Andreas Schulze-Bonhage, PhD, University Medical Center Freiburg, Freiburg im Breisgau, Germany, shares recent advances in mobile patient monitoring using wearable EEG sensors. The use of patient-reported seizure diaries to assess a patient’s condition lacks accuracy. In many cases, patients may suffer nocturnal seizures, be unaware during seizures, or not remember them after they occur. On the other hand, some patients may over-report when they are not sure if a seizure occurred. In-hospital monitoring also has its limitations due to the artificial environment, as well as timing and cost related issues. For this reason, ambulatory monitoring is becoming more and more prevalent in the epilepsy field. Both non-invasive EEG devices for short term monitoring and subcutaneous EEG recorders capable of ultra-long-term monitoring are showing promise for the assessment of seizure patterns and treatment efficacy. These approaches can be particularly beneficial in scenarios where seizures come with very few outwardly visible manifestations, such as absence seizures. This interview took place at the 14th European Epilepsy Congress (EEC) 2022 in Geneva, Switzerland.
Transcript (edited for clarity)
So in terms of EEG, there are new devices available, which allow to do ambulatory monitoring at least for a period of several days, which would be just fixed on the skin. So as you know, normally our investigations are limited to either 20 minute recordings in outpatient settings or long-term recordings in in-hospital settings. But these in-hospital settings are extremely expensive and the number of places are certainly limited...
So in terms of EEG, there are new devices available, which allow to do ambulatory monitoring at least for a period of several days, which would be just fixed on the skin. So as you know, normally our investigations are limited to either 20 minute recordings in outpatient settings or long-term recordings in in-hospital settings. But these in-hospital settings are extremely expensive and the number of places are certainly limited. And so we need better options also to see how the situation is in everyday life. And for this, these mobile EEG systems have become available now, which can be used with a limited number of electrode contacts, but wearable for the patient for a few days now, maybe up to a week.
But then we also have new devices which can be placed subcutaneously so that they are not visible at all to others and are not stigmatizing at all. And these devices can now be used for periods of months, even to more than a year. And this is really very interesting because these periods are the periods that we need in order to assess if our treatment approaches work. So to see if a change, for example, in medication improves seizure control, or if a change in a neurostimulation treatment would be effective.
And of course, depending on the seizure type and on the type of epilepsy, different devices may be the best to choose. So there are some seizures which can be very easily seen with wearables. So for example, generalized tonic-clonic seizures are very easy to identify nowadays with wearables, but there are other seizure types which have very little objective manifestations in terms of motor manifestations or even autonomic manifestations, like for example, absence seizures. And they are also very difficult to count for patients. And for those types of seizures, also for some temporal lobe seizures, these new implantable EEG devices are very interesting because then you really can see typical patterns of either, for example, three per second spike wave discharges in absences or rhythmic theta patterns with evolution of their amplitude, which are very typical for temporal lobe seizures. So it is possible with these new devices for EEG to monitor briefly or really over very prolonged periods of time how this seizure situation in patients is.