Basic aspects of and recent developments in telepathology in Europe, with specific emphasis on quality assurance

Telepathology is the diagnostic work of a pathologist from a distance and includes all specific fields of diagnostic pathology, such as frozen section services, expert consultation, cytometric and histometric measurement, and continuous education. For about 15 years experience has been collected at several universities in the United States and Europe based upon analog telephone lines (9.2 kbaud), digitized lines (ISDN, 64 kbaud), broad band connections (1.5 Mbaud) and the World Wide Web (28 kbaud). Potential use can be expected in the application of telepresentation, remote slide preparation, remote central diagnostics and telediscussion. The transfer of still images is well developed; that of live images is used in only a few institutions for frozen section services. The image quality and spatial resolution as well as the transfer speed are sufficient for expert consultations, morphometric measurements, quality assurance and education. All applications focus on discontinuous work flow. Although the European Community focuses on user needs and standardization aspects of telepathology by sponsoring a widespread telepathology project (Europath), implementation of telepathology into routine application in the continuous work flow has still to be developed. The technical equipment has still to be adjusted to the labor flow charts in routine pathologic diagnostic procedures. Telepathology seems to be the appropriate technique to offer both improvement in diagnostic quality and inclusion of the "control institution" into diagnostic responsibility.     

Technical aspects of telepathology with emphasis on future development.

Pathology undergoes presently changes due to new developments in diagnostic opportunities and cost saving efforts in health care. Out of the wide field of telepathology the paper selects three prototype applications: telepathology in teleeducation, expert advice for preselected details of a slide and finally telepathology for remote diagnosis. The most challenging field for remote diagnosis is the application in the frozen section scenario. The paper starts with the mental experiment to map conventional procedures to counterparts in telepathology. Technical opportunities and economical restrictions of telepathology equipment are discussed with respect to the components: electronic camera, display devices, haptic sensors and displays, available telecommunication channels and telepathology software. As an example and for illustration of the state of the art for an advanced telemicroscopy system able to perform remote frozen section diagnosis, the HISTKOM equipment is presented in more details. The section concerning future developments regards the aspects of the acceptance by tentative users, legal aspects, costs and affordability of equipment, the market for equipment components and the adequate telecommunication services. Further is regarded the mutual influence of properties of existing systems and application experiences gained with them on the next generation of equipment and application software. Conclusions and references close the paper.     

Diagnostic errors in interactive telepathology.

Telepathology (TP) as a service in pathology at a distance is now widely used. It is integrated in the daily workflow of numerous pathologists. Meanwhile, in Germany 15 departments of pathology are using the telepathology technique for frozen section service; however, a common recognised quality standard in diagnostic accuracy is still missing. In a first step, the working group Aurich uses a TP system for frozen section service in order to analyse the frequency and sources of errors in TP frozen section diagnoses for evaluating the quality of frozen section slides, the important components of image quality and their influences an diagnostic accuracy. The authors point to the necessity of an optimal training program for all participants in this service in order to reduce the risk of diagnostic errors. In addition, there is need for optimal cooperation of all partners involved in TP service.     

A nationwide telepathology consultation and quality control program in China: implementation and result analysis

Background

Telepathology may play an important role in pathology consultation and quality control for cancer diagnosis in China, as the country has the largest population of cancer patients worldwide. In 2011, the Pathology Quality Control Center of China and Ministry of Health developed and implemented a nationwide telepathology consultation and quality control program for cancer diagnosis in China. We here report the results of the two-year implementation and experiences.

Methods

the program built an Internet based telepathology platform to connect participating hospitals and expert consultants. The hardware and software used for the platform were validated in previous validation studies in China. The program had three regional centers consisting of Peking Union Medical College, Huasi Medical College of Sichuan and 2nd affiliated hospital of Zhejiang University. It also had 20 provincial consultation centers based in the provincial referral hospitals. 80 provincial or national pathologists served as expert consultants for the program, providing telepathology consultation for cancer diagnosis for more than 60 participating hospitals.

