It is very important to evaluate fibroglandular breast tissue to define the degree of risk of the lesions being obscured by normal breast tissue. A classification criterion of mammographic parenchymal patterns was defined by Wolfe in 1976; however, it is not always applied to Asian women's breasts because their breast images tend to be comparatively dense. We developed an automated classification method for Asian women's mammograms. The radiologists confirmed the effectiveness of this classification method by classification experiments. The mammograms are divided into three regions by a local thresholding technique and classified into four categories based on the rate of each of three regions. The method was evaluated on 99 clinical mammograms classified by physicians. The results showed that the agreement rate between physicians and computer was approximately 90%.

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Various vital sensors have been developed for patient monitoring. These sensors restrict patients physically or mentally since either electrodes or probes must be mounted onto a patient's body and then connected to a measuring instrument using a lead wire. In this study, a biomedical-signal detection system capable of being used without subject awareness on the basis of terrestrial magnetism was developed for home use and remote care. When a subject lies on a bed mattress that is situated on a magnetic sheet, the system detects the change in magnetic field related to respiration and heart beat. We have also developed an on-line system that can separate respiration and heart beat components from the detected signal.

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The purpose of this paper is to propose a detection scheme for masses existing around thick mammary gland regions. The scheme includes a template-matching technique with four reference patterns, which are partial images extracted from a Gaussian distribution, and the feature values determined by concentrating feature and density gradient. The new algorithm consists of 11 steps: (i) image digitization, (ii) extraction of breast region, (iii) reduction of image matrix, (iv) dynamic-range compression, (v) density gradient calculation, (vi) extraction of pectralis muscle region, (vii) overall detection, (viii) elimination of false positives (1), (ix) regional detection, (x) elimination of false positives (2) and (xi) indication of detected masses. Although stage (ix) made it possible to detect the masses existing around thick mammary gland regions, the number of false positives on this region increased. Stage (x) was added for the elimination of new false positives that were detected by stage (ix). A total of 2, 008 digitized mammograms was used for the performance study. As a result, our new scheme identified 95% of the true masses with 2.4 false positives per image. It was possible to detect 43 of 52 masses that were not detected by our previous method. These results indicate that this proposed method is effective, although the process for elimination of false positives should be improved.

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The preparation of tissue sections for light microscopy is absolutely necessary in pathology. However, this process is still mainly performed manually. The preparation of many samples from a large number of specimens requires meticulous skills. In addition, it is very difficult to maintain constant accuracy in the procedure. To solve these problems, we propose a new test machine for automatic sample preparation that is conceptually based on attaching pressure-sensitive adhesive tape to the surface of the paraffin block followed by sectioning. This whole process can be repeated automatically. The sectioning operation is performed by a newly developed high-precision automatic microtome. Using the proposed method, sections can be taken out on the tape continuously. The entire system is composed of the following four units: The first unit is a tape feeding mechanism, the second attaches the tape on the surface of the specimen, the third performs the sectioning operation, and the fourth consists of a mechanism that winds up the tape to which the sections are attached. The developed apparatus successfully showed its capability to produce constant sections of 2μm or more in thickness. Moreover, the time required to make a section is 15sec As the conditions of examination at that time, the pulling angle was set to 30 degrees and 20mm/s at the cut speed. Pressure-sensitive adhesive elements used for the tape and the material of the tape have been improved. On the staining of the tape-mounted sections, the dissolution of the adhesives distorted the sections during xylene insuccation, and it eventually fell off. Improvements in the chemical resistance of both adhesives and tapes to solvent against decrease in transparency after hematoxylin and eosin (HE) staining were performed. As a result, the same quality as the conventional manual method after sealing with object glass could be obtained.

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The self-monitoring of blood glucose level (BGL) is a critical part of managing diabetes. However, present procedures for obtaining such information are invasive, painful, and provide only periodic measurements. Development of a painless approach would represent a significant improvement in the quality of life (QOL) for people with diabetes. The purpose of this research is to realize a portable noninvasive blood glucose measuring system using saliva. We developed three devices which constitute a noninvasive blood glucose measuring system. A new saliva collecting device, which has a simple structure, is proposed and it is produced experimentally. A stabilized quantity, 9μl of whole saliva, is collected using this device. Next, a testing tape which is used for measuring saliva glucose levels (SGL) was manufactured. Finally, a portable optical measuring system was manufactured to measure the change of absorbance of the testing tape. The measurement accuracy of the testing tape and optical measuring system satisfied requirement specifications of 0.5mg/dl. The accuracy of the blood glucose measuring system was evaluated using Error Grid Analysis. As a result, it is possible to obtain significant information to judge the disease state using this system, not only for normal subjects but diabetic subjects as well. The present study demonstrated that the noninvasive blood glucose measuring system using SGL can be used as an indicator of BGL.

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As a basis to develop a human interface for communication aids for the handicapped, we conducted a study on the behavior of P300 components for selecting one of the words presented on a monitor screen in a random sequence. The number of words displayed was varied (i. e., 2, 3, 5, 10 and 20), and five different conditions were tested. The P300 components were extracted from the target responses by means of the following methods: 1) Band-pass filtering of central frequency of 3Hz. 2) 30 times averaging. 3) Subtraction of the ERP response components common to both target and non-target stimuli. 4) Cutting out the P300 using the time-window of the trapezoidal form. Results show that the P300 peak amplitudes in the averaged responses were usually larger with the 20-word display than with the 2-word display, and the P300 peak latencies were longer with the 20-word display than with the 2-word display. The 5-word display, however, proved to be best for obtaining the right selection.

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