Virtual microscopy: high resolution digital photomicrography as a tool for light microscopy simulation

Virtual Microscopy Goes Global: The Images Are Virtual and the Problems Are Real

For the last two centuries, the scholarly education of histology and pathology has been based on technology, initially on the availability of low-cost, high-quality light microscopes, and more recently on the introduction of computers and e-learning approaches to biomedical education. Consequently, virtual microscopy (VM) is replacing glass slides and the traditional light microscope as the main instruments of instruction in histology and pathology laboratories. However, as with most educational changes, there are advantages and disadvantages associated with a new technology. The use of VM for the teaching of histology and pathology requires an extensive infrastructure and the availability of computing devices to all learners, both posing a considerable financial strain on schools and students. Furthermore, there may be valid reasons for practicing healthcare professionals to maintain competency in using light microscopes. In addition, some educators may be reluctant to embrace new technologies. These are some of the reasons why the introduction of VM as an integral part of histology and pathology instruction has been globally uneven. This paper compares the teaching of histology and pathology using traditional or VM in five different countries and their adjacent regions, representing developed, as well as developing areas of the globe. We identify general and local roadblocks to the introduction of this still-emerging didactic technology and outline solutions for overcoming these barriers.

The Role of Telehealth During the COVID-19 Pandemic Across the Interdisciplinary Cancer Team: Implications for Practice

Objective

This literature review aims to explore the role of telehealth during the COVID-19 pandemic across the interdisciplinary cancer care team.

Data Sources

Electronic databases including CINAHL, MEDLINE, PsychINFO, Scopus, and gray literature were searched using Google Scholar up until September 2020.

Conclusion

Although the safe and effective delivery of cancer care via telehealth requires education and training for health care professionals and patients, telehealth has provided a timely solution to the barriers caused by the COVID-19 pandemic on the delivery of interdisciplinary cancer services. Globally, evidence has shown that telehealth in cancer care can leverage an innovative response during the COVID-19 pandemic but may provide a long-lasting solution to enable patients to be treated appropriately in their home environment. Telehealth reduces the travel burden on patients for consultation, affords a timely solution to discuss distressing side effects, initiate interventions, and enable possible treatment additions and/or changes.

Implications for Nursing Practice

Global public health disasters pose significant and unique challenges to the provision of necessary services for people affected by cancer. Oncology nurses can provide a central contribution in the delivery of telehealth through transformational leadership across all domains and settings in cancer care. Oncology nurses provide the “hub of cancer care” safely embedded in the interdisciplinary team. Telehealth provides a solution to the current global health crisis but could also benefit the future provision of services and broad reach clinical trials.

Modern Imaging Technologies in Toxicologic Pathology: An Overview

Modern imaging technology, now utilized in most biomedical research areas (bioimaging), enables the detection and visualization of biological processes at various levels of the molecule, organelle, cell, tissue, organ and/or whole body. In toxicologic pathology, the impact of modern imaging technology is becoming apparent from digital histopathology to novel molecular imaging for in vivo studies. This overview summarizes recent progresses in digital microscopy imaging and newly developed digital slide techniques. Applications of virtual microscopy imaging are discussed and compared to traditional optical microscopy reading. New generation digital pathology approaches, including automatic slide inspection, digital slide databases and image management are briefly introduced. Commonly used in vivo preclinical imaging technologies are also summarized. While most of these new imaging techniques are still undergoing rapid development, it is important that toxicologic pathologists embrace and utilize these technologies as advances occur.