Results

from 2011 to July 2013, 16,247 pathology cases were submitted to the platform for consultation. Among them, 84% were due to diagnostic difficulty and 16% were due to request by patients. The preliminary diagnosis provided by submitting pathologists were in agreement with expert opinion in 59.8% of cases but was in disagreement with expert opinion in 24.2% of cases. 16.0% of cases were not provided with preliminary diagnosis. The distribution of pathology cases by system or organ were: digestive system, 17.3%; gynecologic system, 16.7%; head and neck, 15.7%; bone and soft tissue, 10.4%; lung and mediastinum, 8.6%; breast, 7.6%; urinary system, 7.5%; hematopathology, 6.4%; skin, 5.2%; neuropathology, 2.5% and cytopathology, 1.3%. Expert consultants also provided assessment of quality of slide preparation and staining, online lectures and guidance for pathology quality control.

Conclusion

our results of two years' implementation indicated that telepathology could solve the problem of uneven distribution of pathology resources and provide a solution for countrywide pathology quality control in China. Telepathology could play an important role in improving pathology diagnosis in China.

     

Use of virtual slide system for quick frozen intra-operative telepathology diagnosis in Kyoto,Japan

We started to use virtual slide (VS) and virtual microscopy (VM) systems for quick frozen intra-operative telepathology diagnosis in Kyoto, Japan. In the system we used a digital slide scanner, VASSALO by CLARO Inc., and a broadband optic fibre provided by NTT West Japan Inc. with the best effort capacity of 100 Mbps. The client is the pathology laboratory of Yamashiro Public Hospital, one of the local centre hospitals located in the south of Kyoto Prefecture, where a full-time pathologist is not present. The client is connected by VPN to the telepathology centre of our institute located in central Kyoto. As a result of the recent 15 test cases of VS telepathology diagnosis, including cases judging negative or positive surgical margins, we could estimate the usefulness of VS in intra-operative remote diagnosis. The time required for the frozen section VS file making was found to be around 10 min when we use x10 objective and if the maximal dimension of the frozen sample is less than 20 mm. Good correct focus of VS images was attained in all cases and all the fields of each tissue specimen. Up to now the capacity of best effort B-band appears to be sufficient to attain diagnosis on time in intra-operation. Telepathology diagnosis was achieved within 5 minutes in most cases using VS viewer provided by CLARO Inc. The VS telepathology system was found to be superior to the conventional still image telepathology system using a robotic microscope since in the former we can observe much greater image information than in the latter in a certain limited time of intra-operation and in the much more efficient ways. In the near future VS telepathology will replace conventional still image telepathology with a robotic microscope even in quick frozen intra-operative diagnosis.     

How could static telepathology improve diagnosis in neuropathology?

The present paper reports our experience with, and our opinion of static telepathology as applied to neuropathology by means of the PHAROS acquisition system and conventional telephone data transmission (modem). The classical procedure of expert consultation based on surface mailing of histological slides is routinely performed, especially in highly specialized fields of pathology. Telepathology is an easy means of sharing scientific expertise at international level and could thus improve diagnosis particularly in neuropathology, where certain tumor types are very rare and complex to diagnose. Dynamic telepathology allows the referring pathologist to capture by himself images supporting their diagnosis. Using static telepathology the pathologist could be limited in diagnosis by problems in fields selection. We devoted a whole year to collecting all the technical parameters characterizing the use of digitized neuropathological data files in order to investigate the feasibility of telepathology and the extent to which its use could improve diagnoses. Our results on a series of 38 histological brain examinations illustrate how we successfully established an international connection between two departments of pathology in Belgium and the USA. The referring pathologists gave diagnoses in 35 cases and deferred only 3. Despite a time-consuming procedure for the telepathology session of a few cases, this tool provides easy access to expert diagnosis and real-time discussion, both of which are of considerable interest and offer significant improvements in neuropathology.     

Expanding application of digital pathology in Japan - from education,telepathology to autodiagnosis

Background

Digital pathology, i.e., applications of digital information technologies to pathology practice, has been expanding in the recent decades and the mode of pathology diagnostic practice is changing with enhanced precision. In the present study the changing processes of digital pathology in Japan were investigated and trends to future were discussed.

