Publication date: 15/01/2019
Imec, the world-leading research and innovation hub in nanoelectronics and digital technology and Ghent University, together with Medtronic and other CARDIS project partners, have developed a prototype medical device based on silicon photonics for the screening of arterial stiffness and for the diagnosis of cardiovascular diseases such as arterial stenosis and heart failure. A clinical feasibility study with 100 patients has been successfully completed by INSERM at the Georges Pompidou European Hospital in Paris, France.
Cardiovascular disease (CVD) is among the leading causes of death globally. Early identification of individuals at risk allows for early intervention to halt or reverse the pathological process. Assessment of arterial stiffness by measurement of aortic pulse wave velocity (aPWV) is included in the latest guidelines for CVD risk prediction and it is a key marker for hypertension. However, no tools are available today to easily screen a large number of patients for arterial stiffness at a GP’s office. As a consequence, many individuals remain undiagnosed.
In the Horizon 2020 project CARDIS, imec, Medtronic, and 7 other partners, have developed a prototype mobile, low-cost, point-of-care screening device for CVD. The device aims for measurement in a fast, reproducible and reliable way with minimal physical contact with the patient and minimal skills from the operator. The operating principle of the device is Laser Doppler Vibrometry (LDV), in which a very low-power laser is directed towards the skin overlying an artery. The skin’s vibration amplitude and frequency, resulting from the heart beat, are extracted from the Doppler shift of the reflected beam. The device includes two rows of six beams, thereby scanning multiple points on the skin above the artery in parallel.
At the heart of the system is a silicon photonics chip containing the optical functionality of the multi-beam LDV device. The CARDIS chip was designed by the Photonics Research Group, an imec laboratory at Ghent University, and prototyped through imec’s silicon photonics technology platform iSiPP50G, and has been implemented using advanced optical packaging approaches developed at the Tyndall National Institute in Ireland. The system has then been integrated into a handheld device and validated for human use by Medtronic.
A clinical feasibility study at the Georges Pompidou European Hospital in Paris has collected a substantial clinical dataset, both from healthy subjects as well as from patients with cardiovascular conditions. The quality of the device readings was found to be very good and adequate measurement results could be obtained in all subjects. Also, the measurement data and variability within sessions were in line with data and variability acquired by reference techniques. A full dataset is now available and in-depth analysis will be performed both at INSERM and at the biomedical engineering department of Ghent University with the support of Medtronic. Moreover, further clinical feasibility studies are planned in the Academic Hospital of Maastricht (The Netherlands).
“The CARDIS device was well accepted by all patients, and it was considered useful and well tolerated,” states Dr. Pierre Boutouyrie, the cardiologist in charge of the feasibility study. “Feasibility of signal acquisition is excellent since a useful signal was acquired in 100% of the patients. Tolerance was excellent too, the time to get useful signals was less than 10 min, and patients barely noticed that a measurement was performed.”
Roel Baets, head of the Photonics Research Group (imec/UGent), concludes: “Silicon photonics is a powerful technology that combines the unique sensing capabilities of photonics with the low-cost and miniaturization capabilities of silicon semiconductor technology. It’s exciting to know that our silicon photonic chip and prototype medical device hold the promise to change the lives of so many patients with cardiovascular diseases.”
In a next step, a small series of the device will be produced to perform a clinical feasibility study on a larger group of patients and over a longer period of time. If this feasibility study demonstrates the ability of the technology to detect cardiovascular diseases at an early stage, high volume production can be initiated. One of the benefits of the silicon photonics technology is that at high volumes, the chip can be produced at low cost.
The silicon photonic chips (above) and prototype medical device (below) to perform Laser Doppler Vibrometry on a patient’s skin to deduce metrics for arterial stiffness and to diagnose cardiovascular diseases.
The CARDIS project has received funding from the European Union's H2020 Programme for research, technological development and demonstration under grant agreement No 644798. Coordinated by imec and Medtronic, the project partners include SIOS Messtechnik GmbH (Germany), Tyndall (Ireland), Ghent University (Belgium), INSERM (France), Queen Mary University of London (UK), Maastricht University (The Netherlands) and Fundico (Belgium).
Imec is the world-leading research and innovation hub in nanoelectronics and digital technologies. The combination of our widely acclaimed leadership in microchip technology and profound software and ICT expertise is what makes us unique. By leveraging our world-class infrastructure and local and global ecosystem of partners across a multitude of industries, we create groundbreaking innovation in application domains such as healthcare, smart cities and mobility, logistics and manufacturing, energy and education.
As a trusted partner for companies, start-ups and universities imec brings together more than 4,000 brilliant minds from over 85 nationalities. Imec is headquartered in Leuven, Belgium and has distributed R&D groups at a number of Flemish universities, in the Netherlands, Taiwan, USA, China, and offices in India and Japan. In 2017, imec's revenue (P&L) totaled 546 million euro. Further information on imec can be found at www.imec-int.com.
Imec is a registered trademark for the activities of IMEC International (a legal entity set up under Belgian law as a "stichting van openbaar nut”), imec Belgium (IMEC vzw supported by the Flemish Government), imec the Netherlands (Stichting IMEC Nederland, part of Holst Centre which is supported by the Dutch Government), imec Taiwan (IMEC Taiwan Co.) and imec China (IMEC Microelectronics (Shanghai) Co. Ltd.) and imec India (Imec India Private Limited), imec Florida (IMEC USA nanoelectronics design center).
About Photonics Research Group
The Photonics Research Group in the Department of Information Technology of Ghent University is an associated lab of imec and performs research in the field of photonic integration – more specifically silicon photonics – and its applications in information and communication technology, in sensing and in life sciences. With its 80 researchers the group has a leading international role in the field and is also very active in graduate education in photonics and in industrial spin-off resulting from its research. More information can be found at www.photonics.intec.ugent.be.
Medtronic plc (www.medtronic.com), headquartered in Dublin, Ireland, is among the world's largest medical technology, services and solutions companies - alleviating pain, restoring health and extending life for millions of people around the world. Medtronic employs more than 86,000 people worldwide, serving physicians, hospitals and patients in more than 150 countries. The company is focused on collaborating with stakeholders around the world to take healthcare Further, Together.
Medtronic Bakken Research Center (BRC), founded by Medtronic in Maastricht in 1987, starting with 45 employees and now reaching 325, is the research facility involved in CARDIS. Especially clinical study activities have grown substantially, now ranging from small exploratory studies with one physician-investigator and just a few patients to multinational, randomized trials intended to demonstrate superior clinical and economical outcomes with new device therapies in hundreds, sometimes thousands of patients. The BRC nowadays also hosts the Benelux Therapy & Procedure Training Center, where advanced simulator training is offered to physicians, nurses and technicians.