report by Dr. Aliyah Sohani of Harvard University, published in the journal Analytical Cellular Pathology, describes a pilot project using static digital telepathology (SDT) for diagnostic purposes. The department of pathology at Harvard University School of Medicine and Massachusetts General Hospital donated four multi-head microscopes with digital cameras to several hospitals in East Africa. Because of a shortage of pathologists and lack of subspecialists, the team of healthcare providers in Africa took digital photos of specimens that were challenging to diagnose and put these images on an internet-based platform. Pathologists in the United States accessed these images, reviewed them, and consulted with subspecialists such as dermatopathologists (skin pathologists) or hematopathologists (pathologists specializing in blood disorders) to help diagnose the most challenging cases. In another study published this month in the Journal of Telemedicine and Telecare, Dr. Sohani’s team has shown that when telepathology is used in the diagnosis of challenging cases, there is strong consensus between different pathologists. Six independent pathologists reviewed images from forty specimens in East Africa and agreed on approximately 70 – 90% of cases. While it is imperative to build on these pilot projects and conduct studies with larger samples, these findings hold great promise, as they are a testament to the feasibility of successfully using web-based technology to enhance diagnostic care for patients in the developing world via SDT.

One of the limitations of SDT is that the consulting pathologist in the remote location does not have control over various parameters of the samples they are examining. In May of 2011, a multidisciplinary team from the University of Pennsylvania, University of Maryland, University of California, Los Angeles, and the National Health Laboratory in Gaborone, Botswana installed a Zeiss robotic microscope at the laboratory in Gaborone. This interesting robotic technology allows the consulting sub-specialist to control the microscope from a distance and set parameters such as the stage position, focus, and magnification in such a way to get the best images for diagnosis.

Scientists at the University of California, Berkeley have further built on the field of telepathology to allow remote, on-site processing of certain tissue specimens using portable technology to diagnose malaria and tuberculosis. Using mobile telephones with digital cameras, built-in microscopes, and a small slot where blood smear slides can be placed, health workers in the field can rapidly process blood specimens of patients and use a mobile phone data network to transmit the information to a data center for diagnosis of malaria. This work has also led to the development of the CellScope by Dr. Daniel Fletcher’s team at UC Berkeley, a portable device that offers more sophisticated technology and allows magnifications from 5X to 60X. Dr. Fletcher’s team is now working with collaborators at UCSF and in Uganda, to determine how the CellScope technology compares to standard technologies in the diagnosis of tuberculosis.

Despite the advances, there are still barriers to making telediagnosis widely feasible. These include tissue or specimen processing abilities on the field, as well as a high-speed Internet connection and staff who can maintain the web-based technology which allows data transfer. While much of the developing world still lacks some of these basic technologies, the expansion of Internet technology and rapid growth of mobile phone networks could help make these advances more accessible to many in underserved parts of the world.

 

References:

Sohani, AR et al.  Analytical Cellular Pathology, 2012 Jan 1; 35(1): 25-30.

Kumar N et al.  Journal of Telemedicine and Telecare, 2012; 18(1):7-12. 

Fischer MK et al. Journal of the American Academy of Dermatology.  2011 May; 64(5): 986-7.