A comparison of video and digital data in the assessment of myocardial perfusion abnormalities by myocardial contrast echocardiography

Objective: The objective of the present study was to compare the digital and video data of myocardial contrast echocardiography (MCE) to assess altered myocardial blood flow produced by graded coronary stenoses. Methods: Three grades of left anterior descending (LAD) coronary artery stenosis and occlusion were created in eight open-chest canine models. MCE was performed with BR1 infusion by harmonic power Doppler with ECG gated intermittent triggered imaging at pulsing intervals ranging from 1:1 to 1:10. For images that were recorded simultaneously on both a videotape (video data) and an optical disk (digital data), myocardial signal intensity in the LAD region was plotted vs. pulsing intervals and was fitted to an exponential function:y=A(1 − e^−bt ), where A is the peak plateau signal intensity, and b is the rate of signal intensity rise for quantification of myocardial blood flow. Results: Both values for A and b progressively decreased with a greater level of stenosis. The correlation of A with myocardial blood flow (determined by use of fluorescent microspheres) was weak with digital data (r= 0.38, p= 0.037), and was insignificant with video data (r= 0.16, p= 0.38). The correlation of b with microsphere-derived myocardial blood flow was better than that of A with both video and digital data, and was similar between the two kinds of data (video:r= 0.69, p < 0.0001; digital:r= 0.68, p < 0.0001). Conclusions: Video and digital MCE data are equivalent in their ability to quantify altered myocardial blood flow produced by graded coronary stenoses.     

Pulsed tissue Doppler imaging for the detection of myocardial ischaemia, a comparison with myocardial perfusion SPECT

In order to compare the diagnostic ability of pulsed tissue Doppler and myocardial perfusion Single Photon Emission Computed Tomography (SPECT) in patients with a history of unstable coronary artery disease, CAD, 26 patients, 22 men and four women, age 47-76 years, were investigated in a prospective study, 5-10 day after an episode of unstable angina. Tissue Doppler and two-dimensional echocardiography were performed during dobutamine stress testing and myocardial scintigraphy after bicycle exercise and at rest. Patients with a normal SPECT had higher peak systolic velocity during dobutamine infusion, 18.9 +/- 4.1 cm s(-1), than patients with ischaemia, 12.2 +/- 3.8 cm s(-1) (P<0.001) or scar, 8.8 +/- 3.0 cm s(-1) (P<0.01). In a territorial analysis the difference in peak systolic velocity between areas with a normal and abnormal SPECT was less apparent. Failure to achieve >/=13 cm s(-1) in mean-peak systolic velocity was the most accurate criterion for detection of significant CAD on SPECT. We conclude that pulsed tissue Doppler can be used for objective quantification of left ventricular wall motion during dobutamine stress testing and for identification of patients with CAD on SPECT but not for identification of regional ischaemia.     

A new device combining laser Doppler perfusion imaging and digital photography

Summary. We describe a new method for acquisition and analysis of skin perfusion images acquired by laser Doppler scanning and digital photographs of the area scanned. Photographs are obtained with a commercial digital still video camera. A commercial software package is used to handle the perfusion image file and the digital photo. We describe software developed to assess blood flow distribution in detail in relation to the visual appearance of the skin, palpatory findings and other clinical signs. Possible clinical applications of the method described by case reports are post-operative evaluation of vascularized grafts and monitoring of treatment of chronic skin ulcers.     

