A softer approach to brain monitoring27 October 2023
Abnormal brain activity can be a tell-tale sign of neurological disease, but detecting it is more of a marathon than a sprint. Several limitations, from technology to convenience, prevent clinicians from detecting the signals needed to make a diagnosis, and the result is that patient treatment is delayed. There could be a glimmer of hope for the long-term monitoring necessary to avoid these mistakes, however. Sophie Ash speaks to Jennifer Gelinas, assistant professor of neurology, electrical, and biomedical engineering, and director of the Epilepsy and Cognition lab at Columbia University Irving Medical Center, to find out how developments in materials science could make constant monitoring a reality for doctors and patients.
It’s notoriously difficult to diagnose neurological diseases. Abnormal brain activity can’t always be pinned down to a single cause, and there’s always a chance short-term clinical investigation will miss vital signs of disease. While constant monitoring is an option, this comes with an array of limitations of its own. “The symptoms of neurological disease are typically transient,” says Jennifer Gelinas, assistant professor of neurology, electrical, and biomedical engineering and the director of the Epilepsy and Cognition Lab at Columbia University Irving Medical Center. “This means they might not show themselves in a particular window of observation at the hospital, making it easy to miss an important diagnosis like multiple sclerosis or epilepsy.”
One of the existing options Gelinas herself has used many times is EEG (electroencephalogram) testing. What’s great about EEG is that it allows clinicians to see a snapshot of activity in the brain without requiring an invasive procedure. What’s not so great is that EEGs provide very limited information about deeper parts of the brain because the technology only allows for surface-level investigation. In practice, this means clinicians can’t home in on a specific, small area of concern and take a closer look. Another major downside of EEG testing in patients with suspected or known neurological conditions is that the duration in which you can measure brain activity is limited to around 30 minutes each time. What happens if there aren’t any symptoms or abnormalities presenting themselves at this time? Clinicians, and thus patients, are left in the dark.
MRI (magnetic resonance imaging) is another helpful tool at neuroscientists’ disposal, but this too has its limitations. “MRIs can certainly help to find abnormalities that have changed a patient’s brain structure,” explains Gelinas. “However, like EEG testing, the reports they generate are only from a snapshot in time. We also can’t rule out a neurological disorder based on MRI results alone because the test doesn’t give us any information regarding how the brain tissue is actually functioning.”
While adults can lie still for the 30 minutes necessary to gather MRI data, this is a near-impossible task for young children, which introduces anaesthesiaassociated health risks to the patient. What’s more, wait times to undergo an MRI are often lengthy; machines are expensive and not easily accessible by everyone; expert personnel are required to operate and interpret MRI scans; and existing implanted devices can easily disrupt how the data is read. All in all, clinicians and patients are left feeling frustrated by the lack of reliable information at hand.
In an attempt to widen the window of time in which they can observe a patient with a possible brain abnormality, clinicians often have to resort to prescribing overnight hospital stays. However, this requires numerous staff to be on hand to monitor the patient, which isn’t feasible or sustainable in the vast majority of cases.
There are four primary reasons why constant monitoring hasn’t been possible from a neurological standpoint: Patient discomfort, incompatibility with daily life, limited data quality, hardware and material limitations. The discomfort caused by traditional medical devices in this space has been a significant hindrance to sustained monitoring of neurological activity. Patients find these devices bulky, heavy, and irritating, which often leads to them scratching attachment sites and even dislodging the devices entirely to stop them interfering.
With traditional devices always getting in the way, it’s extremely difficult for patients who require constant monitoring to be compliant. Being tethered to monitoring equipment makes it almost impossible for patients to lead their normal lives and conduct everyday activities. This makes long-term observations very impractical for clinicians and researchers, as they rely on patient compliance to be able to gather data.
