Who is Who
The Scientific Advisory Board: Ilias Tatchtsidis
Ilias Tachtsidis, PhD, is a Professor in Biomedical Engineering at University College London (UCL). He is a senior member of the Biomedical Optics Research Laboratory and leads the MultiModal Spectroscopy group and Metabolight. His team is developing new optical monitoring instruments and techniques for medical applications, exploiting the optical properties of natural chromophores, the molecules responsible for colour, as in the haemoglobin. By using safe and non-ionising radiation, they can be continuously monitored at the bedside of patients and provide useful information.
We had the chance to chat with Prof. Tachtsidis about his research, how he got involved in TinyBrains and his vision of these technologies. He has talked about the growing community of researchers working in near-infrared spectroscopy, a brain imaging method that measures light absorbance and can provide an indirect measurement of brain activity.
So Ilias, how did you become involved in TinyBrains?
Ilias Tachtsidis: I’ve known Turgut since he was in Penn lab in the USA, and we are both now part of the community of scientists working with near-infrared spectroscopy. We collaborated in quite a few grant writing, and we also have an ongoing collaboration as part of my Medical Research Council Grant here in the UK.
You’ve mentioned you are part of the community of researchers working in near-infrared spectroscopy, what is your current research?
I.T. Near-infrared spectroscopy is the umbrella for many other technologies. The one I’ve been working on is broadband near-infrared spectroscopy, meaning multiple wavelengths of light. In our lab, we are trying to measure not only the oxygenation and hemodynamics in the brain, but also the metabolism. We try to quantify more chromophores in the brain tissue, beyond the haemoglobin that carries the oxygen, we are also trying to monitor a molecule in the mitochondria, which uses that oxygen to produce energy. And for that, we need this particular type of technology.
Are you focusing on any particular medical condition or group?
I.T. Our works spans different areas of applications, but during the last 10 years, we’ve been focusing on newborn infants, in particular those born with a condition called neonatal encephalopathy. In this condition, during the babies’ delivery or in the uterus, the blood flow to the baby’s brain is suppressed or seized causing a brain injury, what we call hypoxic ischemia, meaning that there is not enough oxygen and blood flow to meet the brain’s needs. Once these babies are born, they are blue and need oxygen to start breathing. But the initial damage in the brain has happened, so the issue that we have is: Can we actually measure this damage? Can we actually quantify it as early as possible and hence be able to inform our clinical colleagues to avoid secondary injury? That’s when our technology comes in. As a bedside technology, we try to provide this information as quickly as possible, about three hours after birth, and we try to measure the brain and give information to the medical team.
Does the technology scan the whole brain?
I.T. It is a very good question! The condition I was talking about is a global pathology, so it affects the whole brain. We have different instruments that can look at two or three locations of the brain, but we also have others that can actually map the entire brain. We sometimes use these, trying to see if we can identify if there are some centres that have been more affected than others. For example, a lot of these babies develop a condition that is called cerebral palsy, so we know a big part of the injury is in the brain area that controls motor function. The neonatal intensive care units are a very sensitive area, so we need to be able to monitor the babies easily and give information as soon as possible. We try to balance two things; ease of use, and obtaining the appropriate clinical information.
Are you trying to obtain the data in real-time?
I.T. Yes. The information is collected in real-time on the laptop. What is important is how we deal with that information. One thing is the collection of the data, and the other is how we transform or translate this data into clinical information because that’s what the doctors need. For example, we have recently identified a very good marker of brain function is the relationship between brain oxygenation and brain metabolic signals. We have found this works as a biomarker for babies within a few hours-days following birth. That’s the challenge that we have, building equipment that doesn’t interfere with the clinical care and collects the data in a way that also provides information to the medical team, so it allows them to act and communicate with the families.
Is it implemented in neonatal intensive care units?
I.T. We’ve been using this particular technology for about eight years now, we’ve done measurements on more than 100 babies. We are still collecting data as we speak, and our focus is still their first hours and days of life. Our clinical team of neonatologists at University College London Hospital have been instrumental in deploying and using our technologies and techniques.
Do you think that this technology might provide an improvement on other technologies?
I.T. My hypothesis is that the combination of the measurements gives you more information than the individual sum of these measurements. The challenge that we have as engineers is how we make these instruments to give the combined measurements of oxygenation, blood flow and metabolism, the three main markers that the clinical teams also understand. So, we need to provide them with equipment that is not very intrusive, in a way that compiles the measurements to give the clinical information. How we do it in terms of maths, signals and engineering is another challenge that we have, to choose the tools to move from data integration to real clinical information. One of the collaboration grants we had, funded by the Medical Research Council of the UK, was to develop the broadband near-infrared spectroscopy and the diffuse-correlation spectroscopy a method that has been developed by Turgut at ICFO. It is currently being tested in newborn babies with neonatal encephalopathy in ICUs in the University College London Hospitals or UCLH.
Besides clinical care, is there any work done related to basic science?
I.T. Yes, we also do a lot of preclinical work, because I think you need to establish a baseline before starting to transfer the technology to the clinic. Understand how our measurements are linked with others that the clinical team knows, and also what they can tell in terms of mechanisms of action. For example, if I talk with the clinical team and I tell them, “I measure the metabolism” they will say “how do you do that?” and I tell them, I measure the oxidation in the mitochondria, some of them will remember the biochemistry lessons back in college and say oh yes, I know what that is. But the thing is that they won’t understand how that measurement is related to others they might be more aware of, for example measuring ATP, phosphocreatine or inorganic phosphate, etc. but they might not have heard in particular what our measurement is. So, a lot of our work is actually to establish this baseline and give some information about how our near-infrared metabolic measurements are related to other measurements of metabolism such as magnetic resonance spectroscopy or positron emission tomography ones.
Do you foresee any other applications for these technologies in the future?
I.T. I definitely see some room for looking at a stroke in adults. I also think there is an opportunity in adult cardiac surgery, I think the brain changes when you undergo cardiac bypass, and I think it can offer an interesting biomarker related to cognitive function. And also, cardiac surgery and stroke involve a large population of adults. And then, the other area that I think we can offer something to is dementia and Alzheimer’s disease, where there are hypotheses of the mechanism of actions involving vascular issues, so again this would be about providing early markers.
His research group has given two of the broadband near-infrared spectroscopy devices to Switzerland to look at cognitive decline, another to Germany to look at Parkinson’s disease, another one to Columbia to look at mental health disorders, particularly schizophrenia and anxiety, and another one in Sidney where they are doing children cardiac surgery. Inside the UK, they are measuring in hospitals seizures, epilepsy, multiple sclerosis and retina pathologies in adults. They also do research about babies and toddlers developmental assessment.