Screening and dotting virtual slides: A new challenge for cytotechnologists

Digital images are increasingly being used in cytopathology. Whole-slide imaging (WSI) is a digital imaging modality that uses computerized technology to scan and convert entire cytology glass slides into digital images that can be viewed on a digital display using the image viewer software. Digital image acquisition of cytology glass slides has improved significantly over the years due to the use of liquid-based preparations and advances in WSI scanning technology such as automatic multipoint pre-scan focus technology or z-stack scanning technology. Screening cytotechnologists are responsible for every cell that is present on an imaged slide. One of the challenges users have to overcome is to establish a technique to review systematically the entire imaged slide and to dot selected abnormal or significant findings. The scope of this article is to review the current user interface technology available for virtual slide navigation when screening digital slides in cytology. WSI scanner vendors provide tools, built into the image viewer software that allow for a more systematic navigation of the virtual slides, such as auto-panning, keyboard-controlled slide navigation and track map. Annotation tools can improve communication between the screener and the final reviewer or can be used for education. The tracking functionality allows recording of the WSI navigation process and provides a mechanism for confirmation of slide coverage by the screening cytotechnologist as well as a useful tool for quality assurance. As the WSI technology matures, additional features and tools to support navigation of a cytology virtual slide are anticipated.

Virtual slide telepathology workstation of the future: lessons learned from teleradiology

The clinical reading environment for the 21st century pathologist looks very different than it did even a few short years ago. Glass slides are quickly being replaced by digital "virtual slides," and the traditional light microscope is being replaced by the computer display. There are numerous questions that arise however when deciding exactly what this new digital display viewing environment will be like. Choosing a workstation for daily use in the interpretation of digital pathology images can be a very daunting task. Radiology went digital nearly 20 years ago and faced many of the same challenges so there are lessons to be learned from these experiences. One major lesson is that there is no "one size fits all" workstation so users must consider a variety of factors when choosing a workstation. In this article, we summarize some of the potentially critical elements in a pathology workstation and the characteristics one should be aware of and look for in the selection of one. Issues pertaining to both hardware and software aspects of medical workstations will be reviewed particularly as they may impact the interpretation process.

Interactive visualization of multiresolution image stacks in 3D

Conventional microscopy, electron microscopy, and imaging techniques such as MRI and PET commonly generate large stacks of images of the sectioned brain. In other domains, such as neurophysiology, variables such as space or time are also varied along a stack axis. Digital image sizes have been progressively increasing and in virtual microscopy, it is now common to work with individual image sizes that are several hundred megapixels and several gigabytes in size. The interactive visualization of these high-resolution, multiresolution images in 2D has been addressed previously [Sullivan, G., and Baker, R., 1994. Efficient quad-tree coding of images and video. IEEE Trans. Image Process. 3 (3), 327-331]. Here, we describe a method for interactive visualization of multiresolution image stacks in 3D. The method, characterized as quad-tree based multiresolution image stack interactive visualization using a texel projection based criterion, relies on accessing and projecting image tiles from multiresolution image stacks in such a way that, from the observer's perspective, image tiles all appear approximately the same size even though they are accessed from different tiers within the images comprising the stack. This method enables efficient navigation of high-resolution image stacks. We implement this method in a program called StackVis, which is a Windows-based, interactive 3D multiresolution image stack visualization system written in C++ and using OpenGL. It is freely available at http://brainmaps.org.

Internet-enabled high-resolution brain mapping and virtual microscopy

Virtual microscopy involves the conversion of histological sections mounted on glass microscope slides to high-resolution digital images. Virtual microscopy offers several advantages over traditional microscopy, including remote viewing and data sharing, annotation, and various forms of data mining. We describe a method utilizing virtual microscopy for generation of internet-enabled, high-resolution brain maps and atlases. Virtual microscopy-based digital brain atlases have resolutions approaching 100,000 dpi, which exceeds by three or more orders of magnitude resolutions obtainable in conventional print atlases, MRI, and flat-bed scanning. Virtual microscopy-based digital brain atlases are superior to conventional print atlases in five respects: (1) resolution, (2) annotation, (3) interaction, (4) data integration, and (5) data mining. Implementation of virtual microscopy-based digital brain atlases is located at BrainMaps.org, which is based on more than 10 million megapixels (35 terabytes) of scanned images of serial sections of primate and non-primate brains with a resolution of 0.46 microm/pixel (55,000 dpi). The method can be replicated by labs seeking to increase accessibility and sharing of neuroanatomical data. Online tools offer the possibility of visualizing and exploring completely digitized sections of brains at a sub-neuronal level and can facilitate large-scale connectional tracing, histochemical, and stereological analyses.

