INDUSTRY

Up to 400 newborn Australian babies a year may have a better chance in life thanks to a revolutionary hearing test that goes on trial in Brisbane's Mater Hospital this month. The new test developed by researchers in the Cooperative Research Centre for Sensor Signal and Information Processing (CSSIP) takes Australia a step closer to the ideal of screening every baby at birth for hearing problems. Hearing impairment affects about 400 of the 250,000 Australian babies born each year and an estimated 20,000 worldwide. Its consequences can include lower IQ, learning, speech and behavioural problems. In many cases the harm is lifelong and the costs to both the individual and society high. "Testing only infants with pertinent risk factors detects only 25% of infants born with a hearing impairment by 12 months of age. The average age of diagnosis is around two years," says CSSIP team leader Dr Andrew Bradley. "It's extraordinarily difficult to tell if a newborn infant has hearing problems. By the time you find out - and this can be after several years - it may be too late to make good the learning losses caused by deafness. "Our technology enables newborn babies' hearing to be tested within days of birth, in a way that is very quick, totally safe, non-intrusive and very accurate." The research is part of a program funded by Queensland Health to develop leading-edge technology for diagnosing hearing problems in newborn babies and give them the best possible start in life. The CSSIP technology is a new generation advance on the widely-used Auditory Brainstem Response (ABR) technique which accurately measures the nerves' response to sounds through small sensors attached to the baby's head. It uses a random series of 'chirps' which have special mathematical properties that make them easier to pick up with the sensors on the baby's head, and separate them from the mass of other nerve signals using sophisticated digital signal processing and analysis. The test takes just 10-20 seconds to perform, compared with many minutes for existing technology on a sleeping infant. It can be performed using standard equipment, though Dr Bradley says the aim is to produce a small hand-held device, so hearing screening can be carried out on babies just about anywhere, including the Outback. "Because it is robust, quick and easy to use, it can be applied by medical staff in rural and remote communities as effectively as in a big city hospital like the Mater, where they test many babies every day. "The test is also sensitive enough to indicate how serious the hearing loss is. This means that babies with severe hearing problems can be diagnosed and treatment started much sooner, so avoiding learning problems later." Dr Bradley says that although the testing of newborn infants for hearing impairments is the immediate goal of the project, the technology has many other medical applications, including monitoring traumatic brain injury patients and detecting growths and cancers. It could also be developed to measure hearing loss in older patients. "ABR is used for a variety of medical applications in many countries of the world. Developing a superior ABR device that is not only faster but also more accurate in picking up and processing signals, is of great benefit," he says. "The commercial potential is also large. The current market for hearing screening for babies in Australia is $3.7 million a year and expected to grow to $12.5 million. "There are also big export opportunities, especially to the United States and Europe, where ABR is regularly used, though it will also be equally suitable for use in the Third World." The research addresses the Federal Government's National Research Priority two - promoting and maintaining good health.