这项工作部分得到了美国陆军医学研究材料司令部W81XWH-08-1-0503和W81XWH-12-1-0066的支持，AHA授予No0655441U和15SDG25740015以及NIH R21 HL081892，R21 HL130899，R21 HL089175，RC1 DK087365，R01 DK098526，R01 DK118964，R01 CA140338，R01 CA234428，Lantheus Medical Imaging和GE Healthcare，挪威奥斯陆。

托马斯杰斐逊大学和宾夕法尼亚大学医院的机构审查委员会批准了该协议。该协议符合《健康保险流通与责任法案》。美国食品和药物管理局（FDA）为该协议发布了研究性新药批准（IND # 124，465至F. Forsberg）。GE Healthcare（挪威奥斯陆）提供了本研究中使用的UCA（Sonazoid; 表 1）。Sonazoid未被FDA批准用于美国的任何临床应用，这就是为什么需要IND的原因。其他获得 FDA 批准1 的 UCA 如果认为有潜在的临床有用，可以由主治医生自行决定在标签外使用。
注意:完整的协议和统计分析计划可在 https:// clinicaltrials.gov/ct2/show/NCT02489045 获得。试验注册号:NCT # 02489045。
1. 科目准备
<ol><li>查看受试者已知的药物过敏或不耐受，特别是对正在使用的UCA的任何已知过敏。</li>
	<li>排除心肺疾病不稳定或通常医学不稳定的受试者。</li>
	<li>将受试者仰卧放在担架上。</li>
	<li>将 18 - 22 号套管放在受试者右臂或左臂的静脉中以进行 UCA 输注。</li>
	<li>确保医院内提供紧急服务（例如，急救车），以防出现任何急性不良反应。 注意:UCA非常安全，报告的严重类过敏反应发生率低于0.01%。20</li>
</ol>2. UCA制备（特定于声纳肽）
<ol><li>根据制造商的说明重悬，为每个受试者准备三 （3） 个装有 48 μL 微气泡 （6 mL） 的小瓶。UCA 以干粉形式提供，装在 10 mL 密封小瓶中。小瓶的顶部空间含有全氟丁烷。<ol><li>用化学尖刺穿UCA小瓶的塞子。</li>
		<li>从化学尖峰的注射器端口取下保护帽，并加入2mL无菌水。</li>
		<li>将注射器留在化疗尖峰上，立即摇动产品 1 分钟以确保产品均匀。</li>
		<li>将产品撤回注射器，然后再次将产品重新注入小瓶中。这是为了避免由于化学尖峰中的死区体积而导致产品稀释。</li>
		<li>从注射器端口取出注射器并重新安装保护盖。重组UCA的浓度为8 μL微泡/mL。</li>
		<li>对其他2个小瓶重复复溶程序。</li>
	</ol></li>
	<li>在连接到 3 通旋塞阀之前，使用生理盐水（0.9% NaCl 溶液）填充连接管。然后，旋塞阀将连接到通向套管的延长管。</li>
	<li>将所有三 （3） 瓶悬浮的 UCA 抽入 10 mL 注射器中，并将其放入患者相同水平或下方的注射泵中，并直接连接到旋塞阀。</li>
	<li>在初始超声成像和旋塞阀打开后，以 120 mL/h 的速度输注 NaCl 溶液，并以每公斤体重每分钟 0.024 μL 的速率共同输注 Sonazoid（悬浮输注速率为 0.18 mL/kg/小时）。 注意:该输注速率是根据我们小组以前在接受SHAPE13，14，21的门静脉高压受试者中输注声纳样的经验选择的。确切的重悬程序和输液方法将根据所使用的UCA而有所不同。</li>
