Person: Yagi, Yukako
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Yagi
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Yukako
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Yagi, Yukako
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Publication Reflectance Confocal Microscopy for the Diagnosis of Eosinophilic Esophagitis: a Pilot Study Conducted on Biopsy Specimens(Elsevier BV, 2011) Yoo, Hongki; Kang, Dongkyun; Katz, Aubrey; Lauwers, Gregory Y.; Nishioka, Norman; Yagi, Yukako; Tanpowpong, Pornthep; Namati, Jacqueline; Bouma, Brett; Tearney, GuillermoBackground: Diagnosis of eosinophilic esophagitis (EoE) currently requires endoscopic biopsy and histopathologic analysis of the biopsy specimens to count intraepithelial eosinophils. Reflectance confocal microscopy (RCM) is an endomicroscopy technology that is capable of obtaining high-resolution, optically sectioned images of esophageal mucosa without the administration of exogenous contrast. Objective: In this study, we investigated the capability of a high-speed form of RCM, termed spectrally encoded confocal microscopy (SECM), to count intraepithelial esophageal eosinophils and characterize other microscopic findings of EoE. Design: A total of 43 biopsy samples from 35 pediatric patients and 8 biopsy samples from 8 adult patients undergoing EGD for EoE were imaged by SECM immediately after their removal and then processed for routine histopathology. Two SECM readers, trained on adult cases, prospectively counted intraepithelial eosinophils and detected the presence of abscess, degranulation, and basal cell hyperplasia on SECM images from the pediatric patients. A pathologist blinded to the SECM data analyzed the same from corresponding slides. Setting: The Gastrointestinal Unit, Massachusetts General Hospital. Results: Eosinophils by SECM demonstrated a higher reflectance than the surrounding cells and other inflammatory cells. There was good correlation between SECM and histology maximum eosinophil counts/high-power field (R = 0.76, P < .0001). Intra- and interobserver correlations for SECM counts were very good (R = 0.93 and R = 0.92, respectively; P < .0001). For the commonly used eosinophil count cutoff of 15 per high-power field, the sensitivity and specificity of SECM for EoE were 100%. The sensitivity and specificity for abscess, degranulation, and basal cell hyperplasia were 100% and 82%, 91% and 60%, and 94% and 80%, respectively. Intra- and interobserver agreements for these microscopic features of EoE were very good (κ = 0.9/0.9, 0.84/1.0, 0.91/0.81, respectively). Limitation: Ex vivo study. Conclusions: This study demonstrates that RCM can be used to accurately count intraepithelial eosinophils and identify other microscopic abnormalities associated with EoE on freshly excised biopsy samples. These findings suggest that RCM may be developed into a tool for assessing eosinophilic infiltration in the esophagus in vivo.Publication Balancing Image Quality and Compression Factor for Special Stains Whole Slide Images(IOS Press, 2012) Sharma, Anurag; Bautista, Pinky Abarca; Yagi, YukakoThe objective is to find a practical balance between quality and performance for daily high volume whole slide imaging. We evaluated whole slide images created by various scanners at different compression factors to determine the best suitable quality factor (QF) needed for pathological images of special stains. Method: We scanned two sets of eight special stains slides each at 0.50 μm/pixel resolution in Hamamatsu scanner at six and five QF levels respectively to generate 72 images which were observed at a calibrated monitor by imaging specialists, a histo-technician, and a pathologist to find the most suitable QF level for special stains in digital slides. Results: Most special stains images were acceptable at QF 30 except for the stain Reticulin where the lowest acceptable QF was 50. The compression of images from QF 90 to QF 50 reduced the size of the images by 62.73%. Conclusion: 0.50 μm/pixel images at QF 50 or above were found suitable 12 special stain.Publication A Role of Three-Dimensional (3D)-Reconstruction in the Classification of Lung Adenocarcinoma(IOS Press, 2012) Onozato, Maristela Lika; Klepeis, Veronica; Yagi, Yukako; Mino-Kenudson, MariBackground:: Three-dimensional (3D)-reconstruction from paraffin embedded sections has been considered laborious and time-consuming. However, the high-resolution images of large object areas and different fields of view obtained by 3D-reconstruction make one wonder whether it can add a new insight into lung adenocarcinoma, the most frequent histology type of lung cancer characterized