Echo contrast agents improve flow display of color Doppler: in vitro studies

Flow detection by color Doppler is impaired by low velocity of flow and increasing attenuation and depth of ultrasound penetration. The effects of increased echogenicity on flow detection (Toshiba SSH 65A) were thus studied in a flow model, which yielded similar strengths of Doppler signals as seen in the clinical routine, by adding microbubble solutions to the blood analog fluid (45% aqueous glycerin) and comparing signal strength (score 0-5) prior to and after contrast. The flow within the plexiglass tube with less than 3 degrees angle of coincidence for Doppler interrogation was laminar with a parabolic velocity profile at physiological velocities and pressures. In comparison with various contrast agents at a flow velocity of 18 cm/sec and 19 dB attenuation, flow was not detectable in control color Doppler, after 4 mL of the blood analog fluid, and after 4 mL of an agitated saline solution 9 mg/mL, but visible after 4 mL of Echovist, a polysaccharide solution with reproducible bubble size and concentration and after 4 mL of an agitated polygelatin solution. Increasing concentration of Echovist (50-400 mg/mL) improved flow detection. Echovist 200 mg/mL enhanced the score by 1.1 + -0.6 for velocities 5-20 cm/sec (P less than 0.01), by 1.6 + -0.8 for 40-100 cm/sec (P less than 0.001), and by 1.1 + -0.6 for velocities greater than 150 cm/sec (P less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)     

Color-coded Doppler imaging of systolic flow patterns in hypertrophic cardiomyopathy

We studied 11 patients with hypertrophic cardiomyopathy by color Doppler echocardiography (Group I: 6 patients with outflow obstruction, and Group II: 5 patients without outflow obstruction) to assess systolic structure and function as observed by cross-sectional echocardiography in relation to the flow dynamics. The structure and function included systolic anterior motion of mitral valve (SAM), midsystolic aortic valve closure (AoC), systolic cavity obliteration and the presence and timing of mitral incompetence. Their occurrence and timing was related to presence of aortic systolic flow and presence of turbulence. While all patients in Group I had SAM and turbulence, none of the patients in Group II had SAM nor turbulence. Early mitral incompetence appearing before SAM and turbulence, occurred in all patients of Group I and in none of Group II. Midsystolic aortic valve closure was only present in Group I and blood flow was unilaterally directed so that only 60% of aortic cross-sectional area showed blood flow. We conclude that mitral incompetence in hypertrophic cardiomyopathy in early systole is common when outflow gradient is present and is independent of mitral incompetence of mid- and late systole. During SAM, turbulence in the subaortic area and mid and late mitral incompetence occurred simultaneously. The midsystolic aortic valve closure was related to the unilaterally directed blood flow through the aortic cross-sectional area.     

Noninvasive assessment of renal artery stenosis by combined conventional and color Doppler ultrasound

We describe four angiographically-proven patients in whom Doppler color flow imaging in conjunction with conventional Doppler correctly diagnosed significant renal artery stenosis in three and ruled out stenosis in the fourth case.     

彩色多普勒血流显像评价“肾通注射液”对急性肾功能衰竭家兔肾血流量的影响

目的　采用彩色多普勒血流显像评估“肾通注射液”对急性肾功能衰竭家兔肾血流量的影响。方法　 30只健康雄性大耳白兔分为正常组、模型组、肾通治疗组 ,每组 10只 ,肌注 5 0 %甘油等渗盐水制造急性肾小管坏死模型 ,正常对照组同法注射等容量生理盐水。造模后 1h,治疗组腹腔注射肾通注射液 (肾通组 ) ,正常组和模型组腹腔注射等容量 5 %葡萄糖 ,生化法监测肾功能 ,彩色多普勒血流显像动态观察各组家兔治疗后 2 4 h、4 8h、72 h肾血流动力学变化。结果　肾通组肾血流量较模型组显著升高 ,各级动脉阻力指数显著降低。肾功能各项指标均有显著改善。结论　“肾通注射液”可改善急性肾功能衰竭家兔肾血液供应 ,彩色多普勒血流显像可定量检测肾血流量     

In vitro analysis of jets by Doppler colour flow imaging: the importance of time to maximum jet area