</ol>3. 初始超声成像
<ol><li>打开超声扫描仪（例如 Logiq E10 版本 R2）的电源并选择 C1-6-D 曲线探头。</li>
	<li>在超声扫描仪上选择一个腹部预设，并使用曲线阵列（通常具有1-6或2-8 MHz带宽）在同一成像平面和相似深度获取门静脉和肝静脉的灰度图像（图1）。这通常最好通过肋下方法来实现。</li>
	<li>根据良好临床实践优化图像，并注意选择远离下腔静脉的肝静脉区域，以避免逆行血流的影响。</li>
</ol>4. SHI 和形状成像
<ol><li>使用 次谐波对比度 触摸屏按钮在双显示模式下激活 SHI 对比度成像模式（即同时运行实时 B 模式和 SHI），并激活对比度模式。然后在旋转控制器上选择 SUBH-AM 。<ol><li>以 2.5 MHz 的发射频率执行 SHI，并在 1.25 MHz 处获得接收信号。</li>
		<li>使用脉冲整形来最大限度地产生次谐波微气泡信号，例如带有声纳样的高斯窗口二项式滤波方波，21 但这依赖于扫描仪和 UCA。17 注:最终用户可能无法选择成像频率和脉冲形状。</li>
	</ol></li>
	<li>确认门静脉和肝静脉的通畅性以及微气泡的存在，从输注开始可能需要长达1-2分钟。</li>
	<li>激活 SHAPE 自动优化代码，通过补偿不同的深度和衰减来优化 SHAPE。22，23 在触摸屏上选择 TIC 分析，然后选择 F6，然后选择 k 按钮。</li>
	<li>SHAPE优化算法将获取每个声学输出电平的次谐波数据。数据采集完成后，在对比样本窗口（TIC分析屏幕左上角）的门静脉上放置ROI。<ol><li>将ROI内的平均次谐波数据绘制为声学输出的函数，并将逻辑曲线拟合到数据。选择该曲线的拐点（或者更确切地说是下面显示的导数曲线中的峰值）作为优化功率，因为这已被证明是SHAPE灵敏度最高的点。22，23 图2显示了一组这样的曲线。</li>
	</ol></li>
	<li>将声学输出功率调整到步骤4.4.1中确定的值，这将确保次谐波幅度的最大变化是环境压力的函数（即，最大化SHAPE的灵敏度）。</li>
	<li>在输注UCA悬浮液期间，从5-15秒段的微气泡（即SHAPE）获取次谐波数据（图3）。</li>
</ol>5. 形状数据处理
<ol><li>获取优化的SHI电影循环（步骤5.6）后，在触摸屏上选择"TIC分析"。<ol><li>确保触摸面板上的"运动跟踪"已激活，该面板会调整每帧的ROI位置以补偿任何呼吸或其他运动。</li>
		<li>确保在分析窗口中选择dB作为迹线上Y轴的单位。</li>
	</ol></li>
	<li>在对比样本窗口（屏幕左上角）中，选择肝静脉和门静脉内相同的ROI（椭圆区域为默认）。在分析窗口（右侧）中，每个容器内的次谐波信号（以dB为单位）在1.25 MHz左右的0.5 MHz带宽内的所有帧上平均。</li>
	<li>计算最终的SHAPE梯度（以dB为单位）作为肝静脉和门静脉ROI之间平均次谐波信号的差异。根据目前的研究，识别CSPH的最佳工作点为-0.11 dB，线性回归方程为HVPG = 0.81 x SHAPE + 9.43。14 需要注意的是，这个截止值和方程都取决于扫描仪和UCA。</li>
</ol>

