Mediterranean Conference on Medical and Biological EngineeringThe IFMBE VII Mediterranean Conference on Medical and Biological Engineering was held at Mitzpe Ramat Rachel Kibbutz Hotel, Jerusalem, from 17 to 21 September 1995. Under hazy blue Mediterranean skies of early autumn, in one of the world's most historically significant cities, who can be surprised that the attendance in the sessions of this meeting was notably less than the number of registrants ? In his opening address, the recently elected Mayor of Jerusalem indeed encouraged the participants to make time to explore the city, which his eminent predecessor Teddy Kollek had regenerated in such spectacular fashion over 29 eventful years in office. The city is 'en fête' this year, celebrating 3000 years since King David captured Jerusalem and made it his capital. The city is also awaiting negotiations with the Palestinians to determine its future organisation within the new concord. Professor Sam Sideman, Conference Chairman, welcomed all those who had come to Jerusalem, and encouraged the conference delegates to make the essential link between innovation and practical solutions. The IFMBE President Professor Fumihiko Kajiya, from Okayama, Japan, reported the breadth of activities of the Federation; somewhat ironically, the delegates trickled in during this lecture due to a traffic jam caused by the first-ever visit of a Japanese Prime Minister to the city of Jerusalem. Those absent from sessions missed some excellent plenary lectures and a high standard of scientific presentation. Many of the presentations alluded to the highly significant advances in molecular biology and cellular engineering. It was therefore particularly appropriate that the first plenary lecture by Professor Bob Nerem, USA, provided an informed summary of the cellular engineering field. Describing this as 'the engineering response to the biological revolution', he concentrated on the cell's response to its mechanical environment. Experimental quantitative observation and modelling will provide the understanding necessary for tissue engineering, which in the USA accounted last year for $250 million of R&D spent on 'skin' products alone. Other developments into the pancreas, cartilage and cardiovascular components are expected to follow. One important issue to tackle is the control of cell proliferation, which may come from genetic engineers. Professor Friedman's plenary lecture on the training of medical engineers will be reported in the next issue of IFMBE News, because it raises some interesting questions for us all to consider. IFMBE Vice-President, Jean-Pierre Morucci, France, chose to address an older technology which is the subject of renewed interest. Impedance imaging is a simple method of 'injecting' small currents into the body via surface electrodes, then determining impedance from the voltage picked up across the same, or another pair of, surface electrodes. Impedance images generated from arrays of these electrodes reveal internal tissue structure akin to a low-resolution X-ray scan, but without the associated bio-hazards. The resolution at present is approximately 10% of the diameter, e.g. 40 mm across the thoracic cavity. Applications proposed for this system include breast tumour detection and functional studies of gastric emptying, lung ventilation, bladder filling and blood vessel compliance. Electrical impedance tomography might also be useful for functional brain scanning. With European funding, a concerted action programme (CAIT) is underway, lead by Brian Brown and David Barber at Sheffield, UK. Questions at the end of Professor Morucci's presentation tackled current concerns about the effects of electrical fields; those used in impedance imaging are much higher frequency than the fields implicated in public health issues, and no ill effects to date have been noted. The controlled delivery of drugs by use of polymeric systems was the topic addressed by Professor Kost, Ben Gurion Hospital, Israel. In attempts to maintain drug levels in the body between the minimum effective level and the toxic level, there are four basic methods that have been developed: diffusion such as a membrane bag containing the drug in solution; chemical reaction such as biodegradable polymers which carry the drug; swelling-controlled mechanical release of drugs; and osmotic pumping by water pressure which forces the drug from a reservoir. These methods have initially been developed for 'zero-order' control, i.e. maintaining a constant drug level. The next major step forward will come with modulated release, perhaps in response to physiological needs. A prime example might be the release of insulin in response to glucose level. Regulation might be external, e.g. by magnetism or ultrasound, or self-regulatory through PH level, enzyme action competitive bonding and so forth. Ultrasound holds a particular interest. It has been demonstrated to enhance microsphere delivery, as well as offering potential for transdermal delivery due to enhanced skin permeability. The latter 'sonopheresis' could result in injectionless delivery of, say, insulin from a wrist-watch type of device. In a wide-ranging overview of organ replacement, Professor Bonomini, Italy, named molecular biology and organ replacement as two of the three recent important forms of life (computer science was his third). Basing his following remarks on the well established renal transplantation programme, the current clinical statistics gave cause for reflection. Morbidity is one often quoted figure, but we also need to consider disability and employment: only 20% of dialysis patients are at work, 40% are clinically depressed and 60% have physical dysfunction. This reveals some unwelcome truths in renal replacement therapy, and the bio-ethics of using live donors is now questioned. The future was proposed to lie in artificial replacements firmly based on biological models. This will lean heavily on biosensor development and cellular engineering to improve the design, and on genetic engineering to gain biological tolerance. For the rest of the conference, three parallel sessions were held, covering everything from imaging to rehabilitation. With the small informal nature of these sessions, plus two excellent social events held in stunning museums, and a walking tour of the old city, there was adequate opportunity for making good contacts which went some way to compensate for the lack of depth in any one field. The next Medicon is planned for Cyprus in 1997. MARILYN LORD | ||