多巴酚丁胺负荷超声下斑点追踪与组织多普勒技术检测存活心肌的临床价值

目的 探讨超声斑点追踪技术(STE)与组织多普勒技术(TDI)分别联合多巴酚丁胺负荷试验检测存活心肌的临床价值.方法 左心室收缩功能下降(左心室射血分数＜50％)冠心病患者37例,在血运重建之前进行联合多巴酚丁胺负荷超声心动图(DSE)的STE与TDI检查,分析计算室壁运动异常节段(RWMA)的静息及DSE后纵向应变率(LSR)和收缩期峰值速度(PSV).血运重建后1、3、6个月分别复查超声心动图,室壁运动改善为判定存活心肌的金标准,分析STE与TDI检测存活心肌的价值.结果 检查RWMA214个,金标准检测119个节段为存活心肌,95个节段为非存活心肌.存活心肌与非存活心肌的LSR和PSV在静息状态下比较差异有统计学意义(P＜0.01),存活心肌组的LSR和PSV在DSE前后比较差异有统计学意义(P＜0.01),而非存活心肌组的LSR和PSV在DSE前后差异无统计学意义(P＞0.05).受试者工作特征(ROC)曲线判定以△LSR(％)≥7.14％为截断点,检测存活心肌的敏感度88.2％,特异度80.0％;以△PSV(％)≥8.04％为截断点,检测存活心肌的敏感度74.8％,特异度83.2％.联合运用LSR和PSV两项指标,检测存活心肌的敏感度和特异度分别提高至89.8％、88.7％.结论 STE与TDI联合DSE检测存活心肌的敏感度和特异度有明显提高,适宜在临床推广使用.     

Real-time myocardial contrast stress echocardiography using bolus application

In myocardial contrast echocardiography (MCE), power modulation technique may quantify myocardial perfusion in real-time. However, constant infusion of the contrast agent (CA) complicates handling. This pilot study sought for the clinical feasibility of quantitative MCE by a CA bolus application during Adenosine stress echocardiography to diagnose coronary artery disease (CAD). Twenty-four consecutive patients (pts) with contemporary coronary angiography underwent rest and maximum Adenosine stress. Signal intensity could be calculated in 316/348 left ventricular (LV) segments (91%) (18-segment model). At rest, gamma-variate (alpha) as well as saturation function (beta) was not significantly different in healthy men (n = 268) as well as CAD pts (n = 48) (alpha: 0.34 s(-1) versus 0.40 s(-1), n.s.; beta: 0.31 s(-1) versus 0.35 s(-1), n.s.). During Adenosine infusion both values increased in healthy men (alpha: 0.34 +/- 0.37 s(-1) versus 0.44 +/- 0.45 s(-1), p < 0.05; beta: 0.31 +/- 0.33 s(-1) versus 0.40 +/- 0.40 s(-1), p < 0.01), but not in CAD (alpha: 0.40 +/- 0.35 s(-1) versus 0.29 +/- 0.29 s(-1), n.s.; beta: 0.35 +/- 0.32 s(-1) versus 0.27 +/- 0.30 s(-1), n.s.). Sensitivity of alpha/beta reserve 相似文献   

Trends in myocardial contrast echocardiography: parameteric versus volumetric imaging

It is now possible to perform myocardial contrast echocardiography at the bedside with an intravenous injection of commercially available contrast media. Although myocardial contrast echocardiography is a sensitive method for the detection of coronary stenosis and myocardial viability, its diagnosis has relied largely on the subjective interpretation of regional perfusion by experienced clinicians. Thus, quantification of myocardial contrast echocardiography data and displaying comprehensive images have been necessary for its routine application. In this review, new methods for quantifying or displaying myocardial contrast echocardiography parameters will be introduced: firstly, parametric imaging that displays the parameters of myocardial blood volume, blood flow velocity and myocardial blood flow separately; and secondly, color-coded maps of myocardial blood volume established from one myocardial contrast echocardiography image. These quantitative techniques can provide comprehensive and easy-to-understand images, although the quality of the baseline image remains a critical factor.     