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Forsberg，Gupta，Wallace和Eisenbrey博士正在申请SHAPE技术的专利。华莱士博士是通用电气的员工。

长期以来，无创、准确测量人体内压力一直是一个重要但难以捉摸的临床目标。这里介绍的SHAPE测量协议实现了这一目标。SHAPE程序最关键的组成部分是优化算法，因为在最佳声功率输出下未获得的次谐波数据与静水压力的相关性较差。17，22，23 在Logiq 9扫描仪上实现的该软件的初始版本容易在S曲线的导数中显示多个峰值（参?...

许多不同的超声造影剂（UCA）被批准用于心脏病学（特别是左心室混浊）和放射学（特别是成人和儿童肝脏病变特征）的临床应用。1 超声成像的灵敏度和特异性可以通过静脉内 （IV） 注射由脂质或蛋白质外壳封装的充满气体的微气泡（直径 < 10 μm）作为 UCA 来提高，UCA 穿过整个脉管系统并将信号增强高达 30 dB。1 这些UCA不仅增强了反向散射超声信号，而且在足够的声压（>200 kPa）下，它们还充当非线性振荡器。因此，在接收到的回波中将产生重要的能量成分，范围从次谐波和谐波到超谐波频率。1，2 这些非线性信号分量可以从组织和线性气泡回波中提取（例如，使用脉冲反转），并用于创建对比特定的成像模式，例如次谐波成像（SHI），其接收频率为发射频率的一半（即f 0/2）。3 我们小组在人体临床试验中证明，SHI可以检测与各种肿瘤和组织相关的新血管和小动脉中的血流。4，5，6，7，8，9
我们提倡不使用UCA作为血管示踪剂，而是通过监测次谐波对比气泡振幅变化来作为循环系统中无创压力估计的传感器。10这种称为次谐波辅助压力估计（SHAPE）的创新技术依赖于大多数商业UCA在体外测量的次谐波信号幅度与静水压力（高达186 mmHg）之间的反线性相关性（r2>0.90），如表1所示。10，11 但是，应该注意的是，并非所有 UCA 都表现出这种行为。最值得注意的是，已经表明，来自UCA SonoVue（在美国称为Lumason）的次谐波信号最初随着静水压力的增加而上升，然后是平台期和下降阶段。12尽管如此，SHAPE提供了允许无创获得心脏和整个心血管系统的压力梯度以及肿瘤中的间质液压力的可能性。13，14，15，16，17 最近，我们在商用超声扫描仪上实现了SHAPE算法的实时版本，并提供了概念验证，即SHAPE可以提供体内压力估计，患者的左心室和右心室误差小于3 mmHg。16，17 
迄今为止，SHAPE的最多经验是诊断门静脉高压症，入组了220多名受试者，并在一项多中心试验中证实了初步发现。13，14 门静脉高压定义为门静脉与肝静脉或下腔静脉之间的压力梯度增加超过 5 mmHg，而临床上显着的门静脉高压 （CSPH） 需要梯度或等效值，肝静脉压梯度 （HVPG） ≥ 10 mmHg。18 CSPH 与胃食管静脉曲张、腹水、肝失代偿、术后失代偿和肝细胞癌的风险增加有关。18，19 发生腹水的患者三年死亡率为 50%，发生腹水自发感染的患者一年死亡率为 70%。肝硬化患者胃食管静脉曲张形成年发病率为5-10%，出血年发生率为4-15%;每次出血发作都有高达20%的死亡风险。18，19 
本手稿描述了如何使用市售设备和UCA进行SHAPE研究，重点是识别患者肝脏中的门静脉高压症。详细解释了实现估算压力变化的最高灵敏度所需的关键校准程序。

