Postural Influences on Remote Measurements of Neck Pulsations: An Ultrasonographic Investigation
Laser Doppler vibrometers (LDV) and camera-based micro-motion imaging systems can sense neck pulsations. This allows carotid artery (CA) or jugular vein (JV) displacements to be acquired in a non-obtrusive and cost-effective way. However, neck-skin measurements are invalid if there are overlapping contributions from the CA and JV wall movements. The concern is plausible since these vessels are anatomically close to one another until the carotid bulb. In this paper we build on ultrasonographic insights to verify whether trunk posture (in particular the elevation of the neck relative to heart) influences the contribution of CA and JV pulsations to the skin-displacement signals. We hypothesize that the JV is occluded in the upright position, thus favoring CA measurements. Conversely, the JV is expected to be fully extended and a dominant source of neck pulsations in supine. We measured 4 subjects (ages, 26-32; 2 females) in the supine, recumbent and seated positions. Our results confirm the posture-dependency of neck surface measurements: CA displacements are best acquired in the upright-seated position, while JV displacements are indeed dominant in supine. Our insights help to ensure the validity of methods which explore remote neck pulsations.
- Postural Influences on Remote Measurements of Neck Pulsations: An Ultrasonographic Investigation
Andreia Moco, Paul Hamelmann, Sander Stuijk, and Gerard de Haan.
In Conference of the IEEE Engineering in Medicine and Biology Society, EMBC 18, Proceedings, pages xyz-xyz. Honololulu, USA, 17-21 July 2018. IEEE, 2018. (abstract, pdf, doi).