When geographical distance poses as a barrier, telepathology is designed to offer pathologists the opportunity to replicate their normal activities by using an alternative means of practice. The rapid progression in technology has greatly influenced the appeal of telepathology and its use in multiple domains. To that point, telepathology systems help to afford teleconsultation services for remote locations, improve the workload distribution in clinical environments, measure quality assurance, and also enhance educational programs. While telepathology is an attractive method to many potential users, the resource requirements for digitizing microscopic specimens have hindered widespread adoption. The use of image compression is extremely critical to help advance the pervasiveness of digital images in pathology. For this research, we characterize two different methods that we use to assess compression of pathology images. Our first method is characterized by the fact that image quality is human-based and completely subjective in terms of interpretation. Our second method is characterized by the fact that image analysis is introduced by using machine-based interpretation to provide objective results. Additionally, the objective outcomes from the image analysis may also be used to help confirm tumor classification. With these two methods in mind, the purpose of this dissertation is to quantify the effects of image compression on data interpretation as seen by human experts and a computerized algorithm for use in telepathology.

Yuan, Qin. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 112-119). / Abstracts in English and Chinese. / Acknowledgements --- p.III / Publications --- p.V / List of Abbreviations --- p.VI / List of Figures --- p.VII / List of Tables --- p.VIII / Abstract in English --- p.IX / Abstract in Chinese --- p.XII / Table of Contents --- p.XIII / Chapter CHAPTER1 I --- NTRODUCTION --- p.1 / Chapter 1.1 --- What is telemedicine --- p.1 / Chapter 1.2 --- What is telepathology --- p.4 / Chapter 1.2.1 --- Types of telepathology system --- p.7 / Chapter 1.2.2 --- Main events in the development of telepathology --- p.9 / Chapter 1.2.3 --- Diagnostic accuracy in telepathology and telecytology --- p.12 / Chapter 1.2.4 --- Applications of telepathology --- p.18 / Chapter 1.2.4.a --- Remote primary diagnosis --- p.18 / Chapter 1.2.4.b --- Remote expert consultation --- p.19 / Chapter 1.2.4.c --- "Image libraries, databases and archiving" --- p.20 / Chapter 1.2.4.d --- Quality assurance --- p.20 / Chapter 1.2.4.e --- Remote teaching and training --- p.21 / Chapter 1.3 --- Technical aspects of telepathology --- p.24 / Chapter 1.3.1 --- Image presentation --- p.24 / Chapter 1.3.2 --- Image acquisition and display --- p.25 / Chapter 1.3.3 --- Image compression --- p.27 / Chapter 1.3.4 --- Networking and line connections --- p.29 / Chapter 1.3.4.a --- Public (analog) telephone network --- p.29 / Chapter 1.3.4.b --- Integrated services digital network (ISDN) --- p.30 / Chapter 1.3.4.c --- Computer network --- p.30 / Chapter 1.3.4.d --- Asynchronous transfer mode (ATM) --- p.31 / Chapter 1.4 --- Legal and ethical aspects --- p.32 / Chapter 1.4.1 --- Licensure of the facility --- p.33 / Chapter 1.4.2 --- Licensure of the pathologist --- p.33 / Chapter 1.4.3 --- Accreditation --- p.34 / Chapter 1.4.4 --- The electronic medical record: privacy --- p.35 / Chapter 1.4.5 --- Malpractice liability --- p.36 / Chapter 1.4.6 --- Reimbursement --- p.38 / Chapter 1.4.7 --- Conclusion --- p.38 / Chapter 1.5 --- Telemedicine and telepathology in China --- p.40 / Chapter 1.6 --- Cytopathology practice in China --- p.42 / Chapter CHAPTER2 --- OBJECTIVES OF STUDY --- p.46 / Chapter CHAPTER3 --- MATERIALS AND METHODS --- p.48 / Chapter 3.1 --- Case materials --- p.48 / Chapter 3.2 --- Static image capture and display --- p.51 / Chapter 3.3 --- Static telecytology study --- p.55 / Chapter 3.4 --- Web-based tutorial program --- p.59 / Chapter 3.4.1 --- Pre-tutorial evaluation --- p.60 / Chapter 3.4.2 --- Cytology tutorial --- p.62 / Chapter 3.4.3 --- Post-tutorial evaluation --- p.66 / Chapter 3.4.4 --- Data analysis --- p.67 / Chapter 3.5 --- Dynamic telecytology study --- p.68 / Chapter 3.5.1 --- Equipment --- p.68 / Chapter 3.5.2 --- Trial design --- p.72 / Chapter 3.5.2a --- Telecytology diagnosis --- p.72 / Chapter 3.5.2b --- Light microscopy diagnosis --- p.73 / Chapter 3.5.2c --- Data analysis --- p.74 / Chapter CHAPTER4 --- RESULTS --- p.75 / Chapter 4.1 --- General information about participating cytology laboratories --- p.75 / Chapter 4.2 --- Static telecytology study --- p.78 / Chapter 4.2.1 --- Telecytology diagnostic agreement --- p.78 / Chapter 4.2.2 --- Confidence of telecytology diagnosis --- p.80 / Chapter 4.2.3 --- "The acceptance of the image quality, time required for each case" --- p.83 / Chapter 4.3 --- Web-based program on cervical cytology --- p.84 / Chapter 4.4 --- Dynamic telecytology study --- p.86 / Chapter 4.4.1 --- Diagnostic accuracy --- p.86 / Chapter 4.4.2 --- Time studies --- p.88 / Chapter 4.4.3 --- Diagnostic certainty --- p.89 / Chapter 4.4.4 --- Image quality --- p.91 / Chapter CHAPTER5 --- DISCUSSION --- p.92 / Chapter 5.1 --- Static image telecytology study linking 14 Mainland China hospitals --- p.93 / Chapter 5.2 --- Problems encountered in setting up links with Mainland China --- p.97 / Chapter 5.3 --- Web-based tutorial programme for remote teaching --- p.100 / Chapter 5.4 --- Dynamic image telecytology study for immediate diagnosis at a distance --- p.103 / Chapter 5.5 --- Limitations of this study --- p.105 / Chapter 5.6 --- Concluding remarks --- p.108 / REFERENCES --- p.112