<table><tbody><tr><td>2 mL syringe</td><td>Becton Dickinson</td><td>309637</td><td>Used for reconstituting Sonazoid</td></tr><tr><td>10 mL saline-filled syringe</td><td>Becton Dickinson</td><td>306545</td><td>Used for flushing line to verify IV access</td></tr><tr><td>500 mL saline bag</td><td>Baxter Healthcare Corp</td><td>2131323</td><td>Used for co-infusion with Sonazoid</td></tr><tr><td>C1-6-D curvi-linear proble</td><td>GE Healthcare</td><td>H40472LT</td><td>Used for liver imaging</td></tr><tr><td>Chemoprotect Spike</td><td>Codan USA</td><td>C355</td><td>Chemospike used for reconstituting Sonazoid</td></tr><tr><td>Discofix C Blue</td><td>B. Braun Medical Inc</td><td>16494C</td><td>3-way stopcock</td></tr><tr><td>Intrafix Safeset 180 cm</td><td>B. Braun Medical Inc</td><td>4063000</td><td>Infusion tubing</td></tr><tr><td>Logiq E10 ultrasound scanner</td><td>GE Healthcare</td><td>H4928US</td><td>Used for conventional ultrasound imaging as well as for SHI and SHAPE</td></tr><tr><td>Luer lock 10 mL syringe</td><td>Becton Dickinson</td><td>300912</td><td>For infusion of Sonazoid</td></tr><tr><td>Medfusion 3500 syringe pump</td><td>Smiths Medical</td><td>3500-500</td><td>Used for infusing Sonazoid at 0.18 mL/kg/hour</td></tr><tr><td>Perfusor-leitung tubing 150 mm</td><td>B. Braun Medical Inc</td><td>8722960</td><td>Extension line enabling syringe connection to patient&#039;s IV access</td></tr><tr><td>SHI/SHAPE software</td><td>GE Healthcare</td><td>H4920CI</td><td>Contrast-specific imaging software</td></tr><tr><td>Sigma Spectrum infusion system</td><td>Baxter Healthcare Corp</td><td>35700BAX</td><td>Pump used for co-infusing saline at 120 mL/hour</td></tr><tr><td>Sonazoid</td><td>GE Healthcare</td><td></td><td>Gas-filled microbubble based ultrasound contrast agent</td></tr><tr><td>sterile water, 2 mL</td><td>B. Braun Medical Inc</td><td></td><td>Used for reconstituting Sonazoid</td></tr><tr><td>ultrasound gel</td><td>Cardinal Health</td><td>USG-250BT</td><td>Used for contact between probe and patient</td></tr><tr><td>Venflon IV cannula 22GA</td><td>Becton Dickinson</td><td>393202</td><td>Cannula needle for obtaining IV access</td></tr></tbody></table>

contrast-enhanced subharmonic aided pressure estimation (shape) using ultrasound imaging with a focus on identifying portal hypertension

长期以来，无创、准确测量人体内压力一直是一个重要但难以捉摸的临床目标。用于超声成像的造影剂是充满气体的封装微气泡（直径< 10 μm），可穿过整个脉管系统并将信号增强多达 30 dB。这些微气泡还产生非线性振荡，频率范围从次谐波（发射频率的一半）到更高次谐波。次谐波幅度与环境静水压力呈反比线性关系。这里介绍了一种能够执行实时次谐波辅助压力估计（SHAPE）的超声系统。在超声造影剂输注期间，激活了优化声学输出的算法。在此校准之后，次谐波微气泡信号（即SHAPE）对压力变化具有最高的灵敏度，可用于无创量化压力。SHAPE程序在识别肝脏门静脉高压症方面的效用是这里的重点，但该技术在许多临床场景中具有适用性。

与所有超声影像学检查一样，肝脏 SHAPE 的首要考虑因素是获得目标区域的最佳基线灰度图像，并确保（使用多普勒成像）不存在肝内门静脉分流或其他血管异常。在用于诊断门静脉高压的肝脏成像的情况下，关键是在同一深度上可视化门静脉和肝静脉，以尽量减少衰减的影响（图1）。
尽管UCA浓度不被认为是SHAPE程序10，23...

Watch this Scientific Journal Video about Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension at JoVE.com

Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

通过人类慢性肝病患者的例子描述了利用注入对比微泡的次谐波超声成像（经过适当校准）无创估计环境压力的方案。

使用超声成像的对比增强次谐波辅助压力估计 （SHAPE），重点是识别门静脉高压症

Noninvasive, accurate measurement of pressures within the human body has long been an important but elusive clinical goal. Contrast agents for ultrasound ...

contrast-enhanced-subharmonic-aided-pressure-estimation-shape-using

Universidad de Cartagena UDEC

Research

JoVE Journal

Bioengineering

Contrast-Enhanced Subharmonic Aided Pressure Estimation (SHAPE) Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