The use of virtual microscopy for proficiency testing in gynecologic cytopathology: a feasibility study using ScanScope

CONTEXT

ScanScope software can digitize entire cytology slides.

OBJECTIVE

To test the feasibility of using virtual microscopy methods and "virtual Papanicolaou tests" for proficiency testing (PT) in gynecologic cytopathology.

DESIGN

Two PT exercises were conducted using virtual microscopy. Five cytopathologists and 1 cytotechnologist interpreted images using 2 different schema as follows: (1) the College of American Pathologists graded diagnostic codes (CAP-GDCs) and (2) the Center for Medicare and Medicaid Services test scoring categories (CMS-TSCs). The number of diagnostic errors using the CAP-GDCs and the CMS-TSCs, the mean length of time spent diagnosing each case, and the impressions by the users regarding the facility of the technology and image quality were studied.

RESULTS

In the first PT exercise, the participants provided incorrect diagnoses in 4 to 8 of the 10 test cases using the CAP-GDCs and in 1 to 4 of the 10 test cases using the CMS-TSCs. In the second PT exercise, the number of errors decreased to 1 to 6 using the CAP-GDCs and to 0 to 6 using the CMS-TSCs. The results did not achieve statistical significance. The mean time of 9.4 minutes spent per case in the second PT exercise was significantly shorter than the 14.4 minutes spent per case in the first PT exercise (P < .001). The ease of use of the software and the image quality were scored by all participants as 3+ or as 4+.

CONCLUSIONS

This preliminary study shows that virtual microscopy and virtual Papanicolaou tests prepared using ScanScope may provide effective tools for PT. Technical issues that require further investigation are discussed.

[Digitalized imaging pathology: application to quality control in cancer diagnosis]

OBJECTIVES

To test a double histology reading system based on digitalized imaging for cancer diagnosis.

MATERIAL AND METHODS

Pathology images of cancer diagnosis material were produced in real time by a digital imaging system integrated into the laboratory data processing system. Over a 30-day period, second readings were performed using the digitalized images. Cases with second readings were classified according to the aspect on the digitalized images as malignant tumor with histological type, malignant tumor with no other precision, and doubtful malignancy.

RESULTS

During the study period, 204 cases of cancer were diagnosed, including 178 with digitalized imaging (87%). Among the digitalized cases, 119 (67%) were classified as malignant tumor with histological type, 53 (30%) as malignant tumor with no other precision, and 6 (3%) as doubtful malignancy. The histology material of these latter cases were reviewed and corresponded to malignant tumors. Approximately 2 hours per week were devoted to the second readings.

CONCLUSION

A integrated digitalized imaging system can participate in quality control of cancer diagnosis by allowing rapid efficacious second readings.

Virtual Microscopy:Applications to Hematology

Virtual microscopy is the simulation of microscopy over a computer network. A virtual slide is a giant digital image file of a glass slide that can be displayed, panned, zoomed, and focused in a virtual slide viewer on a computer screen. Virtual slides represent a revolutionary advance over glass slides. They are easy to file, store, retrieve, annotate, and mark and can be preserved indefinitely. Furthermore, they are easy to duplicate and distribute and can be integrated into electronic patient records. Large virtual slides can be readily transmitted to users over a standard broadband connection. With the recent introduction of viewers that can focus virtual slides, virtual microscopy can simulate all the functions of real microscopy. Virtual microscopy has significant advantages over real microscopy in education and in proficiency testing. In education, virtual microscopy enables "anytime, anywhere" learning and has been favorably received by students and teachers. In proficiency surveys, all users view the same image, virtual slides are easy to distribute, and the slides do not deteriorate. Potential applications for hematology proficiency surveys include blood and bone marrow morphology, differential cell counts, cytochemistry and immunocytochemistry, detection of malarial parasites, and other tests. Virtual microscopy enables proficiency surveys of critical clinical parameters, such as the bone marrow blast count, and implementation of "locate and identify" exercises. It is conceivable that with the next generation of technological developments, virtual microscopy can be extended to diagnostic applications. Important goals are to minimize slide file size without loss of relevant detail, to establish diagnostic equivalence, and to automate virtual slide capture with high throughput for integration into laboratory information systems. Key factors that will drive implementation include user-friendliness, cost, data storage requirements, and throughput speed. Implementation may have constructive effects on teaching and learning, the peer-to-peer consultative process, and diagnostic accuracy and performance.