by its morphological heterogeneity. Objective:: In this work, we tested whether an automated tissue sectioning machine and slide scanning system could generate precise 3D-reconstruction of microanatomy of the lung and help us better understand and define histologic subtypes of lung adenocarcinoma. Methods:: Four formalin-fixed human lung adenocarcinoma resections were studied. Paraffin embedded tissues were sectioned with Kurabo-Automated tissue sectioning machine and serial sections were automatically stained and scanned with a Whole Slide Imaging system. The resulting stacks of images were 3D reconstructed by Pannoramic Viewer software. Results:: Two of the four specimens contained islands of tumor cells detached in alveolar spaces that had not been described in any of the existing adenocarcinoma classifications. 3D-reconstruction revealed the details of spatial distribution and structural interaction of the tumor that could hardly be observed by 2D light microscopy studies. The islands of tumor cells extended into a deeper aspect of the tissue, and were interconnected with each other and with the main tumor with a solid pattern that was surrounded by the islands. The finding raises the question whether the islands of tumor cells should be classified into a solid pattern in the current classification. Conclusion:: The combination of new technologies enabled us to build an effective 3D-reconstruction of resected lung adenocarcinomas. 3D-reconstruction may help us refine the classification of lung adenocarcinoma by adding detailed spatial/structural information to 2D light microscopy evaluation.Publication Multispectral Enhancement Method to Increase the Visual Differences of Tissue Structures in Stained Histopathology Images(IOS Press, 2012) Bautista, Pinky Abarca; Yagi, YukakoIn this paper we proposed a multispectral enhancement scheme in which the spectral colors of the stained tissue-structure of interest and its background can be independently modified by the user to further improve their visualization and color discrimination. The colors of the background objects are modified by transforming their N-band spectra through an NxN transformation matrix, which is derived by mapping the representative samples of their original spectra to the spectra of their target colors using least mean square method. On the other hand, the color of the tissue structure of interest is modified by modulating the transformed spectra with the sum of the pixel’s spectral residual-errors at specific bands weighted through an NxN weighting matrix; the spectral error is derived by taking the difference between the pixel’s original spectrum and its reconstructed spectrum using the first M dominant principal component vectors in principal component analysis. Promising results were obtained on the visualization of the collagen fiber and the non-collagen tissue structures, e.g., nuclei, cytoplasm and red blood cells (RBC), in a hematoxylin and eosin (H&E) stained image.Publication Multispectral Enhancement towards Digital Staining(IOS Press, 2012) Bautista, Pinky Abarca; Yagi, YukakoBackground:: Digital staining can be considered as a special form of image enhancement wherein the concern is not only to increase the contrast between the background objects and objects of interest, but to also impart the colors that mark the objects’ unique reactions to a specific stain. In this paper, we extended the previously proposed multispectral enhancement methods such that the colors of the background pixels can also be changed. Methods:: In the previous multispectral enhancement methods a shifting factor is provided to the original spectrum. To implement digital staining, a spectral transformation process is introduced prior to spectral shifting. Results:: The enhancement method is applied to multispectral images of H&E stained liver tissue. The resulting digitally stained images show good correlation with the serial-section images of the tissue which are physically stained with Masson's trichrome. Conclusion:: We have presented a multispectral enhancement method that can be adjusted to produce digitally stained-images. The current experimental results show the viability of the method. However, to achieve robust enhancement performance issues that arise from variations in staining conditions has to be addressed as well. This would be part of our future work.Publication An Ultra-High Speed Whole Slide Image Viewing System(IOS Press, 2012) Yagi, Yukako; Yoshioka, Shigeatsu; Kyusojin, Hiroshi; Onozato, Maristela Lika; Mizutani, Yoichi; Osato, Kiyoshi; Yada, Hiroaki; Mark, Eugene; Frosch, Matthew; Louis, DavidBackground:: One of