Philippe Jourand

Design and fabrication of a low cost implantable bladder pressure monitor

In the frame of the Flemish Community funded project Bioflex we developed and fabricated an implant for short term (< 7 days) bladder pressure monitoring, and diagnosis of incontinence. This implant is soft and flexible to prevent damaging the bladder’s inner wall. It contains a standard flexible electronic circuit connected to a battery, which are embedded in surface treated silicone to enhance the biocompatibility and prevent salt deposition. This article describes the fabrication of the pill and the results of preliminary cytotoxicity tests. The electronic design and its tests, implantation and the result of the in-vivo experimentation will be presented in other articles.

A Differential Pressure Approach to Spirometry

This paper presents the design, implementation and measurements of a spirometer based on differential pressure sensing. A system which fulfills the last medical standard specifications has been designed exploiting the Venturi tube principle. A fully operating prototype has been tested, and data have been subsequently analyzed. Air flows up to 14 L/s can be measured with an accuracy of 0.2 L/s. Data acquisition software and user interface were developed.

Textile Integrated Monitoring System for Breathing Rhythm of Infants

Monitoring the breathing rhythm of infants during sleep can be life saving. But today, most monitoring systems lack patient comfort. In this paper an innovative biomedical monitoring system with textile integrated sensors is developed and tested. Monitoring breathing activity is used as a case study, yet, the platform is extendable by an architecture that can contain up to twenty modular sensor channels, divided in several sensor islands. It is therefore useful for all kinds of (biomedical) applications. Flexible carriers for the electronic circuit lead to better textile integration and more wearing comfort. Quantification of breathing rhythm and volume is performed by accelerometers. These breathing signals are calculated on the basis of the technique that the angle of the gravitation vector in the coordinate systems of the accelerometers changes, because of movement of the abdomen. Differential use of two accelerometers makes this measurement insensitive for movement and posture. The comparison of these signals with a spirometer yields promising results.

In vitro cytotoxicity testing and the application of elastic interconnection technology for short-term implantable electronics

An electronic device was fabricated consisting of 2 flexible electronic circuit islands, interconnected by a 7 cm long elastic interconnection, which could be elongated for at least 50%. This interconnection was based on gold conductor tracks following a 2-D spring pattern, embedded in a biocompatible silicone elastomer. The complete device was embedded in the same silicone elastomer. An in vitro cytotoxicity extraction test, executed on small test-samples in accordance with the ISO 10 993-1 guidelines, revealed that the applied silicone encapsulation to these samples functioned as a good seal for at least 8 days.

Evolution in Bladder Pressure Measuring Implants Developed at K.U.Leuven

Bladder pressure monitoring devices have been a topic of great interest for the past two decades. Three devices developed at ESAT-MICAS in this time are reviewed, showing the evolution of these devices. Two of these devices are diagnostic tools small enough to be inserted into the bladder cavity through minimal invasive cystoscopy. The third device is a long term bladder pressure monitoring implant that, if used to drive an artificial sphincter muscle, forms a urological pacemaker that could diminish or rule out urinary incontinence. After a summary of the three devices, recent results are presented from one of the diagnostic tools.