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.     

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.     

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.     

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.     

Legal aspects of telepathology.

In some legal surroundings telepathology is considered a breach of registrational barriers. The recommendation of the G 8 states in Europe for required legislation in telemedicine suggests to recognise that the localization of the remote health care professional defines the site not only of licensure but also of liability. This approach must be considered helpful, since it can solve many problems brought about by the doubtful results of private international law and conventions like the European Union (EU) and Lugano Convention. Under today's conditions in private international law it must be considered essential to agree upon a choice of law and stipulate a court of jurisdiction when doing telepathology. However, the opposing aims of insuring the patients claims and avoiding jurisdictions that exceed the local expectations of the medical professional must be reconciled. Data protection and data security are other crucial topics that require attention. Generally speaking, the principles of minimum data exchange, anonymity, pseudonymity and cryptography must be established as a basis for all telepathology procedures. Only when personal data is needed, its use can be legitimated. Written consent of the patient is advised. To guarantee a cross-border security level the regulations of the EU-Data Protection Directive need to be transformed into national law. In practise, cross-border dataflow shall only take place where the security level can be maintained even within the other country. Finally, reimbursement questions must be answered to establish a sound economical basis for telepathology. The spatial distance between the participants may yield the question, whether the service has been rendered to an extent necessary and sufficient for reimbursement. If reimbursement takes place on a cross-border or cross-regional level, severe disturbances of the health systems can occur. Regulation schemes or treaties need therefore to be developed to avoid such disturbances and encompass mutual standards of care as well as methods to balance reimbursement.     

甲状腺组织冷冻切片的优化

目的优化冷冻切片的关键条件,以期提高甲状腺组织冷冻制片效率、切片质量与染色效果。方法收集术中新鲜送检的甲状腺标本,通过对比实验,比较冷冻切片制作环节中取材厚度、速冻方法与染色方法等因素对制片质量的影响。结果甲状腺组织冷冻切片取材厚度以0.2~0.3cm为佳;预先制作“冰垫”的托头并于上方加盖冷冻冰锤,有利于提高速冻效率、提高组织结构清晰度、减少组织块崩裂、减少冰晶、减少裂隙;机染有利于提高染色优良率并减少染色时间。结论选择适当的取材厚度、优化速冻方法、采用优质的染色方法,可显著提高甲状腺组织冷冻切片的制片质量,为精准的术中病理诊断奠定基础。     

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.     

Teleeducation and telepathology for open and distance education.

Our experience in creating and using telepathology system and multimedia database for education is described. This program packet currently works in the Department of Pathology of University Medical School in Poznan. It is used for self-education, tests, services and for the examinations in pathology, i.e., for dental students and for medical students in terms of self-education and individual examination services. The system is implemented on microcomputers compatible with IBM PC and works in the network system Netware 5.1. Some modules are available through the Internet. The program packet described here accomplishes the TELEMIC system for telepathology, ASSISTANT, which is the administrator for the databases, and EXAMINATOR, which is the executive program. The realization of multi-user module allows students to work on several working areas, on random be chosen different sets of problems contemporary. The possibility to work in the exercise mode will image files and questions is an attractive way for self-education. The standard format of the notation files enables to elaborate the results by commercial statistic packets in order to estimate the scale of answers and to find correlation between the obtained results. The method of multi-criterion grading excludes unlimited mutual compensation of the criteria, differentiates the importance of particular courses and introduces the quality criteria. The packet is part of the integrated management information system of the department of pathology. Applications for other telepathological systems are presented.     

Organizational model for a telepathology system

The technological development of telemedicine has performed important progress, assuming a diagnostic relief role inside of the processes. Among the fields in fast evolution, telepathology is placed among those of greater interest. Up to some years ago, telepathology allowed us to observe at a distance and in real time, histological or cytological slides through the Internet, using a motorized microscope (dynamic telepathology). Currently, telepathology has completed an important step in ahead being possible to digitize completely a slide and to store it. This allows observation of the whole surface of histological or cytological slides remotely with a customary PC, without human intervention (virtual slide). The described systems have exclusive characteristics, so that a "hybrid system" supporting both technologies, turns out to be the best solution applicable in a wide range program. In order to realize the theoretical aspects previously described, we report an organizational model practicable and applicable to a territory in which three hospitals operate. An essential prerequisite in order to arrange an efficient telepathology system turns out to be one structured data transmission network, equipped with elevated guaranteed bandwidth, and one consolidated experience in the registration and management of digital images.     

Acceptance of telepathology in daily practice.

The availability of pathology services differs greatly in our environment. Although pathology would be especially suitable for being practised at a distance by transporting digital image information, the spread of telepathology into everyday work still is relatively slow. The article describes the situation of diffusion of this innovative technology by reviewing the literature and discussing this in context to data based on questionnaires dealing with the acceptance of telepathology. The current situation of telepathology can be discussed by five items for innovation spead: (1) communication and influence; (2) economic costs and benefits; (3) knowledge barriers and learning; (4) feasibility of techniques offered for the demands of the users; (5) clarification of the legal status and other factors concerning international collaboration. All these head lines do not represent realistic obstacles for the more widespread use of telepathology. The real drawbacks may therefore be found behind certain professional habits of pathologists. The most important causes may be that (a) telediagnosis is not as easy as it may seem at the first glance; (b) telepathology is seen as a potential highway to a world-wide competition of pathology service providers. As soon as these mostly unjustified prejudices are corrected and telepathology is percepted as additional technique in pathology, it will become a diagnostic tool as common and as useful as the telephone.     