Methods

The changing status of digital pathology was investigated through reviewing the records of annual meetings of the Japanese Research Society of Telepathology and Pathology Informatics (JRST-PI) and of the Japanese pathology related medical and informatics journals. The results of the Japanese questionnaire survey conducted in 2008-2009 on telepathology and virtual slide were also reviewed. In addition effectiveness of an experimental automatic pathology diagnostic aid system using computer artificial intelligence was investigated by checking its rate of correct diagnosis for given prostate carcinoma digital images.

Results

Telepathology played a central role in the development of digital pathology in Japan. Both macroscopic and microscopic pathology digital images were routinely generated and used for diagnostic purposes in major hospitals. Virtual slide (VS) digital images were used first for education then for conference, consultation and also gradually for routine diagnosis and telepathology. The experimental automatic diagnostic aid system achieved the rate of correct diagnosis around 95% for prostate carcinoma and its use for automatic mapping of cancerous areas in a given tissue image was successful.

Conclusions

Advance in the digital information technologies gave revolutionary impacts on pathology education, conference, consultation, diagnosis, telepathology and also on pathology diagnostic procedures in Japan. The future will be bright for pathologists by the advanced digital pathology but we should pay attention to make the technologies and their effects under our control.

     

Experience with a dynamic inexpensive video-conferencing system for frozen section telepathology.

AIM: To evaluate the feasibility of an inexpensive, generally applicable video-conferencing system for frozen section telepathology (TP). METHODS: A commercially widely available PC-based dynamic video-conferencing system (Picture-Tel LIVE, model PCS 100) has been evaluated, using two, four and six ISDN channels (128-384 kilobits per second (kbs)) bandwidths. 129 frozen sections have been analyzed which were classified by TP as benign, uncertain (the remark probably benign, or probably malignant was allowed), malignant, or not acceptable image quality. The TP results were compared with the original frozen section diagnosis and final paraffin diagnosis. RESULTS: Only 384 kbs (3 ISDN-2 lines) resulted in acceptable speed and quality of microscope images, and synchronous image/speech transfer. In one of the frozen section cases (0.7%), TP image quality was classified as not acceptable, leaving 128 frozen sections for the analysis. Five of these cases were uncertain by TP, and also deferred by frozen section procedure (FS). One more benign and three malignant FS cases were classified as uncertain by TP. Three additional cases were uncertain by FS, but benign according to TP (in agreement with the final diagnosis). In one case, FS diagnosis was uncertain but TP was malignant (in agreement with the final diagnosis). Thus, test efficiency (i.e., cases with complete agreement) was 120/128 (93.8%, Kappa = 0.88) between FS and TP. Sensitivity was 93.5%, specificity 98.6%, positive and negative predictive values were 97.7% and 96.0%. Between TP and final diagnosis agreement was even higher. More importantly, there was not a single discrepancy as to benign-malignant. Moreover, there was a clear learning effect: 5 of the 8 FS/TP discrepancies occurred in the first 42 cases (5/42 = 11.9%), the remaining 3 in the following 86 cases (3/86 = 3.5%). DISCUSSION: The results are encouraging. However, TP evaluation is time-consuming (5-15 min for one case instead of 2-4 min although speed went up with more experience) and is more tiring. The system has the following technical drawbacks: no possibility to point at objects or areas of interest in the life image at the other end, resolution (rarely) may become suboptimal (blocky), storage of images evaluated (which is essential for legal reasons) is not easy and no direct control of a remote motorized microscope. Yet, all users were positive about the system both for telepathology and personal contact by video-conferencing. CONCLUSION: With a relatively simple videoconferencing system, accurate dynamic telepathology frozen section diagnosis can be obtained without false positive or negative results, although a limited number of uncertain cases will have to be accepted.     

