Masayuki Nambu

E-Healthcare at an Experimental Welfare Techno House in Japan

An automated monitoring system for home health care has been designed for an experimental house in Japan called the Welfare Techno House (WTH). Automated electrocardiogram (ECG) measurements can be taken while in bed, in the bathtub, and on the toilet, without the subject’s awareness, and without using body surface electrodes. In order to evaluate this automated health monitoring system, overnight measurements were performed to monitor health status during the daily lives of both young and elderly subjects.

An algorithm for the automatic detection of health conditions

In this article, an algorithm for a health diagnosis system for the elderly that uses image processing was developed. This algorithm reconstructs monochrome images from data of the time a subject watches TV and calculates the index for diagnosis of the subjects health condition from the entropy of the image. When this algorithm was applied to the data obtained for seven months, the result almost corresponded to the health condition of the subject. It is assumed that this method can be used not only for diagnosis of a physical condition but also for diagnosis of a mental condition. As a result of the evaluation, this algorithm is considered to be effective according to the subject. In addition, this method was economical because the algorithm needed only simple data acquired from simple sensors. In the future, an automatic diagnosis will be available using this algorithm. Finally, total medical expenses will be reduced if this system is practical.

Low-cost, email-based system for self blood pressure monitoring at home.

We have developed a low-cost monitoring system, which allows subjects to send blood pressure (BP) data obtained at home to health-care professionals by email. The system consists of a wrist BP monitor and a personal computer (PC) with an Internet connection. The wrist BP monitor includes an advanced positioning sensor to verify that the wrist is placed properly at heart level. Subjects at home can self-measure their BP every day, automatically transfer the BP data to their PC each week, and then send a comma-separated values (CSV) file to their health-care professional by email. In a feasibility study, 10 subjects used the system for a mean period of 207 days (SD 149). The mean percent achievement of measurement in the 10 subjects was 84% (SD 12). There was a seasonal variation in systolic and diastolic BP, which was inversely correlated with temperature. Eight of the 10 subjects evaluated the system favourably. The results of the present study demonstrate the feasibility of our email-based system for self-monitoring of blood pressure. Its low cost means that it may have widespread application in future home telecare studies.

Unconstrained monitoring of prevention of wandering the elderly

Wandering demented patients are in danger of falling and injuring themselves without a caregivers support. In this study, we developed an unconstrained monitoring system that notifies wandering in the elderly to their caregiver. The system consists of a step sensor that detects the contact on the floor, an interface for transmitting data to the caregivers and floor lighting. Foot switch was installed beside a subjects bed. When the wandering is detected caregiver is notified it by phone calling via a personal handy-phone system (PHS). The developed system was tested for three subjects and successfully detected the wandering of subjects.

A Method for 3D Measurement with High Resolution Using Ultrasound Spherical Waves

Many methods for 3D measurement using ultrasound spherical waves with many ultrasound receivers have been proposed to date for use as sonars applied to fish-finders and underground locators. These methods, however, generated elliptically symmetric artifacts so that even a simply shaped object was revealed as distorted elliptic planes in 3D (lines in 2D) which made it difficult to recognize its shape. This paper describes a newly developed 3D measurement method using ultrasound spherical waves with an ultrasound ring-array probe. Our new method does not weight points aligned on an elliptic plane with the same value. This method is based not on a simple expansion method but on an optimization method. To evaluate the system and to compare it with the previous algorithms, a computer simulation assuming several point reflectors was performed. The results indicated that point reflectors were represented not in the elliptic planes but as points placed the assuming location. This method is especially useful for intravascular ultrasound frontal viewing.

Body Surface Mounted Biomedical Monitoring System using Bluetooth

Continuous monitoring in daily life is important for the health condition control of the elderly. However, portable or wearable devices need to carry by user on their own will. On the other hand, implantation sensors are not adoptable, because of generic users dislike to insert the any object in the body for monitoring. Therefore, another monitoring system of the health condition to carry it easily is necessary. In addition, ID system is necessary even if the subject live with few families. Furthermore, every measurement system should be wireless system, because not to obstruct the daily life of the user. In this paper, we propose the monitoring system, which is mounted on the body surface. This system will not obstruct the action or behavior of user in daily life, because this system attached the body surface on the back of the user. In addition, this system has wireless communication system, using Bluetooth, and acquired data transfer to the outside of the house via the Internet.

WWW based ECG transfer for home care using JAVA script

A home care system using information technology is important role in the aged society, because the number of the caregiver will decrease and assistive device using information technology and robotics is required in the near future. Thus, several home care systems has been developed and the part of them are marketed. Because the special hardware or software is necessary, the conventional systems are expensive for widely use. Therefore, we have proposed the home care system using WWW technology. In this paper, we describe the ECG transfer system using JAVA script. In this system, special plugins such as JAVA virtual machine are unnecessary to browse the ECG excluding WWW browser. Therefore, PDA or the mobile phone is available for tele-diagnosis.

Smart sensing of cardiovascular physiological information from soles without direct skin contact

This study proposes the development of a smart sensing measurement system using a mat-type sensor in order to obtain sole-electrocardiogram data from soles and toe-photoplethysmogram data from toes. In addition, the proposed measurement system can calculate pulse wave velocity from sole-ECG and toe-PPG. The subjective experiments revealed that the developed system can measure these parameters even when socks are being worn. Moreover, simultaneous measurements of systolic blood pressure and PWV determined by the developed system indicate a strong correlation was found between SBP and PWV. Therefore, this system can detect cardiovascular diseases or symptoms of common diseases and suggests the possibility to estimate the temporal changes in SBP without required compression using cuffs.

Applying NISHIJIN historical textile technique for e-Textile

The e-Textile is the key technology for continuous ambient health monitoring to increase quality of life of patients with chronic diseases. The authors introduce techniques of Japanese historical textile, NISHIJIN, which illustrate almost any pattern from one continuous yarn within the machine weaving process, which is suitable for mixed flow production. Thus, NISHIJIN is suitable for e-Textile production, which requires rapid prototyping and mass production of very complicated patterns. The authors prototyped and evaluated a few vests to take twelve-lead electrocardiogram. The result tells that the prototypes obtains electrocardiogram, which is good enough for diagnosis.

A practical application of pressure-sensitive film for preventing pressure sores

To prevent pressure sores, the authors proposed a practical application of pressure-sensitive film. The film was attached directly to the hip of a wheelchair user to evaluate the concentration of weight at bony prominences. The results of the pressure distribution for a normal wheelchair seat were compared with those for a cushion, using simple image processing. The red color density of the film was digitized to an image at a resolution of 50 dpi. The image was processed to a mosaic image to eliminate high-frequency noise. A histogram of intensity, obtained from the mosaic image, was used to evaluate the concentrated weight. The maximum value, average and standard deviation represented the histogram. The result demonstrates clearly that the histogram indicates differences of pressure concentration and distribution on the wheelchair with and without the cushion. This method may be effective for preventing pressure sores.