An array microscope for ultrarapid virtual slide processing and telepathology. Design, fabrication, and validation study

This paper describes the design and fabrication of a novel array microscope for the first ultrarapid virtual slide processor (DMetrix DX-40 digital slide scanner). The array microscope optics consists of a stack of three 80-element 10 x 8-lenslet arrays, constituting a "lenslet array ensemble." The lenslet array ensemble is positioned over a glass slide. Uniquely shaped lenses in each of the lenslet arrays, arranged perpendicular to the glass slide constitute a single "miniaturized microscope." A high-pixel-density image sensor is attached to the top of the lenslet array ensemble. In operation, the lenslet array ensemble is transported by a motorized mechanism relative to the long axis of a glass slide. Each of the 80 miniaturized microscopes has a lateral field of view of 250 microns. The microscopes of each row of the array are offset from the microscopes in other rows. Scanning a glass slide with the array microscope produces seamless two-dimensional image data of the entire slide, that is, a virtual slide. The optical system has a numerical aperture of N.A.= 0.65, scans slides at a rate of 3 mm per second, and accrues up to 3,000 images per second from each of the 80 miniaturized microscopes. In the ultrarapid virtual slide processing cycle, the time for image acquisition takes 58 seconds for a 2.25 cm2 tissue section. An automatic slide loader enables the scanner to process up to 40 slides per hour without operator intervention. Slide scanning and image processing are done concurrently so that post-scan processing is eliminated. A virtual slide can be viewed over the Internet immediately after the scanning is complete. A validation study compared the diagnostic accuracy of pathologist case readers using array microscopy (with images viewed as virtual slides) and conventional light microscopy. Four senior pathologists diagnosed 30 breast surgical pathology cases each using both imaging modes, but on separate occasions. Of 120 case reads by array microscopy, there were 3 incorrect diagnoses, all of which were made on difficult cases with equivocal diagnoses by light microscopy. There was a strong correlation between array microscopy vs. "truth" diagnoses based on surgical pathology reports. The kappa statistic for the array microscopy vs. truth was 0.96, which is highly significant (z=10.33, p <0.001). There was no statistically significant difference between rates of agreement with truth between array microscopy and light microscopy (z=0.134, p >0.05). Array microscopy and light microscopy did not differ significantly with respect to the number/percent of correct decisions rendered (t=0.552, p=0.6376) or equivocal decisions rendered (t=2.449, p=0.0917). Pathologists rated 95.8% of array microscopy virtual slide images as good or excellent. None were rated as poor. The mean viewing time for a DMetrix virtual slide was 1.16 minutes. The DMetrix virtual slide processor has been found to reduce the virtual slide processing cycle more than 10 fold, as compared with other virtual slide systems reported to date. The virtual slide images are of high quality and suitable for diagnostic pathology, second opinions, expert opinions, clinical trials, education, and research.

Digital photography: a primer for pathologists

The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high-resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge-coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than 2,500 dollars that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11x14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio-enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare "zoomable" panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data.

Virtual microscopy as a tool for proficiency testing in cytopathology: a model using multiple digital images of Papanicolaou tests

BACKGROUND

Modern digital cameras can acquire images from cytologic slides at sufficient resolution to allow for digital enlargement and scrolling on a video monitor, allowing for the simulation of microscopy using a computer.

OBJECTIVE

The purpose of this study was to develop a tool for proficiency testing in cytopathology using multiple digital images of Papanicolaou tests.