Virtual telepathology in Egypt,applications of WSI in Cairo University

Telepathology, the practice of pathology at a long distance, has advanced continuously since 1986. Today, fourth-generation telepathology systems, so-called virtual slide telepathology systems, are being used for education applications. Both conventional and innovative surgical pathology diagnostic services are being designed and implemented as well. We have a successful experience in Egypt in applying the static & dynamic techniques in a pilot project between the Italian Hospital in Cairo (NPO) and the Civico Hospital in Palermo This project began in 2003 and continued till now. In 2004, centers in Venice, London and Pittsburgh participated actively in our project. During the past seven years we consulted on many problematic pathological cases with these different specialized pathological centers in Italy, UK & USA. In addition to the highly specialized scientific value of consulting on the cases and exchanging knowledge, we saved a lot of time and money and succeeded in providing our patients with a better medical service. In view of this success we have already established a new Digital Telepathology unit (DTU) in the pathology department, Cairo University, using the latest technique of telepathology which is Whole Slide Imaging (WSI) since one year. This unit is considered the first Digital pathology unit in all the universities of the whole Middle East. During the passed year we created a digital pathology library for the under graduate students using the WSI technique and changed the teaching method of the histopathology slides to be completely digital. We are building another digital pathology library (for post graduate candidates) which will be available to all pathology candidates in Egyptian universities & universities in the surrounding Arabic countries. We are also creating a digital pathology network between pathology centers in the Middle East for exchanging knowledge & telepathology.     

Reliability of telepathology for frozen section service.

One of the most promising applications of telepathology (pathology at a distance by electronic transmission of images in pathology) is frozen section diagnosis, especially because by means of this tool operations requiring an intraoperative histopathological diagnosis are feasible at hospitals without a pathologist on-site. For the introduction of this diagnostic tool into pathologist's daily practice the evidence of its diagnostic accuracy comparable to that of the conventional frozen section diagnosis is crucial. For this purpose the literature on the diagnostic accuracy of telepathological frozen section diagnosis was reviewed. In a metaanalysis these studies and reports, in which a total of more than 1290 cases had been examined, showed a slightly lower overall diagnostic accuracy (of the telepathological frozen section diagnosis) of about 0.91 than the conventional frozen section diagnosis with an average accuracy of about 0.98 found in an analysis of several studies (on frozen section diagnosis of different organs). This difference is at least predominantly caused by a higher rate of deferred and false negative frozen section diagnoses in the telepathological method, while the specificity of both methods, each more than 0.99 was not significantly different. In conclusion, the introduction of a telepathological frozen section diagnosis for hospitals without an acceptable access to a pathologist is justifiable already at the current state of the technological development especially when considering the advantages (time saving, reduction in costs) compared to the alternative of surgical interventions without access to an intraoperative diagnosis.     

Constructing a local district telepathology network in Japan. Diagnosis of intraoperative frozen sections via telepathology over an integrated service digital network and the National Television Standard Committee System

OBJECTIVE: To construct a local telepathology network between the Department of Pathology, Tohoku University Hospital, and Koritu Kesennuma Hospital, about 150 km away. STUDY DESIGN: Tohoku University Hospital is connected with Koritu Kesennuma Hospital by an integrated service digital network for telepathology using the National Television Standard Committee system. The cases submitted for telepathology were limited to those in which a rapid intraoperative diagnosis was made on frozen sections. RESULTS: At this writing, more than 200 cases were diagnosed during a period of 2.5 years. The cases submitted increased with time, amounting to 150 in 1996. In some cases the use of telepathology proved to be fairly advantageous. For example, in one case a radical operation was avoided because of a diagnosis on intraoperative frozen sections. DISCUSSION: There are problems to be solved before telepathology becomes available for practical use: (1) misdiagnosis due to poor quality of instruments, including the transmission cable and pictures; (2) cost-benefit ratio, (3) protection of patients' privacy, and (4) overwork for pathologists. The Japanese government will officially accept telepathology as a means of medical examination in the future. Despite some problems left, telepathology is a promising technology.     

