Biomedical subjects

Yukako Yagi

Publications and source records attributed to Yukako Yagi.

6 recordsLinked to original sources

PubMed2006

Primary histologic diagnosis using automated whole slide imaging: a validation study.

BACKGROUND: Only prototypes 5 years ago, high-speed, automated whole slide imaging (WSI) systems (also called digital slide systems, virtual microscopes or wide field imagers) are becoming increasingly capable and robust. Modern devices can capture a slide in 5 minutes at spatial sampling periods of less than 0.5 micron/pixel. The capacity to rapidly digitize large numbers of slides should eventually have a profound, positive impact on pathology. It is important, however, that pathologists validate these systems during development, not only to identify their limitations but to guide their evolution. METHODS: Three pathologists fully signed out 25 cases representing 31 parts. The laboratory information system was used to simulate real-world sign-out conditions including entering a full diagnostic field and comment (when appropriate) and ordering special stains and recuts. For each case, discrepancies between diagnoses were documented by committee and a "consensus" report was formed and then compared with the microscope-based, sign-out report from the clinical archive. RESULTS: In 17 of 25 cases there were no discrepancies between the individual study pathologist reports. In 8 of the remaining cases, there were 12 discrepancies, including 3 in which image quality could be at least partially implicated. When the WSI consensus diagnoses were compared with the original sign-out diagnoses, no significant discrepancies were found. Full text of the pathologist reports, the WSI consensus diagnoses, and the original sign-out diagnoses are available as an attachment to this publication. CONCLUSION: The results indicated that the image information contained in current whole slide images is sufficient for pathologists to make reliable diagnostic decisions and compose complex diagnostic reports. This is a very positive result; however, this does not mean that WSI is as good as a microscope. Virtually every slide had focal areas in which image quality (focus and dynamic range) was less than perfect. In some cases, there was evidence of over-compression and regions made "soft" by less than perfect focus. We expect systems will continue to get better, image quality and speed will continue to improve, but that further validation studies will be needed to guide development of this promising technology.

Journal Article↗

PubMed2006

Use of whole slide imaging in surgical pathology quality assurance: design and pilot validation studies.

By imaging large numbers of slides automatically at high resolution, modem automated whole slide imaging (WSI) systems have the potential to become useful tools in pathology practice. This article describes a pilot validation study for use of automated high-speed WSI systems for surgical pathology quality assurance (QA). This was a retrospective comparative study in which 24 full genitourinary cases (including 47 surgical parts and 391 slides) were independently reviewed with traditional microscopy and whole slide digital images. Approximately half the cases had neoplasia in the diagnostic line. At the end of the study, diagnostic discrepancies were evaluated by a pathology consensus committee. The study pathologists felt that the traditional and WSI methods were comparable for case review. They reported no difference in perceived case complexity or diagnostic confidence between the methods. There were 4 clinically insignificant discrepancies with the signed-out cases: 2 from glass slide and 2 with WSI review. Of the 2 discrepancies reported by the WSI method, the committee agreed with the reviewer once and the original report once. At the end of the study, the participants agreed that automated WSI is a viable potential modality for surgical pathology QA, especially in multifacility health systems that would like to establish interfacility QA. The participants felt that major issues limiting the implementation of WSI-based QA did not involve image acquisition or quality but rather image management issues such as the pathologist's interface, the hospital's network, and integration with the laboratory information system.

Humans↗

PubMed2005

Digital staining for multispectral images of pathological tissue specimens based on combined classification of spectral transmittance.

In this study, the digital transformation (digital staining) of the 16-band multispectral image of a hematoxylin and eosin (HE) stained pathological specimen to its Masson's trichrome (MT) stained counterpart is addressed. The digital staining procedure involves the classification of the various H&E-stained tissue components and then the transformation of their transmittance spectra to their equivalent MT-stained transmittance configurations. Combination of transmittance classifiers were designed to classify the various tissue components found in the multispectral images of an HE-stained specimen, e.g. nucleus, cytoplasm, red blood cell (RBC), fibrosis, etc.; while pseudo-inverse method was used to obtain the transformation matrices that would translate the transmittance spectra of the classified HE-stained multispectral pixels to their MT-stained configurations. To generate the digitally stained image, weighting factors, which were based on the classifiers beliefs, were introduced to the generated transformation matrices. Initial results of our experiments on liver specimens show the viability of multispectral imaging (MSI) to implement a digital staining framework in the pathological context.

Diagnosis, Computer-Assisted↗

PubMed2005

Digital imaging in pathology: the case for standardization.

The process of digital imaging in microscopy is a series of operations, each contributing to the quality of the final image that is displayed on the computer monitor. The operations include sample preparation and staining by histology, optical image formation by the microscope, digital image sampling by the camera sensor, postprocessing and compression, transmission across the network and display on the monitor. There is an extensive literature about digital imaging and each step of the process is fairly well understood. However, the complete process is very hard to standardize or even to understand fully. The important concepts for pathology imaging standards are: (1) systems should be able to share image files, (2) the standards should allow the transmission of information on baseline colours and recommended display parameters, (3) the images should be useful to the pathologist, not necessarily better or worse than direct examination of a slide under the microscope, (4) a mechanism to evaluate image quality objectively should be present, (5) a mechanism to adjust and correct the minor errors of tissue processing should be developed, (6) a public organization should support pathologists in the development of standards.

Image Interpretation, Computer-Assisted↗

PubMed2004

Webcasting pathology department conferences in a geographically distributed medical center.

As academic pathology departments have become increasingly based in large, regional medical systems spread across hundreds of square miles, new methods are needed to tie these increasingly distributed departments together as integrated units. An important part of that integration is the ability to share academic and teaching conferences across long distances. In this article we present an effective, low-cost webcasting system that has evolved at the University of Pittsburgh Medical Center Department of Pathology over the past several years based on inexpensive, widely available software. To date, the system has broadcast and archived more than 400 conferences and currently serves approximately 80 to 100 requests each week. Important factors in the success of the program include the creation of a faculty steering committee to control resources and manage growth, the availability of informatics faculty and support for technical staff, and the decision to operate the service as part of the core information technology infrastructure of the department. Webcasting will likely become an even more important academic and operational tool in the future as more of the department's conferences, seminars, and even working meetings are communicated through the webcasting infrastructure.

Academic Medical Centers↗

PubMed2002

IP telephony--new horizon for telemedicine and e-health.

Internet Protocol (IP) based networks are increasingly being used as alternatives to the traditional circuit-switched networks for carrying voice traffic. IP telephony is taking a firm hold in the world telecommunication market for a wide range of applications including telemedicine. The merits of IP telephony for telemedicine lie in cost-savings and new applications and functionalities it may render. In this paper, we try to discuss and analyze the implications of IP telephony on the evolution and deployment of telemedicine and e-health.

Computer Communication Networks↗