多普勒组织成像与二维超声检测梗死心肌运动的比较研究

目的 比较多普勒组织成像（TDI）速度图与常规二维（2D）超声图在检测急性心肌梗死患者节段性室壁运动异常的差异，评估TDI诊断梗死缺血心肌运动的价值。方法对48例健康者和22例急性心肌梗死患者行常规2D超声检查。对心尖四腔切面、二腔切面、左室长轴切面、胸骨旁左室长轴切面和短轴切面的室壁运动，使用TDI技术测量各室壁节段内膜下心肌运动峰值速度。在心尖左室长轴上计算跨壁速度梯度。当测量值低于正常对照值下限（均数～1．96标准差），则判断为室壁运动异常。设置对TDI速度图检测数据的可重复性检验。结果TDI速度图对室壁运动异常总的检出率显著高于2D超声（P〈0.01）。依据6例冠状动脉造影结果发现，TDI速度图检测梗死和缺血心肌的准确性和敏感性高于2D超声（P〈0.05），但其特异性低于后者。TDI速度图检测所得的数据有较好的可重复性。结论在检测梗死和缺血心肌室壁运动异常方面。TDI优于常规2D超声。     

B-flow imaging of internal carotid artery stenosis: Comparison with power Doppler imaging and digital subtraction angiography

PURPOSE: Digital subtraction angiography (DSA) is the gold standard in the diagnosis of carotid artery stenosis, but it has a relatively high complication rate. We evaluated the efficacy of B-flow imaging (BFI) in examining internal carotid artery stenosis (ICAS) compared with power Doppler imaging (PDI) and DSA. METHODS: We performed BFI, PDI, and DSA on 56 consecutive patients with suspected ICAS. The degree of stenosis was calculated for each technique, and results of BFI and PDI were then correlated with those of DSA. RESULTS: Measurements of the percentage of stenosis made using both sonographic techniques were significantly correlated with those of DSA (p < 0.0001). However, the coefficient of correlation between DSA and BFI (r = 0.94) was higher than that between DSA and PDI (r = 0.87). The mean difference between ICAS measurements with BFI and DSA was -1.3% (95% confidence interval [CI], -2.5 to 0). The mean difference between ICAS measurements with PDI and DSA was -6.5% (95% CI, -8.2 to -4.7). ICAS was graded significantly lower on PDI than on DSA, whereas BFI findings were similar to those of DSA. CONCLUSION: BFI shows high correlation with DSA and provides a more accurate planimetric evaluation of ICAS than PDI does.     

谐波能量显像评价正常犬肝脏声学造影的实验研究

目的 评价谐波能量显像（ＨＰＩ）在正常肝脏声学造影中的造影增强效果,并与彩色多普勒血流显像（ＣＤＦＩ）进行对比。方法 ４只健康杂种犬经外周静脉注射氟碳声学造影剂,分别用ＨＰＩ和ＣＤＦＩ观察肝脏。视觉判断彩色增强效果和伪像分级。结果 造影后,肝脏ＨＰＩ与ＣＤＦＩ均有３级强烈彩色信号增强,但ＣＤＦＩ有严重的３级“彩色怒放”伪像,而ＨＰＩ的彩色伪像均为１级。结论 ＨＰＩ在声学造影嗵较起初地反映肝脏血流灌     

Real-time myocardial contrast echocardiography for assessing perfusion and function in healthy and infarcted wistar rats

Real-time myocardial contrast echocardiography (MCE) is a noninvasive perfusion imaging method, whereas technical and resolution problems impair its application in small animals. Hence, we investigated the feasibility of MCE in experimental cardiovascular set-ups involving healthy and infarcted myocardium in rats. Twenty-five male Wistar rats were examined under volatile anesthesia (2.5% isoflurane) with high-resolution conventional 2-D echocardiography (2DE) and real-time MCE (Sonos 7,500 with 15MHz-transducer, Philips Medical Systems, Andover, MA, USA) in short-axis view. Contrast agent (SonoVue, Bracco, Milan, Italy) was infused as a bolus into a sublingual vein. Background-subtracted contrast signal intensity (SI) was measured off-line in six end-systolic segments and fitted to an exponential curve (gamma variate). Derived peak SI was subsequently calculated and compared with wall motion and common functional measured quantities (left ventricular end-diastolic diameter [LVEDD], area shortening [AS]). Recordings were performed before and 14 days after left anterior descending (LAD) ligature. Infarction induced anterior wall motion abnormalities (WMA) in all animals (16 akinetic, 9 hypokinetic), increased LVEDD (9.1 +/- 0.6 vs. 7.9 +/- 0.6 mm, p < 0.001), reduced AS (36.1 +/- 10.0 vs. 59.5 +/- 4.1%, p < 0.001) and reduced anterior segmental SI (0.4 +/- 0.4 dB akinetic / 1.7 +/- 1.7 dB hypokinetic vs. 15.8 +/- 10.9 dB preinfarct, p < 0.001 / p < 0.001). Segmental SI in normokinetic segments remained unchanged. Area at risk (perfusion defect) correlated well with WMA (r = 0.838). These data confirmed high-resolution real-time MCE as a rational tool for assessing myocardial perfusion of Wistar rats. It may therefore be a useful diagnostic tool for in-vivo cardiovascular research in small animals.     

