Probing the brain without surgery
A breakthrough European research project has developed a safe and simple approach that avoids surgery and its associated risks in order to help patients with traumatic brain injury (TBI). The BrainSafe project uses an innovative technology for non-invasive monitoring of intracranial pressure (ICP), the pressure inside the skull and thus the brain tissue and the surrounding fluid.
© Sebastian Kaulitzki fotolia
Until now ICP diagnoses have involved drilling a hole in the skull and placing a pressure sensor on the patient’s brain. This might expose the patient to infection (a 5% risk), bleeding, and leak of fluids or loss of other body tissue, pain, and hyperthermia as well as anaesthetic risks.
The BrainSafe technology is a fast and easy-to-use way of measuring ICP accurately and reliably. The system, based on ultrasound wave frequency technology, uses the same patient specific calibration free principle as a standard non-invasive blood pressure measurement.
“The cost, complexity and risk of current diagnostics means it is only used with the most critically ill patients, and not in the millions of patients who are at mild to moderate risk,” says BrainSafe project coordinator Edvardas Satkauskas from Vittamed, a Lithuanian company specialising in non-invasive ultrasonic technologies. “There is a clear and compelling need for a non-invasive ICP meter for routine clinical care,” adds Satkauskas.
The BrainSafe system includes a disposal headframe with an orbital pressure cuff and a separate reusable meter. It works by turning the ophthalmic artery – connecting the eyeball to the brain - into a natural pair of scales. A pressure cuff compresses the tissue surrounding the eye while a Doppler ultrasound beam measures the blood flow in both intercranial and extracranial segments of the eye artery. By simply raising the pressure on the cuff, the device increases the pressure on the extracranial segment until it matches that of the intercranial one.
The maximum pressure applied is equivalent to that of being under just 70mm of water. “The ICP meter is designed to simple and rapid use, requiring only minimal training. It is safe, reliable and accurate,” says Satkauskas. “This could have a huge impact on how we treat brain injuries,” explains Satkauskas.
Over 3 million people in Europe and the US suffer TBI annually, with a mortality rate of 4%. But only 20% of all TBI patients get access to the diagnostics of ICP. “BrainSafe could save 9,400 lives in Europe and increase the chance of survival and life span for an additional 136,000 patients with TBI yearly,” says Satkauskas.
Backed by a €895,517 grant from the European Commission, BrainSafe was run by a consortium of field experts in ultrasonic techniques, signal processing and hardware design for human interaction.
The BrainSafe project initially ran for two years until September 2011. The technology that helped design the prototype is currently being used for a follow-up project, BrainSafe II, to develop a robotic positioning system that could significantly shorten the learning curve of operators. The project partners are already testing the device with neurological and neuro-intensive care patients. “BrainSafe will be able to offer a diagnostics that can save lives and increase the chance of survival and life span for TBI and neurological patients,” concludes Satkauskas.