2.2K 次观看.  Thomas Jefferson University. 通过人类慢性肝病患者的例子描述了利用注入对比微泡的次谐波超声成像（经过适当校准）无创估计环境压力的方案。

视频: Contrast-Enhanced Subharmonic Aided Pressure Estimation SHAPE Using Ultrasound Imaging with a Focus on Identifying Portal Hypertension

Real-time Monitoring of High Intensity Focused Ultrasound (HIFU) Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound (HMIFU)

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An oscillatory motion is generated at the focus of a 93-element and 4.5 MHz center frequency HIFU transducer by applying a 25 Hz amplitude-modulated signal using a function generator. A 64-element and 2.5 MHz imaging transducer with 68kPa peak pressure is confocally placed at the center of the HIFU transducer to acquire the radio-frequency (RF) channel data. In this protocol, real-time monitoring of thermal ablation using HIFU with an acoustic power of 7 W on canine livers in vitro is described. HIFU treatment is applied on the tissue during 2 min and the ablated region is imaged in real-time using diverging or plane wave imaging up to 1,000 frames/second. The matrix of RF channel data is multiplied by a sparse matrix for image reconstruction. The reconstructed field of view is of 90&#176; for diverging wave and 20 mm for plane wave imaging and the data are sampled at 80 MHz. The reconstruction is performed on a Graphical Processing Unit (GPU) in order to image in real-time at a 4.5 display frame rate. 1-D normalized cross-correlation of the reconstructed RF data is used to estimate axial displacements in the focal region. The magnitude of the peak-to-peak displacement at the focal depth decreases during the thermal ablation which denotes stiffening of the tissue due to the formation of a lesion. The displacement signal-to-noise ratio (SNRd) at the focal area for plane wave was 1.4 times higher than for diverging wave showing that plane wave imaging appears to produce better displacement maps quality for HMIFU than diverging wave imaging.

Real-time Monitoring of High Intensity Focused Ultrasound HIFU Ablation of In Vitro Canine Livers Using Harmonic Motion Imaging for Focused Ultrasound HMIFU

This article describes real-time monitoring of HIFU ablation in canine liver with high frame rate ultrasound imaging using diverging and plane wave imaging. Harmonic Motion Imaging for Focused Ultrasound is used to image the decrease of acoustic radiation force induced displacement in the ablated region.

高强度的实时监控聚焦超声（HIFU）消融<em&gt;体外</em&gt;使用谐运动成像的聚焦超声犬肝脏（HMIFU）

Harmonic Motion Imaging for Focused Ultrasound (HMIFU) is a technique that can perform and monitor high-intensity focused ultrasound (HIFU) ablation. An ...

科研

生物工程

Manufacturing Abdominal Aorta Hydrogel Tissue-Mimicking Phantoms for Ultrasound Elastography Validation

Ultrasound (US) elastography, or elasticity imaging, is an adjunct imaging technique that utilizes sequential US images of soft tissues to measure the tissue motion and infer or quantify the underlying biomechanical characteristics. For abdominal aortic aneurysms (AAA), biomechanical properties such as changes in the tissue's elastic modulus and estimates of the tissue stress may be essential for assessing the need for the surgical intervention. Abdominal aortic aneurysms US elastography could be a useful tool to monitor AAA progression and identify changes in biomechanical properties characteristic of high-risk patients.
A preliminary goal in the development of an AAA US elastography technique is the validation of the method using a physically relevant model with known material properties. Here we present a process for the production of AAA tissue-mimicking phantoms with physically relevant geometries and spatially modulated material properties. These tissue phantoms aim to mimic the US properties, material modulus, and geometry of the abdominal aortic aneurysms. Tissue phantoms are made using a polyvinyl alcohol cryogel (PVA-c) and molded using 3D printed parts created using computer aided design (CAD) software. The modulus of the phantoms is controlled by altering the concentration of PVA-c and by changing the number of freeze-thaw cycles used to polymerize the cryogel. The AAA phantoms are connected to a hemodynamic pump, designed to deform the phantoms with the physiologic cyclic pressure and flows. Ultra sound image sequences of the deforming phantoms allowed for the spatial calculation of the pressure normalized strain and the identification of mechanical properties of the vessel wall. Representative results of the pressure normalized strain are presented.