Virtual slides: application in pulmonary pathology consultations

The Virtual Slide (VS) is an interactive microscope emulator that presents a complete digitized tissue section via the Internet. A successful implementation of VS has been observed for educational, research venues and quality control. VS acquisition for consultative pathology is not so common. The purpose of this study was to explore the efficacy and usability of VS in the consultative pulmonary telepathology. 20 lung tumors entered the study. The performance was programmed for 2 medical centers specialized in pulmonary pathology (beginner and advancer in telepathology). A high-quality VSs were prepared by Coolscope (Nikon, Eclipsnet VSL, Japan), and were evaluated via the Internet. The cases were reviewed for the second time with conventional light microscope. VS diagnostic accuracy and the interobserver variability were evaluated. Also the time taken by examiners to render the diagnoses and time needed to scan the microscopic slide were analyzed. Percentage concordance between original glass-slides diagnosis and diagnosis for VSs was very high. Pathologists found the download speed of VSs adequate; experience in telepathology reduced the time of VS diagnosis. VS implementation suggests advantages for teleconsulation and education but also indicate some technical limitations. This is the first Polish trial of VS implementation in telepathology consultative service.     

Comparison of different telepathology solutions for primary frozen section diagnostic.

In a retrospective study on a set of 125 cases we compared the following three telepathology solutions for primary frozen section diagnosis: ATM-TP (connection via ATM), TPS 1.0 (connection via LAN) and TELEMIC (connection via Internet), which represent different concepts of telepathological procedures. A set of 125 routine frozen sections (breast) was selected from the Charité cases of the year 1999. Four experienced pathologists diagnosed retrospectively all of these cases using the ATM-TP and TPS systems and 53 of them with the TELEMIC system. Using the ATM-TP we recorded no false positive (0%), 4 false negative (3.2%) and 4 deferred (3.2%) cases. Using the TPS we recorded no false positive (0%), 4 false negative (3.2%) and 4 deferred (3.2%) cases. Using the TELEMIC we recorded in 53 cases no false positive (0%), no false negative (0%) and 16 deferred (30.2%) cases. The average time of 2.2 minutes per case using ATM-TP is also short enough for routine frozen section diagnostic. This is also true for the TPS system with 7.2 minutes per case.     

The telepathology and teleradiology network in Croatia.

Telepathology as a demanding branch of telemedicine poses a real challenge to experts. The introduction of telepathology in underprivileged countries with poor infrastructure and low health-care budget is a difficult task. On the other hand these countries would mostly benefit by introducing telemedicine/telepathology. In our experience it is possible to build an efficient telepathology/teleradiology network using analogue telephone links and still image transmission, and a store and forward mode of operation. This experience is based on the application of telepathology in Croatia for seven years leading to a national teleradiology network. In this paper the ideas, development and software solutions in the process of establishing a national telepathology and teleradiology network are highlighted.     

Combining dynamic and static robotic telepathology: a report on 184 consecutive cases of frozen sections, histology and cytology.

The aim of this paper is to describe the experiments carried out to evaluate the diagnostic efficacy of a dynamic-robotic telepathology system for the delivery of pathology services to distant hospitals. The system provides static/dynamic features and the remote control of a robotized microscope over 4 ISDN lines. For evaluation purposes, 184 consecutive cases of frozen sections (60), gastrointestinal pathology (64), and urinary cytology (60) have been diagnosed at a distance using the system, and the telediagnosis obtained in this way has been compared with the traditional microscopic diagnosis. Diagnostic agreement ranged from 90% in urinary cytology to 100% in frozen sections. The results obtained suggest that such a system can be considered a useful tool for supporting the pathology practice in isolated hospitals.     

Informational aspects of telepathology in routine surgical pathology.

Application of computer and telecommunication technology calls serious challenges in routine diagnostic pathology. Complete data integration, fast access patients' data to usage of diagnosis thesaurus labeled with standardized codes and free text supplements, complex inquiry of the data contents, data exchange via teleconsultation and multilevel data protection are required functions of an integrated information system. Increasing requirement for teleconsultation transferring a large amount of multimedia data among different pathology information systems raises new questions in telepathology. Creation of complex telematic systems in pathology requires efficient methods of software engineering and implementation. Information technology of object-oriented modeling, usage of client server architecture and relational database management systems enables more compatible systems in field of telepathology. The aim of this paper is to present a practical example how to unify text based database, image archive and teleconsultation in a frame of an integrated telematic system and to discuss the main conceptual questions of information technology of telepathology.     

