Mobihealth 2012 Invited Articles
Thursday, November 22, 2012: Invited session "Implants" (10.30 - 11.45)
- **Endocom and Cyclope – two smart biomedical sensors for cardio-vascular surgery and gastro-enterology**, Prof. Patrick Garda (Univ. Paris VI, France)
Recent progresses in microelectronics, micro electro mechanical systems (MEMS) and n wireless communications have opened new perspectives for biomedical smart sensors, particularly those that are implanted. In this paper, we present the results of two recent projects, ENDOCOM and CYCLOPE, that were led by teams from the LIP6 and ETIS laboratories.. Firstly, an abdominal aortic aneurysm (AAA) is a dilation of the aorta at the abdominal level. The rupture of an AAA is a life threatening complication with an 80% mortality rate. Covered stents are used to prevent suc an event Although these devices keep improving, the failure rate of this endovascular treatment is due to persisting pressure in the excluded aneurysmal sac. Since 2005, several integrated sensors were designed for the follow-up of the AAA treated by a stent. Solutions are based on the use of a single sensor. Thrombus in the excluded AAA can modify the field of pressure when leaks appear, therefore a network of sensors should be used. We present in this first part of this talk, the ENDOCOM project that aims to design an implantable pressure sensor that can be used in a network configuration. To validate the new devices, we developed a framework composed of in vitro experiments and in vivo tests on large animal models. Numerical modeling was investigated from the experimental data to determine the optimal position of the sensor. Some results of those different studies are given to demonstrater the feasibility of the proposed sensor for the follow-up of AAA. Secondly, the colorectal cancer is the first cause of death by cancer in developed regions, with an incidence in 2008 of 728.550 cases from which 43% resulting in death. Globally, it is the third cause with incidence of 1.235.108 cases and 49% of them resulting in death (after lung, 1.608,055 incidences, and breast, 1.384.155, cancers). Considering these statistics, any effort to decrease the incidence, would reduce the impact of one of the main causes of death in the world. Currently, the “Gold standard” examination leading to the diagnosis of colorectal cancer is the colonoscopy. Using a videoendoscope, the physician can observe and take videos of the entire gut and detect suspicious tissular structures like polyps which could degenerate into a cancer. However, the wireless capsule endoscopy represents an alternative which make it possible to analyze some diseases in post- examination. Moreover, the gastroenterologist could have a direct diagnosis if the video capsule integrated some vision algorithms. To increase the autonomy of video capsules it would be possible to transmit diagnosis results only, instead of transmitting all the acquired images. This second part of the talk focuses on the CYCLOPE project that is an embedded active vision system able to give in real time a diagnosis based both on the 3D and texture data. The challenge is to realize this integrated sensor with constraints on size, consumption and processing which are inherent limitations of a video capsule. We present the hardware and software development of a wireless multispectral vision sensor which allows to give a pre-diagnosis of polyps based both on the classification of the 3D reconstruction of the polyps by SVM and the classification of the texture by boosting methods. An FPGA-based prototype was designed to achieve a proof of concept. Experiments in laboratory, in vitro and in vivo on a pig were performed to estimate the performances of the 3D vision system. A roadmap towards the integration of the system is given.
- **An analog front-end and ADC integrated circuit for implantable force and position measurements in joint prosthesis**, Dr. Steve Tanner (EPFL, Switzerland)
The paper presents an analogue front-end and ADC integrated circuit for processing signals of sensors implanted into joint prosthesis. The circuit is designed to be operated with Wheatstone bridge sensors, such as strain gauges, pressure, Hall Effect, magneto-resistive sensors, etc. It performs sensor supply multiplexing, sensor signal amplification with chopper modulation, offset compensation and 14-bit analog to digital conversion in a single chip. It can operate simultaneously up to eight sensors at an overall bandwidth of 8 kHz, and can be directly interfaced to a remotely powered RFID system in order to constitute a complete multi-sensor, low-power, small size and externally powered micro-system. Integrated into a 180 nm CMOS process, it measures 5 mm2, is supplied with 1.8 Volt and consumes 1.8 mW.
- **Improving Power Efficiency in WBAN Communication Using Wake Up Methods**, Dr. Stevan Marinkovic (ABB, Switzerland)
Power efficient communication in a Wireless Body Area Net- work (WBAN) is critical for successful system deployment. Stringent constraints of size and weight of sensors significantly limit available sen- sor power, particularly in the case of implantable sensors. This paper discusses and analyses methods that could be used to improve power efficiency of implantable WBAN systems, with focus on the Wake Up Radio (WUR), which allows power efficient listening of wireless channel. The paper presents analysis of existing hardware and design trade offs in WUR implementation.
Friday November 23, 2012: Invited paper (15.45 - 16.30)
- **Computerization of the Medical Consult for Children under Five Years of Age in Rural Areas of Burkina Faso**, Guillaume Deflaux**, Resource Person on Information Systems, Terre des hommes Foundation
The Integrated Management of Childhood Illness (IMCI) is a diagnostic method and strategy developed by the World Health Organization (WHO) aiming to reduce the morbidity and mortality of children under 5 years of age. Adopted by Burkina Faso, its implementation in rural areas of the country is difficult due to an insufficient number of trained health workers and because difficult working conditions increase the lack of rigor and motivation. Terre des des hommes Foundation partnered with the software editor Wopata to develop a diagnostic support tool based on the IMCI directly intended for health workers. The Electronic Consult Record (Registre Electronique de Consultation - REC) guides the health professionals throughout the consult to help them strictly apply the IMCI, thus decreasing the number of diagnostic and treatment errors. It determines in real-time the illnesses of the patients as the health worker identifies the symptoms identifies the treatment associated to each diagnosed illness according to the IMCI and the medicines to be prescribed with their dosages. The REC is a web application. The learning curve is easy thanks to an interface specially designed for users with mostly no experience with computers. Despite the lack of internet connection, backup and consolidation of data at the level of the Ministry of Health is possible thanks to a secure export and synchronization mechanism via USB drives.The REC is installed on dedicated laptops (netbooks) with a customized operating system. The operator has complete control over hardware and software environments, simplifying maintenance operations. By integrating the REC into the health system of rural areas of Burkina Faso we are affecting all the stakeholders of the health system. We are able to participate to the improvement of patient care, to ease the work of field agents and to allow to the Ministry of Health to better monitor the implementation of its national strategies. Ultimately, to save more lives.