Here we describe a method to manufacture aneurysmal, aortic tissue-mimicking phantoms for the use in testing ultrasound elastography. The combined use of computer-aided design (CAD) and 3-dimensional (3D) printing techniques produce aortic phantoms with predictable, complex geometries to validate the elastographic imaging algorithms with controlled experiments.

超声弹性成像验证腹主动脉水凝胶组织模拟幻影的研制

Ultrasound (US) elastography, or elasticity imaging, is an adjunct imaging technique that utilizes sequential US images of soft tissues to measure the ...

Invasive Hemodynamic Characterization of the Portal-hypertensive Syndrome in Cirrhotic Rats

This is a detailed protocol describing invasive hemodynamic measurements in cirrhotic rats for the characterization of portal hypertensive syndrome. Portal hypertension (PHT) due to cirrhosis is responsible for the most severe complications in patients with liver disease. The full picture of the portal hypertensive syndrome is characterized by increased portal pressure (PP) due to the increased intrahepatic vascular resistance (IHVR), hyperdynamic circulation, and increased splanchnic blood flow. Progressive splanchnic arterial vasodilation and increased cardiac output with elevated heart rate (HR) but low arterial pressure characterizes the portal hypertensive syndrome.
Novel therapies are currently being developed that aim to decrease PP by either targeting IHVR or increased splanchnic blood flow &#8212; but side effects on systemic hemodynamics may occur. Thus, a detailed characterization of portal venous, splanchnic, and systemic hemodynamic parameters, including measurement of PP, portal venous blood flow (PVBF), mesenteric arterial blood flow, mean arterial pressure (MAP), and HR is needed for preclinical evaluation of the efficacy of novel treatments for PHT. Our video article provides the reader with a structured protocol for performing invasive hemodynamic measurements in cirrhotic rats. In particular, we describe the catheterization of the femoral artery and the portal vein via an ileocolic vein and the measurement of portal venous and splanchnic blood flow via perivascular Doppler-ultrasound flow probes. Representative results of different rat models of PHT are shown.

Here we describe a detailed protocol for invasive measurements of hemodynamic parameters including portal pressure, splanchnic blood flow, and systemic hemodynamics in order to characterize the portal hypertensive syndrome in rats.

肝硬化大鼠门脉高压综合征的侵袭性血流动力学特征

This is a detailed protocol describing invasive hemodynamic measurements in cirrhotic rats for the characterization of portal hypertensive syndrome. ...

医学

Measurement of the Hepatic Venous Pressure Gradient and Transjugular Liver Biopsy

Here we provide a detailed protocol describing the clinical procedure of hepatic venous pressure gradient (HVPG) measurement in patients with advanced chronic liver disease followed by an instruction for transjugular biopsy. Under local anesthesia and ultrasound guidance, a catheter introducer sheath is placed in the right internal jugular vein. Using&#160;fluoroscopic guidance, a balloon catheter is advanced into the inferior vena cava (IVC) and inserted into a large hepatic vein. Correct and sufficient wedge position of the catheter is ensured by injecting contrast media while the balloon is blocking the outflow of the cannulated hepatic vein. After calibrating the external pressure transducer, continuous pressure recordings are obtained with triplicate recordings of the wedged hepatic venous pressure (WHVP) and free hepatic venous pressure (FHVP). The difference between FHVP and WHVP is referred to as HVPG, with values &#8805;10 mm Hg indicating clinically significant portal hypertension (CSPH). Before removing the catheter, pressure readings obtained in the IVC at the same level, as well as the right atrial pressure are recorded.
Finally, a transjugular liver biopsy can be obtained via the same vascular route. Different systems are available; however, core biopsy needles are preferred over aspiration needles, especially for cirrhotic livers. Again, under fluoroscopic guidance a biopsy needle introducer sheath is advanced into an hepatic vein. Next, the transjugular biopsy needle is gently advanced through the introducer sheath: (i) in case of aspiration biopsy, the needle is advanced into the liver parenchyma under aspiration and then removed quickly, or (ii) in case of a core biopsy, the cutting-mechanism is triggered inside the parenchyma. Several separate passages can be safely performed to obtain sufficient liver specimens via transjugular biopsy. In experienced hands, the combination of these procedures takes about 30-45 min.