Stress radionuclide myocardial perfusion imaging detects more residual ischemia than stress echocardiography following acute myocardial infarction

OBJECTIVES: This investigation sought to compare the abilities of stress radionuclide myocardial perfusion imaging and stress echocardiography to detect residual ischemia in patients following acute myocardial infarction (MI). BACKGROUND: Stress radionuclide myocardial perfusion imaging and stress echocardiography are both commonly used to assess patients (patients.) in the immediate post MI period. However, the relative value of these techniques in identifying post MI ischemia remains unclear. METHODS: Eighteen patients. underwent both dipyridamole radionuclide perfusion imaging and dobutamine stress echocardiography on the same day or on consecutive days, 3-7 days following uncomplicated acute MI. Pts. who had an acute percutaneous intervention were excluded. Images were reviewed with clinical information available, but blinded to the opposing modality, for perfusion defects, wall motion abnormalities (WMA), and evidence of ischemia (reversible defect(s) on perfusion imaging, worsening WMA on stress echocardiography). Of the 18 patients, 11 subsequently underwent cardiac catheterization. RESULTS: Perfusion imaging identified defects in 16 (89%) patients, of whom 15 (83% of total) were found to be ischemic. Stress echocardiography identified a fixed wall motion abnormality in 17 (94%) and ischemia in 8 (44%, p < 0.05 compared with perfusion imaging ischemia). Among 11 patients who underwent catheterization, there was a trend towards perfusion imaging identifying more ischemia in the territory of an obstructed (> or = 70%) vessel--100% (11/11) vs. 64% (7/11) for stress echocardiography (p = 0.09). CONCLUSION: In the immediate post-infarction period, dipyridamole stress radionuclide myocardial perfusion imaging more often shows evidence of residual ischemia than dobutamine stress echocardiography.     

Twinkling artifact in color Doppler imaging of the orbit.

OBJECTIVE: To show an artifact related to color Doppler flow imaging of the orbit. METHODS: Three patients with strongly reflective structures in the orbit were selected from those routinely referred by clinicians for color Doppler ultrasonography of the orbit. Gray scale and color flow images were obtained with a 7.5-MHz linear array probe for a region with strongly reflective structures. A spectral display was acquired to confirm the presence of blood flow. RESULTS: One patient had a metallic foreign body just behind the bulb; another had calcification within the irregular mass of phthisis bulbi; and the third had hyperechoic drusen in the periphery of the intraocular melanoma. The color mosaic, suggesting the presence of blood flow, was detected beyond all hyperechoic structures. Close vertical bands with no outer wrapping were detected in the spectrum display, obtained by placing the sample volume on the region of color flow. The artificial color flow was recognized as a color Doppler twinkling artifact. CONCLUSIONS: The color flow beyond the strongly reflecting structures in the orbit might be mistakenly interpreted as real blood flow if an examiner is not familiar with the artifact. It should prompt further imaging with spectral Doppler ultrasonography.     