METHODS

Nine images were photographed from each of 10 Papanicolaou tests at x100 optical magnification, 3400 x 2300-pixel resolution, using a light microscope and a digital camera. All images from each case were tiled in a single canvas with Photoshop 4.0 software. Two cytopathologists and 3 cytotechnologists interpreted these "virtual slides" using a computer and graded diagnostic codes (PAP program, College of American Pathologists). Subjects were retested a year later using the glass slides from the same cases and routine microscopy. Both test results, by diagnostic code, were compared with the McNemar test of symmetry.

RESULTS

The 5 test subjects provided 42 and 50 correct diagnostic codes by "virtual microscopy" and light microscopy, respectively. No significant asymmetry in results obtained by virtual microscopy and light microscopy was encountered with the McNemar test of symmetry. All test answers were correctly classified by selection series, using both virtual microscopy and light microscopy, and the responses would have been graded as 100% by current PAP program scoring guidelines. This suggests that virtual microscopy could be used for proficiency testing purposes.

CONCLUSIONS

A simple virtual microscopy method designed to challenge participants to locate and diagnose cells of interest was effective for the administration of standardized proficiency tests. Virtual microscopy methods that rely on single-plane images to locate and diagnose cells of interest could provide effective proficiency testing tools prior to the development of more computationally intensive systems that represent an entire Papanicolaou test at multiple focal planes.

Easy method of capturing microscopical images by using a consumer-type digital camera

Taking pictures of microstructures is difficult, requiring sophisticated cameras coupled by the microscopes. Furthermore, it may not be feasible to find an operating microscope paired with a camera, especially in laboratory conditions. Considering the difficulty of obtaining microscopic photographs in clinical and laboratory settings, this report describes a practical method of digital photography of microstructures using a consumer-type digital camera. The technique can be summarized simply as placing the lens of a consumer-type digital camera over the eyepieces of a surgical microscope, whereby the anatomic structure of interest is focused. The image thus obtained is transferred to the computer, using easily available software programs. The authors conclude that this method is an inexpensive and practical way of capturing photographs of microstructures, obviating the need for using microscopes coupled by the cameras.

Telepathology: current status and future prospects in diagnostic histopathology

Telepathology is the process of diagnostic histopathology performed on digital images viewed on a display screen rather than by conventional glass slide light microscopy. The technology of telepathology has radically improved over the past 5 years so that it is no longer the limiting factor in the diagnostic process. This review looks at the resources needed for dynamic and static telepathology, including image quality, computers and software interfaces, means of transmission and human resources. It critically analyses 32 published trials of telepathology, including some large prospective studies, in all areas of diagnostic histopathology including intraoperative frozen sections, routine and referral cases. New developments, including internet solutions and virtual microscopy, are described and there is analysis of the economics of telepathology within health care systems. The review concludes that all the necessary technology for telepathology is available, there is strong published evidence for a diagnostic accuracy comparable with glass slide diagnosis, in many contexts there is a clear-cut economic argument in favour of telepathology, and that the technique should now be integrated into mainstream diagnostic histopathology.

Practical telepathology using a digital camera and the internet

Digital camera technology has developed rapidly and a large choice of reasonably priced, user-oriented models are now available. These can be used for both macroscopic and microscopic photography with good resolution. Internet transmission of digital images also makes it possible to consult pathologists anywhere in the world. This study tests a simple, fast, and inexpensive method for practical transmission of images for diagnosis using a digital camera and the Internet. Using a commercial digital camera mounted with a phototube adapter to a light microscope (6 images per case on average), 2210 digital images (310 Mb) from 347 cases of gastrointestinal, lung, and uterus specimens were captured. Each image, stored in medium compression JPEG (Joint Photographers Experts Group) format with 1024 x 768 pixel resolution, required approximately 5 seconds to capture after the case had been reviewed and appropriate fields for imaging selected (30 seconds per case on average). The images were transmitted from Samsung Medical Center, Seoul, to Korea University Hospital, Seoul, and John Hunter Hospital, Newcastle, Australia. Transmission was 100% successful with a total upload time of 3 hours for 310 MB of data (31 seconds per case on average). The images were downloaded in 2 hours and viewed on a 17-inch color monitor with a maximal resolution of 1280 x 1024 pixels. Telepathology diagnoses were made with 95% and 97% concurrence by two pathologists at Korea University Hospital and John Hunter Hospital, respectively. We suggest that the current level of commercial technology yields fast, convenient and economical tools for practical telepathology diagnosis.