Here, we present a protocol for measurement of hepatic venous pressure gradient (HVPG),the gold standard to diagnose clinically significant portal hypertension. Moreover, we describe how to perform a transjugular liver biopsy within the same session.

肝静脉压梯度和转性肝活检测量

Here we provide a detailed protocol describing the clinical procedure of hepatic venous pressure gradient (HVPG) measurement in patients with advanced ...

Point-of-Care Ultrasound: A Review of Ultrasound Parameters for Predicting Difficult Airways

Airway management remains a crucial part of perioperative care. The conventional approach to assessing potentially difficult airways emphasizes the LEMON method, which looks for and evaluates the Mallampati classification, signs of obstruction, and neck mobility. Clinical findings help predict a higher likelihood of difficult tracheal intubation, but no clinical result reliably excludes difficult intubation. Ultrasound as an adjunct to clinical examination can provide the clinician with a dynamic anatomical airway assessment, which is impossible with clinical examination alone. In the hands of anesthesiologists, ultrasound is becoming more popular in the perioperative period. This method is particularly applicable for identifying proper endotracheal tube positioning in specific patient populations, such as those who are morbidly obese and patients with head and neck cancer or trauma. The focus is on identifying the normal anatomy, correctly positioning the endotracheal tube, and refining the parameters that predict difficult intubation. Several ultrasound measurements are clinical indicators of difficult direct laryngoscopy in the literature. A meta-analysis revealed that the distance from the skin to the epiglottis (DSE) is most associated with a difficult laryngoscopy. An ultrasound of the airway could be applied in routine practice as an adjunct to the clinical examination. A full stomach, rapid sequence intubation, gross visual anatomical abnormalities, and restricted neck flexibility prevent using ultrasound to assess the airway. The airway evaluation is performed with a linear array transducer of 12-4 MHz, with the patient in the supine position, with no pillow, and with the head and neck in a neutral position. The central axis of the neck is where the ultrasound parameters are measured. These image acquisitions guide the standard ultrasound examination of the airway.

A point-of-care ultrasound (POCUS) is a simple, non-invasive, and portable tool that enables dynamic airway assessment. Several studies have attempted to determine the role of ultrasound parameters as an adjunct to clinical examination in predicting difficult laryngoscopies.

床旁超声:预测困难气道的超声参数综述

Airway management remains a crucial part of perioperative care. The conventional approach to assessing potentially difficult airways emphasizes the LEMON ...

使用床旁超声对腹主动脉进行成像

An Approach to Point-Of-Care Ultrasound Evaluation of the Abdominal Aorta

Disorders of the abdominal aorta, including aneurysms and dissection, have potentially high rates of morbidity and mortality. While computed tomography (CT) is the current gold standard to image the abdominal aorta, the process of obtaining a CT may be time-consuming, requires the use of intravenous contrast dye, and involves exposure to ionizing radiation. Point-of-care Ultrasound (POCUS) can be performed at the bedside and has excellent sensitivity and specificity for the diagnosis of abdominal aortic aneurysm and excellent specificity for the diagnosis of abdominal aortic dissection. Additionally, POCUS is non-invasive, cost-effective, lacks ionizing radiation, requires no intravenous contrast dye, and can be performed without taking the patient from a critical care area. Screening for abdominal aortic aneurysm (AAA) can be done in primary care settings as well. 
This article will review the approach to POCUS of the abdominal aorta to evaluate such critical pathology. In this paper, we will review the sonographic anatomy of the abdominal aorta as well as the choice of the ultrasound probe, description of POCUS image acquisition, and some pearls and pitfalls of using POCUS to aid in the diagnosis of potentially life-threatening abdominal aortic pathology.

