Microsystems for Medical Technology

Social demand is the driving force for new developments in miniaturised medical technology. Well-informed patients have high requirements in terms of improving the quality and safety of their lives. That can be achieved by a marked miniaturisation of medical devices, instruments and sensors that ensure that patients have less traumatic operations or can benefit from mobile monitoring systems. Microsystem technology provides potentials that meet those new social and medical requirements to the point. Major applications of microsystems are, for example, intelligent implants, patient monitoring and minimally invasive technologIntelligent Implants

A very important field in medicine is the development of intelligent implants based on microsystems technology. The pacemaker is a wellknown example. The new generation of devices do no longer stimulate the heart by inflexible, constant impulses only, but collect data like heart rhythm and react self-sufficiently with variable adjustments. In this way, this therapy is becoming more flexible and physiological. Meanwhile these systems can absolutely hold their own on the market. Implanted defibrillators that stimulate the heart directly in case of cardiac arrest have also been developed. A strong electric impulse restores the heart function. These devices are also successfully being introduced into the market. The leading German supplier in that field is the company Biotronik GmbH & Co.

Patient monitoring

A second very interesting application for microsystems is the continuous monitoring of physiological patient data. Therefore sensor systems inside or outside the body are needed. Up to now only stand-alone solutions are available, that means data remain stored in the device. Examples for ambulant devices with limited storing potential are 24-hour-bloodpressure measurement or 72-hoursblood sugar measurement. Using miniaturised sensors future systems in domestic surroundings should measure continuously and precisely blood pressure, intraocular pressure, electrocardiogram (ECG), level of blood sugar or respiratory sounds. The collected data will be wireless transmitted to the physicians. In this application field German companies like Siemens AG Medical Solutions, Dräger Medizintechnik GmbH, Philips Medical Systems, Weinmann GmbH, Fresenius Medical Care AG und B. Braun Melsungen AG play an important role.

Minimally Invasive Technology

Minimal invasive operation techniques would be unthinkable without microsystems technology. In this field microsystems in terms of miniaturised mechanical and optical systems were introduced to the operating rooms already 15 years ago. German companies like KARL STORZ GmbH & Co. KG, AESCULAP AG & Co. KG und Richard Wolf GmbH are international leading players in this market with endoscopes and intelligent instruments. In future miniaturised instrument systems will be improved by sensors generating tactile feedback to the operating surgeon. Based on this tactile feedback, navigation systems can support the surgeon in planning and operating.

German medical technology is in a good position internationally

Internationally, German companies rank among the leading suppliers of microsystems in medical technology. They play an important part in the worldwide turnover in this market segment ( 12 billion in 2002) [1]. Microsystem technology is a key technology for the development of innovative medical products. Its great importance helps to strengthen the medical technology industry in Germany. In 2004 the total turnover of this industry sector was 18 billion Euros, employing 100,000 people in 1,200 companies [2]. Because of highly increasing exports, a turnover of 25 billion Euros is expected in 2010 [3]. "Made in Germany" is still a good reputation for medical products. The share of the turnover in foreign countries is almost 55% and it is expected to rise steadily until 2010 [4]. This underlines the international competitiveness of the German medical technology industry. With 38% of all exports, the EU states are the main customers of medical technology from Germany, followed by the US with 20% [4]. Two German companies belong to the worldwide top ten: Siemens Medical Systems ranks fifth and Fresenius Medical Care AG seventh [4].

Beside industry, national research institutes are a guarantee for success. More and more of them are combining R&D in microsystem technology with biomedical engineering. Wellknown representatives are IMTEK, Prof. Stieglitz, University of Freiburg, ITIV, Dr. Stork, University of Karlsruhe, IWE, Prof. Mokwa, RWTH of Aachen, and Fraunhofer IBMT, Prof. Fuhr, St. Ingbert. University hospitals like the Charité in Berlin, Erlangen- Nürnberg and others apply biomicrotechnologies for innovative solutions in diagnostics and therapy.

Future developments will imply new challenges The main challenge to be coped with in the field of microsystem technology is the connection of technological components with the biological surroundings. In future, top innovations can be achieved in the following applications:

* Enhancement of active implants by biocompatible coating
* Intelligent drug targeting according to data determined by microsystems
* Linking of data for complex diagnostics in an environment close to the patient without necessarily consulting a physician or going to hospital
* More complex and individual analysis of biological, chemical, pharmacological, toxicological and medical data .. Continuous advancement of imaging systems for instrument navigation and better acquisition of parameters relevant to therapy