间歇式谐波显像声学造影评价肾实质血流灌注

目的：评价间歇式谐波显像观察肾实质血流灌注声学造影的优越性。方法：自制的白蛋白包裹氟碳气体的造影剂对８只兔外周静脉造影。分别用基波显像、基波间歇显像、二次谐波显像、间歇式谐波显像四种成像方式观察造影效果。结果：间歇式谐波显像的视觉效果分级最高,视频密度值高达１６０．７４±３．７２,与其它组差异显著（Ｐ＜０．０１）,较基波显像延长造影峰值半降时间（１６．７±３．６ｓ,８．４±１．８ｓ）,差异显著（Ｐ＜０．０１）。结论：间歇式谐波显像能增强肾实质造影信号强度,延长造影时间,是一种较好的造影显像方法。     

实时心肌造影评价肥厚型心肌病患者心内膜下及心外膜下心肌灌注

目的应用实时心肌超声造影分析肥厚型心肌病（HCM）患者心内膜下及心外膜下心肌灌注状况,及其与室壁肥厚程度的关系,以评价肥厚型心肌病患者心肌微循环障碍。方法HCM患者26例,正常对照组20例,实时心肌超声造影观察心尖四腔、两腔、左心长轴切面实时动态图像,应用时间～强度曲线分析造影图像。结果HCM患者左室肥厚节段及非肥厚心肌节段的心内膜下及心外膜下心肌的A及A×k值低于对照组（P〈0．05）,k值高于对照组（P〈0．001）。HCM患者左室肥厚节段心内膜下及心外膜下心肌的的A及A×k值低于非肥厚心肌节段（P〈0．05）,k值高于非肥厚心肌节段（P〈0．05）。HCM患者心内膜下A、及A×k值低于下心外膜下（P〈0．001）。HCM患者肥厚节段心内膜下及心外膜下心肌A×k值与肥厚节段室壁厚度均呈负相关（r=-0．785,P〈0．001;r=-0．461,P〈0．05）。结论HCM患者肥厚节段与非肥厚节段的心内膜下及心外膜下心肌均存在微循环障碍,且以心内膜下心肌微循环损伤更为显著,同时,随着室壁厚度的增加,心肌血流灌注显著减少。实时心肌超声造影是评价HCM患者心肌微循环障碍的有效方法。     

High-sensitivity power Doppler imaging of normal superficial lymph nodes

PURPOSE: This study was conducted to describe the various patterns of vascularity of the normal superficial lymph nodes detected using high-sensitivity power Doppler imaging according to the dimension and anatomic location of the nodes. SUBJECTS AND METHODS: A total of 712 lymph nodes (416 in the neck, 205 in the groin, and 91 in the axilla) were studied in 118 patients with high-sensitivity Power doppler. Three categories of vascularity were defined: absence of vascularity (type 1), hilar and perihilar vascularity (type 2), and vascularity in the entire node (type 3). The 3 types of vascularity were correlated with the anatomic location and the dimension (maximum transverse diameter) of the nodes. RESULTS: Type 3 vascularity was found in all lymph nodes with a maximum transverse diameter > 6 mm, in the 67.9% (133/196) of lymph nodes between 4 and 6 mm in diameter, and in 45.7% (42/92) of lymph nodes between 2 and 4 mm in diameter. In lymph nodes with transverse diameters of 2-6 mm, type 3 vascularity was detected in 80.7% (46/57) of the axillary nodes, in 69.0% (87/126) of the inguinal nodes, and in 40.0% (42/105) of the cervical nodes. Type 2 vascularity was seen in 14.2% (101/712) of all examined lymph nodes. The absence of vascularity (type 1) was noted in only 1.9% (8/416) of cervical and 2.0% (4/205) of inguinal nodes. CONCLUSIONS: State-of-the-art power Doppler equipment can demonstrate type 3 vascularity in a high percentage of normal superficial lymph nodes. This pattern of intense, extensive-but harmonious-vascularity must be considered as an indicator of benignity.     

