Remote Intravascular Pressure Sensing using Ultrasound

项目摘要 肝硬化的许多临床上显著的并发症是由于门脉高压引起的。 高血压直接测量门静脉压力是有创的，需要大量的手术操作。 体验.因此，准确、无创的门静脉压力测量方法具有重要的临床应用价值。 降低风险并使临床医生能够改善肝病患者的常规检查的潜力。与 最后，我们的小组有令人兴奋的数据表明，组织中的远程压力传感可以使用 我们称之为组织血管内压力估计的新型造影剂和定制技术， 超声（TIPE-US）。最近的进展是相变造影剂（PCCA）的开发， 其在环境条件下是稳定的液体纳米液滴， 超声能量经历相变成为使用超声可检测的高回声微泡 显像我们小组的几项研究一致表明，PCCA所需的超声能量 激活是高度线性的并且取决于周围流体的流体静压。所以我们 假设这些PCCA和实时超声成像技术可用于远程血管内 压力传感和门静脉高压检测。拟议研究项目的总体目标是 开发下一代TIPE-US成像系统和方法，用于血管化患者的远程压力传感， 组织.该项目的第一个目标是实现新的TIPE-US功能和反馈控制， 可编程超声波扫描仪在第二个目标，我们将评估使用定制和单分散 在TIPE-US成像期间，PCCA可最大限度地提高感知信号生成和量化。我们还将进行 使用已建立的门静脉高压动物模型进行TIPE-US的首次体内试验。

PROJECT SUMMARY Many of the clinically significant complications of liver cirrhosis arise as a consequence of increased portal hypertension. Direct measurement of portal venous pressures is invasive and requires significant procedural experience. Therefore, an accurate and noninvasive method for measurement of portal venous pressure has the potential to reduce risk and enable clinicians to improve the routine workup of patients with liver disease. To that end, our group has exciting data that suggests remote pressure sensing in tissue can be performed using a novel contrast agent and custom technology we have termed tissue intravascular pressure estimation using ultrasound (TIPE-US). A recent advance was in the development of a phase-change contrast agent (PCCA), which is a stabilized liquid nanodroplet under ambient conditions but can be selectively activated using pulsed ultrasound energy to undergo a phase transition into a highly echogenic microbubble detectable using ultrasound imaging. Several studies by our group have consistently shown that the ultrasound energy required for PCCA activation is highly linear and dependent on the hydrostatic pressure of the surrounding fluid. Therefore, we hypothesize that these PCCAs and real-time ultrasound imaging techniques can be used for remote intravascular pressure sensing and detection of portal hypertension. The overarching goal of the proposed research project is to develop a next-generation TIPE-US imaging system and method for remote pressure sensing in vascularized tissue. The first aim of this project is to implement new TIPE-US functionality and feedback control on a programmable ultrasound scanner. In the second aim, we will evaluate the use of custom and monodisperse PCCAs to maximize sensing signal generation and quantification during TIPE-US imaging. We will also conduct the first in vivo tests of TIPE-US using an established animal model portal hypertension.