Transcontinental communication and quantitative digital histopathology via the Internet; with special reference to prostate neoplasia

OBJECTIVE

To describe practical experiences in the sharing of very large digital data bases of histopathological imagery via the Internet, by investigators working in Europe, North America, and South America.

MATERIALS

Experiences derived from medium power (sampling density 2.4 pixels/microm) and high power (6 pixels/microm) imagery of prostatic tissues, skin shave biopsies, breast lesions, endometrial sections, and colonic lesions. Most of the data included in this paper were from prostate. In particular, 1168 histological images of normal prostate, high grade prostatic intraepithelial neoplasia (PIN), and prostate cancer (PCa) were recorded, archived in an image format developed at the Optical Sciences Center (OSC), University of Arizona, and transmitted to Ancona, Italy, as JPEG (joint photographic experts group) files. Images were downloaded for review using the Internet application FTP (file transfer protocol). The images were then sent from Ancona to other laboratories for additional histopathological review and quantitative analyses. They were viewed using Adobe Photoshop, Paint Shop Pro, and Imaging for Windows. For karyometric analysis full resolution imagery was used, whereas histometric analyses were carried out on JPEG imagery also.

RESULTS

The three applications of the telecommunication system were remote histopathological assessment, remote data acquisition, and selection of material. Typical data volumes for each project ranged from 120 megabytes to one gigabyte, and transmission times were usually less than one hour. There were only negligible transmission errors, and no problem in efficient communication, although real time communication was an exception, because of the time zone differences. As far as the remote histopathological assessment of the prostate was concerned, agreement between the pathologist's electronic diagnosis and the diagnostic label applied to the images by the recording scientist was present in 96.6% of instances. When these images were forwarded to two pathologists, the level of concordance with the reviewing pathologist who originally downloaded the files from Tucson was as high as 97.2% and 98.0%. Initial results of studies made by researchers belonging to our group but located in others laboratories showed the feasibility of making quantitative analysis on the same images.

CONCLUSIONS

These experiences show that diagnostic teleconsultation and quantitative image analyses via the Internet are not only feasible, but practical, and allow a close collaboration between researchers widely separated by geographical distance and analytical resources.

Storage and distribution of pathology digital images using integrated web-based viewing systems

CONTEXT

Health care providers have expressed increasing interest in incorporating digital images of gross pathology specimens and photomicrographs in routine pathology reports.

OBJECTIVE

To describe the multiple technical and logistical challenges involved in the integration of the various components needed for the development of a system for integrated Web-based viewing, storage, and distribution of digital images in a large health system.

DESIGN

An Oracle version 8.1.6 database was developed to store, index, and deploy pathology digital photographs via our Intranet. The database allows for retrieval of images by patient demographics or by SNOMED code information.

SETTING

The Intranet of a large health system accessible from multiple computers located within the medical center and at distant private physician offices.

RESULTS

The images can be viewed using any of the workstations of the health system that have authorized access to our Intranet, using a standard browser or a browser configured with an external viewer or inexpensive plug-in software, such as Prizm 2.0. The images can be printed on paper or transferred to film using a digital film recorder. Digital images can also be displayed at pathology conferences by using wireless local area network (LAN) and secure remote technologies.

CONCLUSIONS

The standardization of technologies and the adoption of a Web interface for all our computer systems allows us to distribute digital images from a pathology database to a potentially large group of users distributed in multiple locations throughout a large medical center.

