Imec and Ghent University have developed a unique photonic-based medical device for the screening of arterial stiffness and the diagnosis of cardiovascular diseases. The brainchild of researchers from imec and Ghent University, the low-cost and portable device was made a reality by medical tech company Medtronic and partners from CARDIS (a Horizon 2020 project). The device has already undergone a clinical feasibility study in 100 patients and is set to revolutionize cardiovascular disease diagnosis.
Cardiovascular disease (CVD) is one of the leading global causes of mortality, and early identification of at-risk individuals can mean the difference between life and death. One of the recommended measures for CVD risk prediction, and a key marker for hypertension, is the assessment of arterial stiffness.
Arterial stiffness is determined by measuring the aortic pulse wave velocity (aPWV), the speed at which the blood pressure pulse from each heart beat moves through the body. Though there are a few different non-invasive techniques available to measure a patient’s aPWV, current devices are all either large, expensive, or difficult to operate, and tend only to be found in hospitals.
The laser device is not only cheap and easy to use, but it is also portable enough to be distributed to and used in a local doctor’s office. This means far more patient arterial stiffness screenings can be done once this device is widely distributed, as more people will have access to it. The imec device will enable the diagnosis of far more people at risk of CVD, saving both lives and healthcare costs.
Imec's new medical device for measuring arterial stiffness. Photo courtesy of imec.
How does it work?
The device operates using Laser Doppler Vibrometry (LDV), a low-power laser that is aimed at the skin overlying an artery. The skin’s vibration amplitude and frequency, results of the heart beat, are extracted from the reflected beam. The device includes two rows of six beams, meaning it scans multiple points on the skin above the artery in parallel.
At the heart of the device is a silicon photonics chip, special as it enables the small size of the device. This chip was designed by the Photonics Research Group, an imec laboratory at Ghent University, and then implemented using advanced optical packaging approaches developed at the Tyndall National Institute in Ireland. The whole system was then integrated into a handheld device, no larger than a common hair-dryer, and validated for human use by Medtronic.
From the bench to the doctor’s office
A clinical feasibility study with 100 patients has already been successfully completed by INSERM at the Georges Pompidou European Hospital in Paris, France. As the device is so mobile, low-cost, and allows for point-of-care screening with simple training, it has been gladly endorsed by doctors. Because the device only uses light, with minimal physical contact, patients have also reported huge satisfaction with the imec device.
“The CARDIS device was well accepted by all patients, and it was considered useful and well tolerated,” stated Dr. Pierre Boutouyrie, the cardiologist in charge of the feasibility study. “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), added: “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.”
Further clinical feasibility studies are now planned in the Academic Hospital of Maastricht (The Netherlands), where the next step is to produce a small series of the device to perform a study on a larger group of patients and over a longer period of time. If this feasibility study reinforces the technology’s ability to detect cardiovascular diseases at an early stage, high-volume production of the device can be initiated. Once the device is made available to doctors, many lives will be able to be saved by early CVD diagnosis and intervention.