作者聚焦：使用床旁超声全面评估腹主动脉

This protocol reviews the steps to image the abdominal aorta with point-of-care ultrasound. We discuss image acquisition, troubleshooting imaging pitfalls and artifacts, and the recognition of life-threatening abdominal aortic pathology.

腹主动脉床旁超声评估方法

Disorders of the abdominal aorta, including aneurysms and dissection, have potentially high rates of morbidity and mortality. While computed tomography ...

胃超声技术减轻围手术期误吸风险

Gastric Point of Care Ultrasound in Adults: Image Acquisition and Interpretation

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical inquiries related to gastric content. One emerging concern pertains to patients about to undergo sedation and/or endotracheal intubation: the elevated risk of aspiration from the patient&#39;s stomach contents. Aspiration of gastric contents into the lungs poses a serious and potentially life-threatening complication. This occurs more frequently when the stomach is considered &#34;full&#34; and can be affected by the techniques employed for airway management, making it potentially preventable. To mitigate the risk of peri-procedural aspiration, two distinct medical specialties (anesthesiology and critical care medicine) have independently developed techniques to utilize ultrasonography for identifying patients requiring &#34;full stomach&#34; precautions. Due to these separate specialties, the work of each group remains relatively unfamiliar outside its respective field. This article presents descriptions of both techniques for gastric ultrasound. Furthermore, it explains how these approaches can complement each other when one of them falls short. Regarding image acquisition, the article covers the following topics: indications and contraindications, selection of the appropriate probe, patient positioning, and troubleshooting. The article also delves into image interpretation, complete with example images. Additionally, it demonstrates how one of the two techniques can be employed to estimate gastric fluid volume. Lastly, the article briefly discusses medical decision-making based on the findings of this examination.

作者聚焦：用于围手术期护理中胃内容物评估和风险分层的床旁超声 

This protocol introduces two methods for image acquisition in gastric ultrasonography. Additionally, tips are provided for interpreting this information to assist in medical decision-making.

成人胃旁超声：图像采集和解释

Over the past two decades, diagnostic point-of-care ultrasound (POCUS) has emerged as a rapid and non-invasive bedside tool for addressing clinical ...

使用超声成像的对比增强次谐波辅助压力估计（SHAPE），重点是识别门静脉高压症

摘要

探索更多视频

此视频中的章节

高强度的实时监控聚焦超声（HIFU）消融

超声弹性成像验证腹主动脉水凝胶组织模拟幻影的研制

肝硬化大鼠门脉高压综合征的侵袭性血流动力学特征

肝静脉压梯度和转性肝活检测量

床旁超声:预测困难气道的超声参数综述

腹主动脉床旁超声评估方法

腹主动脉床旁超声评估方法

腹主动脉床旁超声评估方法

成人胃旁超声：图像采集和解释

成人胃旁超声：图像采集和解释

使用超声成像的对比增强次谐波辅助压力估计 （SHAPE），重点是识别门静脉高压症

摘要

探索更多视频

此视频中的章节

高强度的实时监控聚焦超声（HIFU）消融

超声弹性成像验证腹主动脉水凝胶组织模拟幻影的研制

肝硬化大鼠门脉高压综合征的侵袭性血流动力学特征

肝静脉压梯度和转性肝活检测量

床旁超声:预测困难气道的超声参数综述

腹主动脉床旁超声评估方法

腹主动脉床旁超声评估方法

腹主动脉床旁超声评估方法

成人胃旁超声：图像采集和解释

成人胃旁超声：图像采集和解释

使用超声成像的对比增强次谐波辅助压力估计（SHAPE），重点是识别门静脉高压症