Single crystal ultrasound guided non-invasive assessment of jugular venous pressure

Objective: We have developed a handheld device for non-invasive quantitative assessment of jugular venous pressure (JVP). Methods: We used a single crystal ultrasound coupled to a force-sensing load cell to measure JVP based on the force necessary to collapse the internal jugular vein (IJV) walls. We used a gelatin-based model system of the IJV to test the ability of single crystal ultrasound to identify the IJV and verified the cross-sectional position and diameter of the vessels with conventional imaging ultrasound. We also tested our prototype device on healthy human volunteers. Results: Experiments on model system demonstrated that vessel diameters determined with single crystal ultrasound were in close agreement with the diameters derived from conventional two-dimensional ultrasound. Proof-of-concept human experiments demonstrate that single crystal ultrasound can detect the IJV in basal and collapsed states, as compared to gold-standard sonography. Assessment of JVP in human volunteers was physiologically consistent with and sensitive to postural changes (supine JVP 6.6 $\pm$ 2.4 mmHg; standing JVP 4.2 $\pm$ 1.9 mmHg (p<0.0001). Conclusion: Non-invasive assessment of JVP could prove valuable in informing rapid clinical decision-making across various pathologies and conditions leading to derangements in intravascular volume status.