Photoacoustic venous blood pressure sensing: a feasibility study

Portal hypertension (PH) is defined as high blood pressure in the splanchnic venous system, which is the driver of life-threatening complications. Currently Hepatic Venous Pressure Gradient (HVPG) is the golden standard for diagnosis of PH, which is an invasive technique with procedural risks and complications and other limitations in clinical practice. Therefore, we proposed a new vein pressure detection method based on photoacoustic (PA) technology, providing non-invasive direct estimation of portal vein pressure. In the in vitro experiments, we simulated the blockage of human blood vessels by squeezing a silicone tube, detected the pressure in real time by a liquid pressure sensor, and analyzed the frequency-domain signals. The experimental results show that the larger the portal vein pressure is, the wider bandwidth the frequency domain signal has. This proposal is a promising solution to safe and convenient portal vein pressure detection.