超声造影PPT

容积超声造影通过一系列的二维图像采集，捕捉流入脉管系统 的微气泡造影剂形成的非线性二次谐波信号。在体外流速模型 及体内正常/受损肾脏的动物研究中，收集来自时间-强度曲线 的组织灌注参数（峰强度、达峰值强度时间、內洗率、曲线下 面积）。
For the flow phantom studies, either the concentration of MB contrast agent was held constant (10 μL/L) with varying volumetric flow rates (10, 20, and 30 mL/min) or the flow rate was held constant (30 mL/min) and the contrast agent concentration was varied (5, 10, and 20 μL/L). 在体外流速模型研究中，保证微气泡浓度稳定（10 μL/L）， 改变容积流速率（10, 20, and 30 mL/min），或者保证流速稳定 （30 mL/min），改变微气泡浓度(5, 10, and 20 μL/L)。
Figure 1a shows time-intensity curves for three different MB concent rations for a fixed volumetric flow rate. All three time-intensity curve s reach their peak intensity at the same time point。 图1a显示固定容积流速，改变微泡造影剂浓度所形成的时间强度曲线。三条时间强度曲线均在同一时间达到了峰强度。 The derived perfusion parameters from time-intensity curve data (i.e., IPK,TPK, WIR, and AUC) are described in Figure 1a. 从时间强度曲线中可以得出IPK/TPK/WRI/AUC等灌注参数。
IPK revealed a linear relationship with the concentration of contrast ag ent used (Figure 2e, R2 = 0.56, P < 0.001), as did WIR (Figure2g, R2 = 0.75, P < 0.005) and AUC (Figure 2h, R2 = 0.93, P <0.001). TPK (F igure 2b, R2 =0.93, P < 0.001), WIR (Figure 2c, R2 = 0.92, P < 0.001) , and AUC (Figure 2d, R2 = 0.77, P <0.005) had linear relationships w ith changes in flow rate. there was also no significant change in TPK with respect to contrast concentration (Figure 2f, P > 0.85) as well as I PK with respect to flow speed (Figure 2a, P > 0.06).
图4提示灌注参数与接收器角度变化之间的关系。从图中可以看 出四个灌注参数与与传感器角度无统计学差异(P > 0.48)。
3. After induction of renal ischemia-reperfusion injury in a rat animal model (N = 4), VCEUS imaging of the injured kidney revealed an initial reduction in renal perfusion when compare d to control animals followed by a progressive recovery of va scular function. 3.建立老鼠肾脏缺血再灌注损害动物模型后，与持续血管 功能恢复的对照组动物模型组相比，受损肾脏的容积超 声造影图像显示肾脏灌注显著降低。
VCEUS could provide a more detailed idea of the actual percentage of ischemic tissue resulting from this renal complication by identifying regions of ischemic tissue.
三Results
1. Flow phantom results revealed a linear relationship between MB c oncentrations injected into the flow system and the IPK, WIR, and A UC perfusion measures (R2 > 0.56, P <0.005). Further, there was a li near relationship between changes in volume flow rate and the TPK, WIR, and AUC metrics (R2 > 0.77, P < 0.005). 1.血流模型结果提示注射入流速系统的微泡浓度与峰强度、內 洗率及曲线下面积呈线性相关（R2>0.56，P<0.005）。另外， 容积流率变化值与时间流速峰值、內洗率、曲线下面积度量值 呈线性相关(R2 > 0.77, P < 0.005)。
Volumetric contrast-enhanced ultrasound imaging of renal perfusion
肾灌注的容积超声造影显像
Байду номын сангаас 一 Objective
Volumetric contrast-enhanced ultrasound (VCEUS) ima ging has the potential to monitor changes in renal perfus ion following vascular injury.
Animal studies were performed using either healthy rats or those that underwent renal ischemia-reperfusion injury. A series of renal studies were performed using healthy rats (N = 4) while the angle of the transducer was varied for each VCEUS image acquisition (reference or 0°, 45°,and 90°) to assess if repeated renal perfusion measures were isotropic and independent of transducer position. Blood serum biomarkers and immunohistology were used to confirm acute kidney injury. 动物研究应用健康小鼠及遭受缺血再灌注的小鼠来完成。用正 常小鼠完成一系列肾脏研究，每次超声造影图像采集的传感器 角度是多变的（参考角度为0°、45°、90°），以便评估重 复的肾脏灌注方法是等向性的，其独立于传感器方位。血浆生 物标记物及免疫组织学用来确诊急性肾损害。
Figure 3 illustrates the time intensity curves obtained at different tran sducer orientations: 0°(origin), 45°, and 90°. Importantly, a stron g correlation was found between time intensity curves acquired at the various transducer scanning angles (ρ > 0.98, P < 0.001).
容积超声造影显像可以作为一种监测血管损伤后肾脏灌注变 化的潜在手段。
•
Current methods for quantifying AKI are searching for bio-markers i ndicative of kidney injury such as positive fluctuations in serum crea tinine .However, serum creatinine levels lack the sensitivity and speci ficity necessary for early detection . Due to the nephrotoxic nature of both CT and MR contrast agents, other standard perfusion imaging modalities are not suitable for diagnosis and monitoring of AKI. 目前确诊AKI的方法主要通过寻找血液中肾脏损害的生物标志物 ，例如血肌酐水平升高。但是血肌酐缺乏早期诊断的敏感性及 特异性。由于CT及MR造影本身存在肾毒性，而其他标准灌注显 像模式不适合诊断及监测AKI。
通过鉴别缺血组织区域，肾脏造影能够对由于肾脏并发症造成 的缺血组织的实际百分比提供更加细致的理念。
The focus of this paper is to investigate the repeatability and robustness of VCEUS imaging for tracking perfusion changes in the healthy and injured kidney.
这篇文章主要致力于观察超声造影显像追踪正常及受损肾脏灌 注变化的可重复性及稳定性。
二Method
VCEUS utilizes a series of planar image acquisitions, capturing the non-linear second harmonic signal from microbubble (MB) contrast agents flowing in the vasculature. Tissue perfusion parameters (peak intensity, IPK; time-to-peak intensity, TPK; wash-in rate, WIR; area under curve, AUC) were derived from time-intensity curve data coll ected during in vitro flow phantom studies and in vivo animal studie s of healthy and injured kidney.
2. No significant difference was found between the transducer angle during data acquisition and any of the derived renal perf usion measures (P >0.60). 2. 数据获取期间传感器角度与所有肾脏灌注参数之间无 显著性相关性(P >0.60)。
图3为传感器在0°、45°及90°三个不同角度所获得的时间强 度曲线。从图中可以看出不同传感器角度获得的时间强度曲线 存在显著相关性。
Figure 4 describes the perfusion parameters versus changes in image acquisition angle. There was no statistical difference between all thre e angles in any of the four parameters investigated (P > 0.48).