Advancing Practice, Instruction, and Innovation Through Informatics (APIII 2003): Scientific Session and E-Poster Abstracts

Archives of Pathology & Laboratory Medicine, Oct 2004 by Becich, Michael J, Crowley, Rebecca

Scientific (http://apiii.upmc.edu/abstracts/scientific.html) and e-poster (http:// apiii.upmc.edu/abstracts/poster.html) sessions were conducted at the eighth national conference on Advancing Practice, Instruction, and Innovation through Informatics (APIII 2003) on October 8-10, 2003, in Pittsburgh, Pa. The course directors were Michael J. Becich, MD, PhD, professor of Pathology and Information Sciences & Telecommunications, director of the Center for Pathology Informatics, and director of Benedum Oncology Informatics Center at the University of Pittsburgh, Pittsburgh, Pa; and Rebecca Crowley, MD, assistant professor, Pathology and Intelligent Systems, University of Pittsburgh, School of Medicine.

SCIENTIFIC SESSION ABSTRACTS

Comparison of Stain Quantification for Histological Specimens Using Spectrometer and Multi-Band Image Data

Othman Abdul-Karim' (abdulkarimoa@upmc.edu); Tokiya Abe, MS2; Masahiro Yamaguchi-·1; Yukako Yagi.1 'Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pa; 2Tokyo Institute of Technology, Imaging Science & Engineering Laboratory, Tokyo, Japan; Telecommunication Advancement Organization, Akasaka Natural Vision Research Center, Tokyo, Japan.

Context: Accurate analysis of histopathologic tissue samples is important in pathologic diagnosis. This experiment is part of a multispectral research project for a decision support system. Sample tissue is normally observed under a bright-field microscope after the tissue has been stained. Normally in histologie stains, color signals the biochemical makeup of various tissue regions. One of the most popular staining methods is hematoxylin-eosin (H&E). This method selectively stains the nucleus and cytoplasm. In this study, the amount of stain will be calculated in different small regions in a tissue slide using 2 methods. In the first method the amount of stain will be estimated using only spectrometer data, and in the second method it will be estimated from 16-band image data.

Technology: To calculate stain amount, estimation of transmittance spectra is needed. Normally a spectral measurement device called a spectrometer is used with a microscope to measure transmittance spectra. However, such a device is expensive and requires a highly experienced operator. It is preferred to estimate transmittance spectra without using a spectrometer. The transmittance spectra will be estimated from 16-band image data. Estimation of transmittance spectra is important in areas such as tissue stain standardization in digital color images, stain detection in tissue color images, and also in tissue image segmentation.

Design: The purpose of this study is to compare stain amount obtained using spectrometer data to stain amount estimated using a multiband imaging system. In the first method, the transmittance spectra at selected small sample regions in the stained tissue are measured using a microscope spectrometer, brightfield microscope, and xyz stage, and the H&E amounts are estimated in the sample regions using the Beer-Lambert Law. In the second method, an imaging system is used to take multiband images using a bright-field microscope, 1 charge coupled device (CCD; 2K × 2K) digital camera, and 16 filters. The transmittance spectrum in each pixel in the image is estimated first using camera sensitivity data, the 16-filter transmittance data, and illumination spectra. The H&E stain amounts are estimated using the Beer-Lambert Law and a priori information about H&E spectral transmittance data.

Results: Using a spectrometer, the transmittance spectrum is measured in a number of small regions in a stained tissue slide. Using the Beer-Lambert Law, the amount of H&E stain is estimated. The transmittance spectrum is calculated in all pixels in the image, using method 2. The average value of the transmittance spectra in each region used in method 1 is calculated, and the root mean square error between the transmittance spectra measured in methods 1 and 2 is calculated. The amounts of H&E stain estimated from method 1 will be compared with the average value of stain amounts estimated using method 2 for each region.

Conclusions: This study compares 2 methods to estimate transmittance spectra and stain amounts in a stained tissue slide. Experiments conducted show normalized root mean square error for transmittance spectra within 6%. Stain amounts estimated using both measurement methods are in close agreement.

Standardization of Stain Condition

Tokiya Abe' (tokiya@isl.titech.ac.jp); Nagaaki Ohyama2; Masahiro Yamaguchi1; Yuri Murakami2; Yukako Yagi.3 'Tokyo Institute of Technology, Imaging Science & Engineering Laboratory, Tokyo, Japan; 2Tokyo Institute of Technology, Frontier Collaborative Research Center, Tokyo, Japan; 'Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pa.

Context: Stain conditions are not always constant, as the staining technique strongly depends on hospitals or an individual histotechnologist. Trials for reducing the variety of stain variation by standardizing staining procedures have been tried, but they have not yielded good results because of the complexity of the staining procedure. To develop a decision support system, standardization of the stain conditions of tissue samples is required. First, we worked to standardize the hematoxylin-eosin stain. For this purpose, we used multispectral imaging techniques.