Internet teleconferencing method for telepathology consultations from lung and heart transplant patients

Current Internet-based teleconferencing techniques allow a referring pathologist to transmit real-time images from a microscope to a consultant, while maintaining a verbal conversation using Internet telephony. In our study, 50 randomly selected transbronchial biopsies from lung allograft recipients and 58 randomly selected endomyocardial biopsies from heart transplant patients were diagnosed by consultant pathologists using Internet-based teleconferencing methods. The referring pathologists acquired the real-time video images from the biopsies using a light microscope equipped with a phototube adapter and a video camera. The consultant pathologists viewed the processed images on a video monitor at 800 x 600 resolution, using a standard microcomputer equipped with Netmeeting software, and directed the referring pathologist to move the slide under the microscopy and/or change image magnification. The validity of telepathology diagnoses was assessed with kappa coefficients. Consultations were completed in 5 to 15 minutes per case. Sound transmission was unreliable, and in approximately 25% of consultations the referring pathologist needed to "call back" to reestablish verbal communication. In all but 2 transbronchial biopsies there was agreement between the original diagnosis and the diagnosis by telepathology (kappa = 0.92). In 48 of 58 endomyocardial biopsies there was concordance between the 2 diagnoses (kappa = 0.692). Only 3 out of 10 of these discrepancies were clinically significant (kappa = 0.897). Internet-based teleconferencing techniques provide effective and relatively inexpensive tools for real time telepathology consultations. The technology is probably best suited for the study of small specimens from patients that require rapid diagnosis by a consultant.

The virtual blood film

The computer and the digital camera offer unprecedented possibilities for improving hematology education, research, and patient service. Peripheral blood smear images of exceptional quality can be acquired rapidly and conveniently from the peripheral blood smear with a modern, high-resolution digital camera and a quality microscope. Digital cameras use CCD or CMOS image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Because digital cameras do not use photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by e-mail, or other applications. Several excellent consumer digital still cameras are now available for less than $1000 that capture high-quality images comprised of more than three megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 8 x 10 in. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of peripheral blood smears. Because hematology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to develop large electronic hematology atlases; animated, audio-enhanced learning experiences; multidisciplinary Internet conferences; and other innovative applications. Digital images of single microscopic fields (single-frame images) are the most widely used in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare zoomable panoramas that encompass a large part of a microscope slide and closely stimulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Interactive, immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete later in this decade. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and obtain experimental data.

Automated complete slide digitization: a medium for simultaneous viewing by multiple pathologists

Developments in telepathology robotic systems have evolved the concept of a 'virtual microscope' handling 'digital slides'. Slide digitization is a method of archiving salient histological features in numerical (digital) form. The value and potential of this have begun to be recognized by several international centres. Automated complete slide digitization has application at all levels of clinical practice and will benefit undergraduate, postgraduate, and continuing education. Unfortunately, as the volume of potential data on a histological slide represents a significant problem in terms of digitization, storage, and subsequent manipulation, the reality of virtual microscopy to date has comprised limited views at inadequate resolution. This paper outlines a system refined in the authors' laboratory, which employs a combination of enhanced hardware, image capture, and processing techniques designed for telepathology. The system is able to scan an entire slide at high magnification and create a library of such slides that may exist on an internet server or be distributed on removable media (such as CD-ROM or DVD). A digital slide allows image data manipulation at a level not possible with conventional light microscopy. Combinations of multiple users, multiple magnifications, annotations, and addition of ancillary textual and visual data are now possible. This demonstrates that with increased sophistication, the applications of telepathology technology need not be confined to second opinion, but can be extended on a wider front.

Effect of image compression on telepathology. A randomized clinical trial

CONTEXT

For practitioners deploying store-and-forward telepathology systems, optimization methods such as image compression need to be studied.

OBJECTIVE

To determine if Joint Photographic Expert Group (JPG or JPEG) compression, a glossy image compression algorithm, negatively affects the accuracy of diagnosis in telepathology.

DESIGN

Double-blind, randomized, controlled trial.

SETTING

University-based pathology departments.

PARTICIPANTS

Resident and staff pathologists at the University of Illinois, Chicago, and University of Cincinnati, Cincinnati, Ohio.

INTERVENTION

Compression of raw images using the JPEG algorithm.