Telepathology is defined as the practice of pathology at a distance using video imaging and telecommunications. In this thesis we address the two main technology challenges in implementing telepathology, viz. compression and transmission of digital pathology images. One of the barriers to telepathology is the availability and the affordability of high bandwidth communication resources. High bandwidth links are required because of the large size of the uncompressed digital pathology images. For efficient utilization of available bandwidth, these images need to be compressed. However aggressive image compression may introduce objectionable artifacts and result in an inaccurate diagnosis. This discussion helps us to identify two main design challenges in implementing telepathology, 1. Compression: There is a need to develop or select an appropriate image compression algorithm and an image quality criterion to ensure maximum possible image compression, while ensuring that diagnostic accuracy is not compromised. 2. Transmission: There is a need to develop or select a smart image transmission scheme which can facilitate the transmission of the compressed image to the remote pathologist without violating the specified bandwidth and delay constraints. We addressed the image compression problem by conducting subjective tests to determine the maximum compression that can be tolerated before the pathology images lose their diagnostic value. We concluded that the diagnostically lossless compression ratio is at least around 5 to 10 times higher than the mathematically lossless compression ratio, which is only about 2:1. We also set up subjective tests to compare the performance of the JPEG and the JPEG 2000 compression algorithms which are commonly used for compression of medical images. We concluded that JPEG 2000 outperforms JPEG at lower bitrates (bits/pixel), but both the algorithms perform equally well at higher bitrates. We also addressed the issue of image transmission for telepathology by proposing a two-stage transmission scheme, where coarse image information compressed at diagnostically lossless level is sent to the clients at the first stage, and the Region of Interest is transmitted at mathematically lossless compression levels at the second stage, thereby reducing the total image transmission delay.

Introduction: We describe the use of telepathology in countries with restricted resources using two diagnosis assistance systems (Isabel and Memem7) in addition to the diagnoses made by experts in pathology via the iPath-Network. Methods: A total of 156 cases, largely from Afghanistan, were analysed; 18 cases had to be excluded because of poor image quality. Results: Of the remaining 138 cases (100%), a responsible physician provided a tentative diagnosis for 61.6% of them.With a diagnosis from a consultant pathologist, it was then possible to make a definite diagnosis in 84.8% of cases on the basis of images taken from hematoxylin and eosin staining sections alone. The use of the diagnosis assistance systems resulted in an ordered list of differential diagnoses in 82.6% (IsabelHealth) and in 74.6% (Memem7) of cases, respectively. Adding morphological terminology reduced the list of possible diagnoses to 52.2% (72 cases, Memem7), but improved their quality. Discussion: In summary, diagnosis assistance systems are promising approaches to provide physicians in countries with restricted resources with lists of probable differential diagnoses, thus increasing the plausibility of the diagnosis of the consultant pathologist.

