Detecting brain dysfunction in
infants before permanent
The Public Health Agency of Canada has identified pre-term birth as one of the most important perinatal health problems in industrialized nations. Statistics show it accounts for 75-85 per cent of all perinatal deaths in Canada. Advances in neonatal intensive care practice have improved the survival rate of preterm infants, but this success story has been accompanied by an increase in the incidence of brain injury.
Lawson Health Research Institute’s Drs. Jeffrey Carson and Keith St. Lawrence are developing technologies to detect evidence of brain dysfunction before permanent damage occurs. According to Dr. St. Lawrence, their focus is on portable optical imaging technologies that can be used in the neonatal intensive care unit.
Many factors contribute to preterm brain injury, but a drop in blood flow to the brain is one of the leading causes. In some cases, ultrasound imaging can show the results of brain injury, but in many cases injuries go undetected.
Drs. Carson and St. Lawrence plan to use a mix of optical technologies to identify areas of brain injury sooner and with better accuracy. Optical technology uses light over a range of colours to distinguish blood content in the brain to detect adverse changes in blood flow. These technologies are inherently safe to patients and can be taken directly to the bedside, where they can have the most impact.
The researchers plan to combine three types of optical technologies into a hybrid platform: time-resolved near-infrared spectroscopy (TR-NIRS), diffuse correlation spectroscopy (DCS), and photoacoustic imaging (PAI). TR-NIRS utilizes ultra-fast lasers and detectors to examine the deep tissues of the brain, and can be used to make intermittent measurements of blood flow in the brain. DCS uses ultra-stable lasers and sensitive detectors to continuously monitor the flow of blood at the tissue level (cerebral perfusion). Both TR-NIRS and DCS provide individual measurements that cover vast regions of the brain, and PAI will gather detailed supporting images. The researchers believe that combining the three technologies will result in a much more capable hybrid optical system to rapidly and continuously monitor the early appearance of brain injuries in preterm infants.
Drs. Carson and St. Lawrence plan to take advantage of their combined years of experience in each of the optical technologies to develop and test the new hybrid system. As integrating TR-NIRS, DCS and PAI is a major challenge, they have recruited top researchers and medical specialists to help them reach their goal. , Scientists from Western University and the National Research Council in London, Toronto, and St. Louis will help them develop techniques to combine the data from each technology.
Almost 10 per cent of babies in Canada are born premature and for those babies born with birth weights less than 1 kg, 10 per cent will develop cerebral palsy and 40-50 per cent will have cognitive and behavioural deficits. “We are hopeful that by combining optical technologies to monitor the early signs of brain injury at the bedside, the medical teams caring for these infants will have more time to intervene with treatment and reduce the possibility of life-long disabilities in these fragile patients,” says Dr. Carson.
Their study, called “Hybrid biomedical Optical Platform for Improved Detection and Management of Brain Injury” was funded through a $265,241 grant from the Canada Foundation for Innovation’s (CFI) Leaders Opportunity Fund. If their work goes as planned they will be in a position to obtain regulatory approval and introduce the system into the neonatal intensive care unit within 5 years.