With many years experience in studying the rise and fall of pressure inside the heads of patients with severe head injuries, Professor Robert Allen and his team in the Signal Processing and Control Group at the University of Southampton's Institute of Sound and Vibration Research realised that in order to prevent brain damage what was needed was a method of anticipating changes in blood flow and particularly lack of flow.

Professor Allen and his team are using ultrasound to measure blood flow in the brain and to correlate the signal with the arterial blood pressure. This combination would then alert them if there were to be a change in blood flow. Ultrasound has
been of interest to researchers studying ways of measuring blood flow since the Norwegian engineer, Rune Aaslid, published a paper on its potential back in 1982.

'Swelling in the head can reduce blood flow,' comments Professor Allen. 'This system will alert us when that happens.'

Professor Allen and his team are working with colleagues at Southampton General Hospital to develop this research further and are currently testing their theories on groups of normal, healthy, volunteers.

'We believe this research could make a big difference to the lives of head injury patients,' comments Professor Allen. 'The signals provided will enable clinicians to ensure that the blood is flowing efficiently. This is crucial because, although many people survive head injuries, much of the damage occurs after the accident when the brain swells. Our technique will allow the medical profession to monitor the blood flow and to hopefully avoid any further damage to the patient.'