Ziel der vorliegenden Arbeit ist es, die Frage nach Eignung der Technik, des Aufwands, der Schulung und der Vor- und Nachteile eines Einsatzes der Telepathologie in der Schnellschnitt-Diagnostik zu analysieren. Weltweit wurden verschiedene Telepathologiesysteme entwickelt, die zum Teil für den Schnellschnitt verwendet werden können. Auch an der Charité entstanden mit dem 1.ATM-System, 2.dem TPS-System und 3.dem TELEMIC-System, drei technisch völlig unterschiedliche Systeme. Diese Systeme wurden anhand einer retrospektiven Studie hinsichtlich ihrer Einsatzfähigkeit in der telepathologische Schnellschnitt-Diagnostik untersucht. Um die Systeme untereinander vergleichen zu können, wurden 124 histologische Schnellschnittpräparate aus dem Jahr 1999 herausgesucht (ausschließlich Brustgewebe), die von vier erfahrenen Pathologen mit jedem System erneut bearbeitet wurden. Qualitativ wurden mit dem ATM- und dem TPS-System gleichwertige Ergebnisse wie in der konventionellen Schnellschnitt-Diagnostik erreicht. Das TELEMIC-System war qualitativ aufgrund der hohen Rate von Rückweisungen den anderen Systemen und dem konventionellen Schnellschnitt deutlich unterlegen. Bei den Diagnosezeiten zeigte sich eine leichte Unterlegenheit des TPS-Systems gegenüber dem konventionellen Schnellschnitt. Da es jedoch insbesondere als Möglichkeit der Ferndiagnose eingesetzt wird, fallen die bei der konventionellen Schnellschnitt-Diagnostik nötigen Transportzeiten durch einen Kurier weg. Das ATM-System und das TELEMIC-System sind auch ohne Zurechnung der Transportzeiten zeitlich zum konventionellen Schnellschnitt vergleichbare Systeme. / Target of the available work is it, the question about suitability of the technique, the expenditure, to analyze the training and the pro and cons of an application of the Telepathologie on fresh frozen diagnostics. World-wide different Systems for telepathology were developed, which can be used partially for the fresh frozen diagnostics. At the Charité were developed three technically completely different systems: 1.ATM-System, 2.TPS system and 3.TELEMIC system, These systems were examined on the basis a retrospective study regarding their serviceability on telepathologische fresh frozen diagnostics. In order to be able to compare the systems among themselves, 124 histological fresh frozen preparations were picked out from the year 1999 (excluding chest tissues), which were again processed by four experienced pathologists with each system. Qualitatively with ATM and TPS system equivalent results as on were achieved conventional fresh frozen diagnostics. The TELEMIC system was qualitatively inferior for the other systems and the conventional fresh frozen diagnostics due to the high rate of rejections. With the diagnostic times an easy inferiority of the TPS system showed up in relation to the conventional fresh frozen diagnostics. Since it is used however in particular as possibility of the remote diagnostics, the feed times necessary with the conventional fresh frozen diagnostics are omitted by a courier. The ATM system and the TELEMIC system are also without addition of the feed times temporally to the conventional fresh frozen diagnostics comparable systems.

Objective: In this study, the efficiency of telemedical consulting with regard to fine needle aspirates from space-occupying lesions (SOLs) of the liver is investigated for the first time. Study Design: The study includes fine needle aspirations from 62 patients, 33 with hepatocellular carcinoma (HCC) and 29 with non-hepatic tumors. Using the Internetbased iPath system, the initial pathologist submitted 1–8 images from smears and cell block sections. One consultant assessed the cytological and another one the histological images. Both made their diagnoses independent of each other. A final diagnosis was made by immunochemistry of cell block sections. The cytological images were analyzed retrospectively for the occurrence of the most typical HCC indicators. The number of these indicators was related to the initial diagnoses of the three pathologists, and possible reasons for diagnostic errors were analyzed based on this analysis. Results: The accuracy of the preliminary telemedical diagnoses regarding HCC was 82.0% for the cytological images and 87.7% for the histological images. Most of the false diagnoses occurred in tumors with unusual cytological and histological patterns. Conclusions: Telemedical consulting is a valuable tool to obtain a second opinion. However, for improvement of the diagnosis of HCC, supplementary immunochemical tests are necessary.