Telepathology in emerging countries pilot project between Italy and Egypt

Pathological examination includes gross & microscopic examinations at different magnification. Through the steps of examination, we obtain many images that can be used for telepathology. Telepathology is the practice of pathology at a distance, viewing images on a monitor rather than directly through a light microscope. It can be used for primary diagnosis, second opinion, quality assurance and distance learning. Telepathology is classified into Static, Dynamic, Hybrid and Whole Slide Imaging (WSI). We have a successful experience in Egypt in applying the static & dynamic techniques in a pilot project between the Italian Hospital in Cairo (NPO) and the Civico Hospital in Palermo. This project began in 2003 and continued till now. From the second year 2004, Ospedale S. Giovanni e Paolo Hospital in Venice, Charing Cross Hospital in London and the University of Pittsburgh Medical Center Health System (UPMC) in the USA participated actively in our project. During the past five years we consulted on many problematic pathological cases with these different specialized pathological centers in Italy, UK & USA. In addition to the highly specialized scientific value of consulting on the cases and exchanging knowledge, we saved a lot of time and money and succeeded in providing our patients with a better medical service.We are now in the process of establishing a Digital Telepathology Center (DTC) in the pathology department, Cairo University, using the latest technique of telepathology which is Whole Slide Imaging (WSI). We believe that it will help us to improve and extend diagnosis for our difficult pathological cases and will facilitate increased E-learning opportunities for staff and students both in Egypt and in the longer term in the wider Eastern Mediterranean.     

Summer spores of birch rust fungus in Papanicolaou smears from healthy mass screening participants

OBJECTIVE: To evaluate the origin and identification of mysterious particles in Papanicolaou smears from healthy, asymptomatic women participating in a local mass screening program. STUDY DESIGN: The material consisted of 16,000 cerricovaginal smears studied at the cytology laboratory of Pathology Laboratory of South-Western Finland Ltd. Unidentified particles were found in four apparently independent smears. All the slides were rescreened, but no further positive cases were found. RESULTS: Several swab samples were collected from the investigation room, but all were negative. Attempts at identification included numerous consultations. A telepathology consultation with the Cellular Division, Armed Forces Institute of Pathology, Washington, D.C., U.S.A., was conducted. Another teleconsultation with the reference laboratoryfor intestinal parasites in Iceland was conducted. Finally, the Aerobiology Unit, University of Turku, was consulted. The aerobiologist suggested that the particles were most probably summer spores of birch rust fungus (Melampsoridium betulinum). To confirm this we obtained a reference specimen of the fungus from the herbarium at the University of Turku. The morphology of the spore particles was identical to that in the cervicovaginal smears, proving that the smears were contaminated with birch rust fungus spores. CONCLUSION: Birch rust is ubiqutitous in Finland. Outside the hospital window there is a wide lawn behind which, at a distance of 70 m, there is a forest of birch trees. It is most likely that the rust spores flew in through the open window, to settle down on the surface of material that was used in sample taking. Airborne dust may cause misleading and surprising artefacts. Protection of specimens and instruments against dust should minimize the problem.     

Development and use of a rule-based pathology expert consultation system

Since histologic sections of pathologically changed tissues (e.g., tumors and inflammations) are highly complex structures, their subjective diagnostic or prognostic interpretation may result in a lack of interobserver and intraobserver agreement. Rule-based expert systems have the advantages that they require precise representation of the problem and can be used quickly and efficiently, even if the user is not acquainted with the special field concerned. Because of these and other advantages, a rule-based "Pathology Expert Consultation System" (PECS) is under development for the assessment of different premalignancies, malignancies and noncancerous conditions. In addition to supporting diagnosis making, the expert system can infer stage, type and grade, can check for inconsistencies in the answers and can predict the prognosis of an individual patient. PECS permits total integration of information contained in database, worksheet and text files with the rules and other control structures inherent in the rule base. The consultation can be interrupted to display a graph; when the user dismisses the graph, the consultation will resume where it left off or will move to another part of the system (if desired). If the user asks why a question is raised, the system will answer with a textual, graphic or combined explanation. The construction and use of the PECS expert system is discussed. Its initial applications to tumors of the lung, breast and endometrium have shown it to have both educational and clinical significance.