the goals for a Whole Slide Imaging (WSI) system is implementation in the clinical practice of pathology. One of the unresolved problems in accomplishing this goal is the speed of the entire process, i.e., from viewing the slides through making the final diagnosis. Most users are not satisfied with the correct viewing speeds of available systems. We have evaluated a new WSI viewing station and tool that focuses on speed. Method: A prototype WSI viewer based on PlayStation®3 with wireless controllers was evaluated at the Department of Pathology at MGH for the following reasons: 1. For the simulation of signing-out cases; 2. Enabling discussion at a consensus conference; and 3. Use at slide seminars during a Continuing Medical Education course. Results:: Pathologists were being able to use the system comfortably after 0–15 min training. There were no complaints regarding speed. Most pathologists were satisfied with the functionality, usability and speed of the system. The most difficult situation was simulating diagnostic sign-out. Conclusion:: The preliminary results of adapting the Sony PlayStation®3 (PS3®) as an ultra-high speed WSI viewing system were promising. The achieved speed is consistent with what would be needed to use WSI in daily practice.Publication Consistency and Standardization of Color in Medical Imaging: a Consensus Report(Springer US, 2014) Badano, Aldo; Revie, Craig; Casertano, Andrew; Cheng, Wei-Chung; Green, Phil; Kimpe, Tom; Krupinski, Elizabeth; Sisson, Christye; Skrøvseth, Stein; Treanor, Darren; Boynton, Paul; Clunie, David; Flynn, Michael J.; Heki, Tatsuo; Hewitt, Stephen; Homma, Hiroyuki; Masia, Andy; Matsui, Takashi; Nagy, Balázs; Nishibori, Masahiro; Penczek, John; Schopf, Thomas; Yagi, Yukako; Yokoi, HidetoThis article summarizes the consensus reached at the Summit on Color in Medical Imaging held at the Food and Drug Administration (FDA) on May 8–9, 2013, co-sponsored by the FDA and ICC (International Color Consortium). The purpose of the meeting was to gather information on how color is currently handled by medical imaging systems to identify areas where there is a need for improvement, to define objective requirements, and to facilitate consensus development of best practices. Participants were asked to identify areas of concern and unmet needs. This summary documents the topics that were discussed at the meeting and recommendations that were made by the participants. Key areas identified where improvements in color would provide immediate tangible benefits were those of digital microscopy, telemedicine, medical photography (particularly ophthalmic and dental photography), and display calibration. Work in these and other related areas has been started within several professional groups, including the creation of the ICC Medical Imaging Working Group.Publication Mitotic Figure Recognition: Agreement among Pathologists and Computerized Detector(IOS Press, 2012) Malon, Christopher; Brachtel, Elena; Cosatto, Eric; Graf, Hans Peter; Kurata, Atsushi; Kuroda, Masahiko; Meyer, John S.; Saito, Akira; Wu, Shulin; Yagi, YukakoDespite the prognostic importance of mitotic count as one of the components of the Bloom – Richardson grade [3], several studies ([2, 9, 10]) have found that pathologists’ agreement on the mitotic grade is fairly modest. Collecting a set of more than 4,200 candidate mitotic figures, we evaluate pathologists' agreement on individual figures, and train a computerized system for mitosis detection, comparing its performance to the classifications of three pathologists. The system’s and the pathologists’ classifications are based on evaluation of digital micrographs of hematoxylin and eosin stained breast tissue. On figures where the majority of pathologists agree on a classification, we compare the performance of the trained system to that of the individual pathologists. We find that the level of agreement of the pathologists ranges from slight to moderate, with strong biases, and that the system performs competitively in rating the ground truth set. This study is a step towards automatic mitosis count to accelerate a pathologist's work and improve reproducibility.Publication Whole Slide Imaging Based Digital Pathology Network between Pakistan and USA(Hindawi Publishing Corporation, 2014) Absar, Syeda Fatima; Tahir, Mohammad; Yagi, Yukako; Wilbur, DavidPublication Connection and Deformation of Pathological Images via a Macro Image for Comparing Different Modality Images of Brain Tumor(Hindawi Publishing Corporation, 2014) Ohnishi, Takashi; Tanaka, Takuya; Nakamura, Yuka; Hashimoto, Noriaki; Haneishi, Hideaki; Taylor, Jennie; Snuderl, Matija; Yagi, Yukako