In vivo perfusion estimation using subharmonic contrast microbubble signals
In vivo perfusion estimation using subharmonic contrast microbubble signals
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DOI：
10.7863/jum.2006.25.1.15
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发表时间：
2006-01-01
影响因子：
2.3
通讯作者：
Hall, AL
中科院分区：
文献类型：
--
作者：
Forsberg, F;Liu, JB;Hall, AL
Objective.本研究的目的是使用对比增强次谐波成像（SHI）在体内定量灌注。方法.使用在灰度SHI模式下操作的改进的LOGIQ 9扫描仪（GE Healthcare，密尔沃基，WI）来测量体内SHI时间-强度曲线。4只犬接受静脉造影剂推注（剂量，0.1 mL/kg），并进行肾脏SHI。注射3次造影剂后，使用基于稳定（非放射性）同位素标记微球（BioPhysics Assay Laboratory Inc，Worcester，MA）的微血管染色技术定量每个肾脏8个切片中的灌注程度。通过结扎手术暴露的节段性肾动脉，然后注射造影剂和微血管染色诱导低灌注状态。将数字剪辑转移到个人计算机中，并使用Image-Pro Plus软件（Media Cybernetics，银Spring，MD）在每个切片中获取SHI时间-强度曲线。计算亚谐波分数血容量，并根据3次注射平均的分数血容量摄取的初始斜率估计灌注。使用线性回归分析将亚谐波灌注数据与金标准（即微球）进行比较。结果体内灰阶SHI清楚地显示了血流，因此，肾脏中的灌注几乎完全抑制了组织信号。总共获得270条SHI时间-强度曲线，平均后减少到94个灌注估计值。次谐波灌注估计值与微球结果显著相关（r = 0.57; P < .0001）。最佳SHI灌注估计值出现在肾脏前部的高灌注状态（r = 0.731; P=.0001）。相应的均方根误差为2.4%。结论.已在体内获得了次谐波灌注估计。灌注估计值与微血管染色技术的一致性良好。
Objective. The purpose of this study was to quantify perfusion in vivo using contrast-enhanced subharmonic imaging (SHI). Methods. A modified LOGIQ 9 scanner (GE Healthcare, Milwaukee, WI) operating in gray scale SHI mode was used to measure SHI time-intensity curves in vivo. Four dogs received intravenous contrast bolus injections (dose, 0.1 mL/kg), and renal SHI was performed. After 3 contrast agent injections, a microvascular staining technique based on stable (nonradioactive) isotope-labeled microspheres (BioPhysics Assay Laboratory Inc, Worcester, MA) was used to quantify the degree of perfusion in 8 sections of each kidney Low perfusion states were induced by ligating surgically exposed segmental renal arteries followed by contrast agent injections and microvascular staining. Digital clips were transferred to a personal computer, and SHI time-intensity curves were acquired in each section using Image-Pro Plus software (Media Cybernetics, Silver Spring, MD). Subharmoric fractional blood volumes were calculated, and the perfusion was estimated from the initial slope of the fractional blood volume uptake averaged over 3 injections, Subharmonic perfusion data were compared with the gold standard (ie, the microspheres) using linear regression analysis. Results. In vivo gray scale SHI clearly showed flow and, thus, perfusion in the kidneys with almost complete suppression of tissue signals. in total, 270 SHI time-intensity curves were acquired, which reduced to 94 perfusion estimates after averaging. Subharmonic perfusion estimates correlated significantly with microsphere results (r = 0.57; P < .0001). The best SHI perfusion estimates occurred for high perfusion states in the anterior of the kidneys (r = 0.731; P=.0001). The corresponding root mean square error was 2.4%. Conclusions. Subharmonic perfusion estimates have been obtained in vivo. The perfusion estimates were in reasonable to good agreement with a microvascular staining technique.