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.     

Diagnosis of congenital heart malformations--possibilities for the employment of telepathology.

GOAL: In a study of 10 autopsy cases with congenital cardiac malformations we investigated whether obtaining a second opinion by means of telepathology could satisfy quality standards for the diagnosis of cardiac malformations and what the advantages and disadvantages of such a procedure might be. MATERIAL: The investigatory samples were 10 formalin-fixed hearts with complex malformations from 9 fetuses and one newborn on which autopsies had been performed at the Pathological Institute of the Charité Hospital. The requests for a second opinion, which included text and image data, were sent in the form of Microsoft PowerPoint presentations to 5 experts in 4 countries. Per case the number of images that were sent was between 3 and 7. The size of the files was between 439 and 942 kb. The time required for preparation of the cases for sending them to the specialists was between 1 and 2 hours: this encompassed the time for putting the notation on the images, compressing them, creating a file that included both the images and the clinical data and then sending the case file. RESULTS: All 10 cardiac malformations were correctly identified. In 8 of the 10 cases at least one expert had questions. After these questions had been answered and further images had been sent final correct diagnoses were made in all cases. All experts said that the quality of the images was very good. Use of a standardized findings questionnaire, which also included the marking of anatomic structures and of pathological findings in the images, proved useful. Standardized findings forms facilitate orientation during interpretation of the cases and should be used generally to avoid misunderstandings in telepathological communication. CONCLUSIONS: In general it is possible to obtain an effective and reliable diagnosis of congenital heart malformations by means of telepathology. It is far quicker to get a second opinion by this means than by conventional means.     

Cytodiagnosis of 112 salivary gland lesions. Correlation with histologic and frozen section diagnosis.

Aspirates of 112 cases of salivary gland lesions with histologic correlation were reviewed. Fifty-five cases (49%) had frozen sections made. The 112 cases included 76 cases of benign lesions (31 cases of pleomorphic adenoma, 19 of Warthin's tumor and 26 of nonneoplastic lesions), 22 of primary salivary gland malignancy and 14 of metastatic malignant lesions. The overall accuracy in diagnosing benign and malignant lesions was 95%. The accuracy in diagnosing the exact category of neoplastic lesions was 70%. The diagnostic sensitivity for malignant lesions was 86% and the specificity, 99%. There was one false positive, in which a pleomorphic adenoma was diagnosed as small cell carcinoma. Five false-negative cases were encountered that were due to underdiagnosis of mucoepidermoid carcinoma and adenoid cystic carcinoma. The smears were reviewed, and the diagnostic pitfalls are discussed. A comparison of the cytodiagnosis and frozen section diagnosis was made. In frozen sections there were two false negatives, and two diagnoses were deferred. The overall diagnostic accuracy was 91%. The accuracy in diagnosing the exact category of neoplastic disease was 77%. The diagnostic sensitivity for malignant disease was 70% and specificity, 100%. Frozen section, however, did supplement the fine needle aspiration diagnosis in 13 cases.     

Recent developments and present status of telepathology.

Telepathology which is the diagnostic work of a pathologist at a distance has been developed to routine application within the last ten years. It can be classified in relation to application, technical solutions, or performance conditions. Diagnostic pathology performance distinguishes primary diagnosis (for example, frozen section statement) from secondary diagnosis (for example, expert consultation) and quality assurance (diagnostic accuracy, continuous education and training). Applications comprise (a) frozen section service; (b) expert consultations; (c) remote control measurements; and (d) education and training. The technical solutions distinguish active (remote control, live imaging) systems from passive (conventional microscope handling, static imaging), and the performance systems with interactive (on-line, live imaging) use from those with passive (offline, static imaging) practice. Intra-operative frozen section service is mainly performed with remote control systems; whereas expert consultations and education/training are commonly based upon Internet connections with static imaging in an off-line mode. The image quality, transfer rates, and screen resolution of active and passive telepathology systems are sufficient for an additional or primary judgment of histological slides and cytological smears. From the technical point of view, remote control telepathology requires a fast transfer and at least near on-line judgement of images, i.e., image acquisition, transfer and presentation can be considered one performance function. Thus, image size, line transfer rate and screen resolution define the practicability of the system. In expert consultation, the pixel resolution of images and natural color presentation are the main factors for diagnostic support, whereas the line transfer rate is of minor importance. These conditions define the technical compartments, especially size and resolution of camera and screen. The performance of commercially available systems has reached a high quality standard. Pathologists can be trained in a short time and use the systems in a routine manner. Several telepathology systems have been implemented in large Institutes of Pathology which serve for frozen section diagnosis in small hospitals located in the local area. In contrast, expert consultation is mainly performed with international connections. There is a remarkable increase of expert consultations by telepathology according to the experiences of the Armed Forces Institute of Pathology or the Department of Pathology, Thoraxklinik, Heidelberg. In expansion of these experiences, a "globalization" of telepathology can be expected. Telepathology can be used to shrink the period necessary for final diagnosis by request for diagnostic assistance to colleagues working in appropriate related time zones. Telepathology is, therefore, not a substitute of conventional diagnostic procedures but a real improvement in the world of pathology.     

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.     

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.     

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.