MAIN OUTCOME MEASURES

Image acceptability, accuracy of diagnosis, confidence level of pathologist, image quality.

RESULTS

There was no statistically significant difference in the diagnostic accuracy between noncompressed (bit map) and compressed (JPG) images. There were also no differences in the acceptability, confidence level, and perception of image quality. Additionally, rater experience did not significantly correlate with degree of accuracy.

CONCLUSIONS

For providers practicing telepathology, JPG image compression does not negatively affect the accuracy and confidence level of diagnosis. The acceptability and quality of images were also not affected.

Telepathology: a diagnostic tool for the millennium?

Many developments in science have their origins in science fiction and telepathology is no exception. The concept was first illustrated in 1924 in the magazine 'Radio News'. It was not until 1980, however, that the first working telepathology system was demonstrated. Although the system was shown to work, it required special hardware, dedicated software and special microwave transmission links to be installed. Little interest was shown worldwide because of the very high cost and the inability of many people to replicate such a system. Ten years later, the personal computer (PC) was able to provide more than adequate performance at low cost for both image display quality and speed, and the development of video technology had resulted in high quality images being produced by television cameras that were now easily affordable. Microscopes were also relatively cheaper. Thus, by 1993 or 1994, all the hardware necessary to produce a telepathology system was available at reasonable cost. Telepathology can now be used for remote primary diagnosis, remote referral to a specialist pathologist, remote teaching, remote presentation of post-mortem or microscopic findings, quality assurance image circulation and feedback, and consensus diagnosis for pathological review in clinical trials. There are two residual problems. The first concerns the speed of data transmission, commonly referred to as the bandwidth. The second is that the software provided by most of the manufacturers and suppliers of these systems is not entirely suitable to the task and the systems are not interoperable. It is clear that the approach of the manufacturers is at present unlikely to produce telepathology systems which pathologists feel comfortable in using. A somewhat different approach is illustrated by the accompanying article in this issue from the Berlin group, where a relatively simple Java-based applet and the Internet are used to allow single or multiple users to view slides on a robotic microscope. This could form the basis for a truly useful system, but still needs modification for some applications.

"Virtual microscopy" and the internet as telepathology consultation tools: diagnostic accuracy in evaluating melanocytic skin lesions

The Internet offers a widely available, inexpensive tool for telepathology consultations. It allows the transfer of image and text files through electronic mail (e-mail) or file transfer protocols (FTP), using a variety of microcomputer platforms. We studied the use of the Internet and "virtual microscopy" tools for the diagnosis of 35 skin biopsies, including a variety of benign and malignant melanocytic lesions. Digitized images from these lesions were obtained at 40x and 100x optical magnification, using a high resolution digital camera (Microlumina, Leaf Systems, Southborough, MA), a light microscope with a phototube adapter and a microcomputer with a Pentium 166 MHz microprocessor. Two to four images of each case were arranged on a "canvas" to represent the majority or an entire biopsy level, using Photoshop software (Adobe Systems Inc., San Jose, CA). The images were compressed using Joint Photographers Expert Group (JPEG) format. The images were then viewed on a computer video monitor in a manner that closely resembles light microscopy, including scrolling by using the "hand tool" of Photoshop and changing magnification digitally up to 4 times without visible image degradation. The image files, ranging in size from 700 kilobytes to 2.1 megabytes (average 1.6 megabytes) were attached to e-mail messages that contained clinical information, using standard Multipurpose Internet Mail Extension (MIME) protocols and sent through the Internet, for interpretation by a dermatopathologist. The consultant could open the images from the e-mail message, using Microsoft Outlook Express (Microsoft Corp., Redmond, WA) and Photoshop software, scroll them, change magnification and render a diagnosis in a manner that closely simulates light microscopy. One hundred percent concordance was obtained between the telepathology and traditional hematoxylin and eosin slide diagnoses. The Internet and relatively inexpensive "virtual microscopy" tools offer a novel technology for dermatopathology consultations. Potential applications of this technology to pathology and technical problems posed by the use of an open, widely distributed network to share sensitive medical information are discussed.