Aufgrund der rasanten technischen Entwicklung im Bereich der pränatalen Diagnostik in den letzten Jahren werden mehr angeborene Fehlbildungen zu einem früheren Zeitpunkt der Schwangerschaft und detaillierter erkannt. Das führt dazu, dass die zur Autopsie gelangenden Feten zunehmend kleiner sind und komplexere Befunde aufweisen. Gleichzeitig werden die genetischen Ursachen von mehr Erkrankungen, Fehlbildungen und Syndromen aufgedeckt, so dass die DNA-Diagnostik, Chromosomenanlyse u.a. molekulargenetische und biochemische Erkenntnisse die klinisch-genetische Diagnostik zunehmend ergänzen. Durch Festlegung einer gezielten Autopsiestrategie und Nutzung moderner Kommunikationsmittel kann der Pathologe die in den letzten Jahren gestiegenen klinischen Anforderungen erfüllen. Ein Problem ist es jedoch, dass nicht genügend Pathologen auf dem Gebiet der Fetalpathologie spezialisiert sind. Das trifft nicht nur für Deutschland zu, sondern das ist mehr oder weniger eine weltweite Situation. Ein möglicher Lösungsansatz dieses Problems wäre die Nutzung von Softwareprogrammen, die dazu dienen, unerfahrene Pathologen moderne Anleitungen während der Autopsie von Feten zu geben. Das kann mit einer telepathologischen Betreung durch einen Experten auf diesem Gebiet kombiniert werden. Darüberhinaus erlaubt die derzeitige digitalisierte Befunddokumentation den Vergleich aktueller mit gespeicherten Fällen sowie Recherchen und stellt eine gute Basis zur Erstellung von Lehrmaterial dar. / Due to the enormous technical developments in recent years in the area of prenatal ultrasound more malformations are detected in greater detail and at an earlier point in time during pregnancy than in the past. As a result, fetuses of increasingly smaller size and with complex diagnoses are presented for autopsy. At the same time, the genetic causes of ever more diseases, malformations and syndromes are being discovered, so that DNA diagnostics, chromosome analysis and, among others, molecular-genetic and biochemical investigations have come increasingly to complement clinical-genetic diagnostics. Through establishment of a clinically oriented autopsy strategy and the use of modern communication media, pathologists can satisfy the increased clinical demands of recent years. The remaining problem is that we do not have enough pathologists experienced in fetal pathology. This is not only true for Germany, it is more less the situation worldwide. One means of dealing with this problem may be the use of software programs to guide inexperienced pathologists through the modern autopsy procedure. This can be combined with the use of telepathological advise given by an expert in the field. Over and above this, digitized documentation of findings can be used in research, which allows the comparison of current with previously saved cases and presents a good basis for the development of education material.

Aufgrund der rasanten technischen Entwicklung im Bereich der pränatalen Diagnostik in den letzten Jahren werden mehr angeborene Fehlbildungen zu einem früheren Zeitpunkt der Schwangerschaft und detaillierter erkannt. Das führt dazu, dass die zur Autopsie gelangenden Feten zunehmend kleiner sind und komplexere Befunde aufweisen. Gleichzeitig werden die genetischen Ursachen von mehr Erkrankungen, Fehlbildungen und Syndromen aufgedeckt, so dass die DNA-Diagnostik, Chromosomenanlyse u.a. molekulargenetische und biochemische Erkenntnisse die klinisch-genetische Diagnostik zunehmend ergänzen. Durch Festlegung einer gezielten Autopsiestrategie und Nutzung moderner Kommunikationsmittel kann der Pathologe die in den letzten Jahren gestiegenen klinischen Anforderungen erfüllen. Ein Problem ist es jedoch, dass nicht genügend Pathologen auf dem Gebiet der Fetalpathologie spezialisiert sind. Das trifft nicht nur für Deutschland zu, sondern das ist mehr oder weniger eine weltweite Situation. Ein möglicher Lösungsansatz dieses Problems wäre die Nutzung von Softwareprogrammen, die dazu dienen, unerfahrene Pathologen moderne Anleitungen während der Autopsie von Feten zu geben. Das kann mit einer telepathologischen Betreung durch einen Experten auf diesem Gebiet kombiniert werden. Darüberhinaus erlaubt die derzeitige digitalisierte Befunddokumentation den Vergleich aktueller mit gespeicherten Fällen sowie Recherchen und stellt eine gute Basis zur Erstellung von Lehrmaterial dar. / Due to the enormous technical developments in recent years in the area of prenatal ultrasound more malformations are detected in greater detail and at an earlier point in time during pregnancy than in the past. As a result, fetuses of increasingly smaller size and with complex diagnoses are presented for autopsy. At the same time, the genetic causes of ever more diseases, malformations and syndromes are being discovered, so that DNA diagnostics, chromosome analysis and, among others, molecular-genetic and biochemical investigations have come increasingly to complement clinical-genetic diagnostics. Through establishment of a clinically oriented autopsy strategy and the use of modern communication media, pathologists can satisfy the increased clinical demands of recent years. The remaining problem is that we do not have enough pathologists experienced in fetal pathology. This is not only true for Germany, it is more less the situation worldwide. One means of dealing with this problem may be the use of software programs to guide inexperienced pathologists through the modern autopsy procedure. This can be combined with the use of telepathological advise given by an expert in the field. Over and above this, digitized documentation of findings can be used in research, which allows the comparison of current with previously saved cases and presents a good basis for the development of education material.