Empatica smart watch receives FDA clearance for seizure monitoring
February 13, 2018
Massachusetts-based Empatica says its Embrace has become the world’s first smart watch cleared by the FDA for use in neurology.
Embrace uses AI and advanced machine learning to monitor for the most dangerous kinds of seizures, known as grand mal or generalised tonic-clonic seizures, and send an alert to summon caregivers' help.
In a multi-site clinical study, 135 patients diagnosed with epilepsy were admitted to epilepsy monitoring units for continuous monitoring with video-EEG, while simultaneously wearing an Empatica device. From these patients, 6530 hours of data were recorded over 272 days, including 40 generalised tonic-clonic seizures.
Embrace's algorithm was shown to detect all the seizures. The trial used the gold standard of comparing with seizures clinically labelled by at least two out of the independent epileptologists, who examined the video-EEG data without seeing any data used by Embrace.
Embrace stands apart from other seizure detection systems in that it measures multiple indicators of a seizure. Its unique property is its use of electrodermal activity (EDA), a signal used by stress researchers to quantify physiological changes related to sympathetic nervous system activity, also known as the fight-or-flight response. Embrace has been approved in Europe as a medical device for seizure monitoring and alert since April 2017.
According to recent estimates by CDC1, 1.2% of the US population suffers from epilepsy, amounting to around 3.4 million patients, including 470,000 children. More than a third of these patients do not respond to medication to control their seizures, while another third are only partially responsive to medication.
Generalised tonic-clonic seizures result in a loss of consciousness and can leave the person in a state of confusion for some time afterwards. Traditionally, clinical trials have had to rely on patients to self-report in a diary when a seizure happens, a process known to be inaccurate. Over 40% of the most dangerous generalised tonic-clonic seizures are not reported, but Embrace's sensitivity makes seizure reporting easier and more accurate. The bracelet also sends an alert immediately to a caregiver, to bring help at the time of need.
The field has been waiting for decades for a biomarker alternative to wearing an EEG, that can be automated, used outside of the hospital, and isn't bulky or cumbersome to wear.
Orrin Devinsky, one of the world's foremost experts in epilepsy, and director of the epilepsy centre at New York University, has seen the shortcomings of traditional systems during his 35-year career.
"The FDA approval of the Embrace device to detect major convulsive seizures represents a major milestone in the care of epilepsy patients,” said Devinsky. “Tragically, more than 3000 Americans die each year from sudden unexpected death in epilepsy (SUDEP) and the Embrace offers the potential to alarm family members and caretakers that a tonic-clonic seizure is occurring. The scientific evidence strongly supports that prompt attention during or shortly after these convulsive seizures can be life-saving in many cases."
Seizure monitoring research started with Empatica’s chief scientist Rosalind Picard at the MIT Media Lab, where she is director of the affective computing group and later at Boston's Children Hospital.
"It's been quite the journey,” she said. “We have worked for years building wearable stress and emotion sensors, and then accidentally discovered we could pick up changes in the skin elicited by brain activity related to the most dangerous kinds of seizures. It has been very meaningful to see this technology move from the lab into the most accurate, beautiful and easy to use sensor on the market."
Empatica initially launched Embrace through a crowd-funding campaign in 2015, focusing heavily on high-quality design. Matteo Lai, co-founder and CEO of Empatica, said: "Medical devices face a huge problem: they're usually too bulky and uncomfortable, and people simply don't want to wear them. Empatica took a different path. We wanted to design the world's first medical device that could win a design award, while being used as a lifesaving product. Patients actually love Embrace and are proud to wear it. We think this has been one of the keys of its success and an interesting lesson for healthcare. Cutting edge technology and good design need to go together."
Empatica is a MIT Media Lab spin-off, with offices in Cambridge, Massachusetts, and Milan, Italy. It has 45 employees and designs everything in-house. It also manufactures a research device, the E4, which has been sold to thousands of institutional partners, including hospitals, research institutions and pharmaceutical companies. It has been used in studies for stress, sleep, migraines, depression and many other conditions.