The quality of data gathered through such monitoring devices is also far from ideal. Every time a patient scratches or dislodges a device, the data it’s collecting becomes less accurate and valuable to the clinician. For example, signals get degraded and may end up lost in translation. With a limited ability to interpret such data correctly, it’s not easy to provide appropriate and timely care plan recommendations to patients. “If the data is bad enough, it’s going to interfere with one’s ability to provide a diagnosis,” says Gelinas. A large attributing factor to the unfeasibility of constant monitoring in neurology patients has been limitations in hardware and materials used in monitoring devices. Most devices are built using rigid materials, such as silicone and metal, which are not biocompatible. This means that in order to come into contact with a patient’s bodily tissues, the materials must be encapsulated, making them uncomfortable to wear. Moreover, the cables and wires required to connect devices to external monitors further contribute to the mobility restrictions patients face while being monitored.
The quest for more comfortable and unobtrusive monitoring solutions has quickly become an urgent priority for researchers, healthcare providers, and patients alike. Fortunately, times are changing, and we are now at a major turning point in long-term neuroscience monitoring. “Recently, there’s been an explosion in the wearable electronics space,” says Gelinas. “Advances in material science and engineering are bringing softer, more compatible materials into the forefront for device development.”
A softer alternative
This technological breakthrough has paved the way for comfortable, non-invasive long-term monitoring of numerous physiological parameters, including brain activity. “These new, soft devices can be affixed to a patient’s forehead or wrist with a very small form factor that can read out information wirelessly to monitor sleep patterns, monitor heart rhythms, and do basic EEG,” explains Gelinas. “So, we’re really moving in the direction of being able to monitor in real-time.”
Gelinas and her team have been spearheading research and development in long-term neuroscience monitoring for some time now. Their work primarily focuses on leveraging novel materials – in particular, organic electrons – in an effort to create high-precision medical devices that offer a wealth of information without compromising patient comfort. “If we can leverage organic electrons, we could make medical devices with very high precision that would be extremely useful to neurologists and their patients,” says Gelinas.
Organic electrons are a class of materials capable of interacting with both electrons and ions to offer an unprecedented sensitivity to physiological signs within the body. These materials are not only biocompatible but also comfortable when in contact with bodily fluids, making them ideal for interfacing with active tissues and giving them the potential to advance neuroscience research.
“We wanted to make a novel class of devices that gives better diagnostics without exposing patients to as much risk,” says Gelinas. With this intent, Gelinas’ team has already made huge strides in developing soft organic electronic devices for neuroscience monitoring. The device they are currently testing can listen, process, and transmit brain activity wirelessly, all while being fully implanted within the body. This remarkable innovation eliminates the need for external cables or wires entirely, which could change the course of neuroscience monitoring forever.
One of the most impressive aspects of Gelinas’ team’s research is that their device allows one to see down to the activity of the individual neurons in a person’s brain – something previously claimed to be scientifically unattainable. “This gives us a lot more power and precision for identifying when, where, and how things are going wrong in the brain,” explains Gelinas.
Epilepsy and beyond
The team’s primary disease state focus, thus far, has been on epilepsy: a neurological disorder marked by sudden recurrent episodes of sensory disturbance, loss of consciousness, or convulsions. Epilepsy was an obvious place to start for several reasons: There is a strong pre-existing knowledge base on epilepsy, and patients with this condition have already shown positive responses to neurostimulation; there is a lot of room for improvement in the monitoring devices currently used with epilepsy patients – potential that Gelinas’ team can tap into; it allows them to take a patient-centric approach to research, as epilepsy already has a well-defined patient population to study closely.
While organic electron-fuelled neurological monitoring devices show enormous potential in improving clinical outcomes for people with epilepsy, Gelinas doesn’t want to stop there. The team envisions a broader future for their technology, intending to apply their findings to other neurological disorders over time, ultimately revolutionising the entire field of neuroscience.
Gelinas and her team began their research using animal models, which allowed them to test the feasibility and effectiveness of their soft organic electronic devices safely before moving on to human subjects. The next critical step for Gelinas will involve more thorough testing to minimise risks and validate their devices’ real-world clinical application. “What we’re working towards right now is making sure we have full safety and appropriateness for human use,” she says. From there, the team will scale up the production of their devices so that they can meet the demands of human clinical trials.
The ultimate goal is to make a positive impact on patient care by providing improved diagnostics and therapies for neurological conditions. With the development of soft organic electronic devices, patients may soon be able to benefit from comfortable, precise, and non-invasive monitoring solutions, opening new doors for accurate diagnoses and improved treatments in the field of neurology.