Image-Free Technique for Flow Mediated Dilation Using ARTSENS® Pen

Flow mediated dilation (FMD) is a clinically accepted non-invasive tool for assessing endothelial dysfunction. FMD is conventionally performed with B-mode ultrasound systems that involve recording of the image sequences as DICOM files or video-graphic files and processing them offline. Sometimes the examinations may have to be rejected due to poor or unstable image sequences resulting non-reliable diameter estimates. We had earlier developed and extensively validated an image-free ultrasound technology, ARTSENS®, for the measurement of carotid artery wall dynamics and arterial stiffness metrics. In this work, we evaluate the feasibility of using the technology for continuous real-time diameter measurement of the brachial artery and thereby FMD. To investigate the performance of the ARTSENS® device an in-vivo study was conducted on 5 subjects as pilot. As a reference the measurements were also performed by a B-mode imaging system with a help of a commercially available clinically validated offline FMD analysis tool. The brachial artery diameter and FMD measurements performed by the ARTSENS® device were consistent with the earlier reported literature. The beat-to-beat repeatability of the baseline diameter measurements was acceptable with a CoV < 4% for all the subjects. The diameter measurements performed by the two devices exhibited a significant correlation (r-square = 0.81, p < 0.05). The RMSE for the diameter and FMD% measurements was 0.32 mm and 0.63% respectively, illustrating the measurement accuracy. The study demonstrated that the ARTSENS® can be reliably employed for performing FMD measurements and assessing endothelial dysfunction. This would help realize a field deployable solution for real-time automated FMD measurement and consequently for the acceleration of large population studies in this research area.