Assessment of resting perfusion defects in patients with acute myocardial infarction: comparison of myocardial contrast echocardiography, combined first-pass/delayed contrast-enhanced magnetic resonance imaging and 99mTC-sestamibi SPECT

Background Information on the accuracy of both magnetic resonance imaging (MRI) and myocardial contrast echocardiography (MCE) for the identification of perfusion defects in patients with acute myocardial infarction is limited. We evaluated the accuracy of MRI and MCE, using Single Photon Emission Computed Tomography (SPECT) imaging as reference technique.Methods Fourteen consecutive patients underwent MCE, MRI and ^99mTc-MIBI SPECT after acute myocardial infarction to assess myocardial perfusion. MCE was performed by Harmonic Power Angio Mode, with end-systolic triggering 1:4, using i.v. injection of Levovist^®. First-pass and delayed enhancement MRI was obtained after i.v administration of Gadolinium-DTPA. At MCE, homogeneous perfusion was considered as normal and absent or “patchy” perfusion as abnormal. At MRI, homogenous contrast enhancement was defined as normal whereas hypoenhancement at first-pass followed by hyperenhancement or persisting hypoenhancement in delayed images was defined as abnormal.Results At MCE 153 (68%) of segments were suitable for analysis compared to 220 (98%) segments at MRI (p<0.001). Sensitivity, specificity and accuracy of MCE for segmental perfusion defects in these 153 segments were 83, 73 and 77%, respectively. Sensitivity, specificity and accuracy of MRI were 63, 82, and 77%, respectively. MCE and MRI showed a moderate agreement with SPECT (k: 0.52 and 0.46, respectively). The agreement between MCE and MRI was better (k: 0.67) that the one of each technique with SPECT.Conclusion MCE and MRI may be clinically useful in the assessment of perfusion defects in patients with acute myocardial infarction, even thought MCE imaging may be difficult to obtain in a considerable proportion of segments when the Intermittent Harmonic Angio Mode is used.     

实时心肌超声造影评估心肌灌注的临床研究

目的探讨冠状动脉支架置入术前后局部心肌血流灌注的变化。方法对7例正常人和20例冠心病患者支架术前后,分别行实时心肌超声造影检查,根据造影剂的充盈程度进行评分,并观察双嘧达莫负荷前后闪烁显像时,心肌血流再灌注状况。结果治疗前缺血心肌的造影记分指数负荷前后均低于正常心肌,支架术后灌注明显改善,基础状态和负荷后的造影记分、记分指数较术前好转。结论冠状动脉支架置入术可改善缺血心肌血流灌注,实时心肌超声造影可评价心肌微循环灌注。     

组织多普勒评价胸部放疗对肿瘤患者心脏功能影响的临床研究

目的：探讨常规超声心动图（Echocardiography）和组织多普勒技术（Tissue Doppler Imaging， TDI）在评价胸部放疗对心脏功能影响方面的临床应用价值。方法：将120例患者依据是否联合化疗及化疗剂种类分为单纯放疗组（I），放疗联合蒽环类化疗组（II），放疗联合其它化疗剂组（III）。测定并比较120例胸部肿瘤患者放疗前和放疗后6个月的常规参数及组织多普勒参数。健康志愿者29例，作为平行对照组，记录其在相同的时间间隔内上述参数变化。结果：与放疗前相比，组织多普勒显示房室瓣瓣环及右室游离壁收缩期运动速度峰值、心室舒张早期运动速度峰值比放疗前降低，而心房收缩期运动速度峰值升高。其中，II组上述参数改变比I组和III组更为明显；III组的心脏损害亦较I组为著。仅有34例（28.3%）患者放疗后出现常规左室舒张功能指标异常。12例（10%）患者放疗后出现常规右室舒张功能指标异常。肺动脉高压2例。但左心室收缩功能参数、室间隔（IVS）及左室后壁（LVPW）的室壁增厚率（ΔT）；平行对照组在首次检查6月后未发现常规超声心动图检查及组织多普勒参数明显改变。结论：常规超声心动图及组织多普勒技术可用于评价放疗所致的早期心脏功能异常，与常规超声心动图检查相比， TDI技术能更早、更敏感地评价放疗致心脏功能损害。放疗联合应用化疗可加重心脏损害，尤以联合蒽环类化疗剂为重。