Regurgitant jets were simulated in vitro and analysed using Doppler colour flow imaging. The regurgitant volumes were estimated using total jet area (JA), variance area (VA), and the maximum area of variance x time to maximum area of variance (MAVT). Both flow rate and injected volume were significantly correlated to area of variance (r = 0.89 and r = 0.98, respectively) for a given orifice size. When MAVT was analysed, it correlated better to injected volume (r = 0.97) at a fixed flow rate, than varying flow rate (r = 0.69) at a fixed injected volume. The relationship between MAVT and injected volume was also examined with varying flow rate. There was a highly significant correlation between MAVT and injected volume under these circumstances (r = 0.99). A similar relationship between MAVT and injected volume was found when the orifice size was altered. Using multivariate regression analysis the injected volume was best defined by MAVT (R2 = 0.88). The addition of orifice size only improved the fit to the model marginally (R2 = 0.90). These data document the importance of analysing the time to maximum area of variance when applying Doppler colour flow imaging to regurgitant jets. MAVT is a better predictor of regurgitant volumes in vitro compared with jet sizes alone and may have potential use in man to quantify the severity of regurgitant valve lesions.     

彩色多普勒超声对主-肺动脉间隔缺损的诊断价值

目的　探讨彩色多普勒超声 ( CDFI)对主 -肺动脉间隔缺损的 ( APSD)诊断价值。方法　应用彩色多普勒超声的二维图像 ,多普勒频谱和彩色显像对 3例主 -肺动脉间隔缺损的解剖及血流动力学异常进行观察。结果　行 CD-FI检查 3例患者 ,诊断为 APSD,其中 型 2例 , 型 1例 ,合并室间隔缺损 1例 ,均经手术证实。APSD彩色多普勒超声特征是 :主 -肺动脉内异常高速血流由升主动脉射入 ,主 -肺动脉扩张 ,左、右肺动脉增宽 ,左心增大。结论　CD-FI可用作诊断 APSD的首选方法 ,具有无创、安全、准确及可重复应用等优点     

Doppler color flow image size: dependence on instrument settings

Doppler color flow imaging provides important qualitative information about the location and spatial distribution of intracardiac blood flow. However, the effect of instrument-related variables on the size of color Doppler images requires further definition. Flow of a silicone particle solution was established in a tube or cylinder and scanned as color gain, pulse repetition frequency, depth, and transducer frequency were varied. The diameter of Doppler color flow images were measured during constant laminar or disturbed flow parallel to the ultrasound beam and during laminar flow perpendicular to the ultrasound beam. The diameter of color Doppler images of laminar flow perpendicular and parallel to the beam varied directly with color gain. Diameter varied inversely with transducer frequency for laminar flow parallel to the transducer and inversely with pulse repetition frequency for laminar flow perpendicular to the transducer. The diameter of laminar flow parallel to the transducer varied directly with the depth of the flow area below the transducer. The size of the color flow dropout of laminar flow exactly perpendicular to the ultrasound beam varied directly with transducer frequency and inversely with gain. During disturbed flow parallel to the transducer, the diameter of the image varied directly with gain and inversely with transducer frequency and pulse repetition frequency. Instrument settings have a significant impact on the size of color Doppler images. Understanding the effects of changes in these variables is important for reliable diagnostic use of Doppler color flow imaging.     

Spontaneous intrahepatic portosystemic venous shunt in a patient with cirrhosis: diagnosis by combined color Doppler and pulsed Doppler ultrasonography

Abstract: Large spontaneous intrahepatic portosystemic venous shunts are occasionally found and their diagnosis by Doppler sonography is rarely reported. The authors describe a case of spontaneous intrahepatic porto-systemic venous shunt in liver cirrhosis diagnosed by color Doppler and characterized by an unusual pulsed Doppler spectrum: a continuous flat portal-like pattern of flow in the portal branch, and in both the shunt and the hepatic vein,     

彩色多普勒血流显像技术监测肝移植术后发生血管并发症的时间分析

目的 探讨彩色多普勒血流显像(CDFI)技术在监测肝移植术后发生血管并发症时间分布的意义.方法 对792例肝移植患者在术后不同时间进行CDFI检查,并对CDFI诊断血管并发症的患者进行血管造影、螺旋CT检查或手术确诊.结果 在792例肝移植患者中,发生血管并发症共54例,发生时间在术后1～360d,其中在1～30d,31～60d、61～90d,91～180d和181～360 d发生血管并发症的构成比分别为46.3%(25/54)、22.2%(12/54)、14.8%(8/54)、9.3%(5/54)和7.4%(4/54).其中肝动脉并发症、门静脉并发症及流出道梗阻的构成比分别为61.1%(33/54)、35.2%(19/54)和3.7%(2/54).结论 大多数血管并发症发生在术后6个月,肝移植术后连续密切CDFI监测有利于早期发现血管并发症.     

Combined femoral pseudoaneurysm and arteriovenous fistula: diagnosis by Doppler color flow mapping

This case report is the first to describe a combined femoral pseudoaneurysm and arteriovenous fistula resulting from a cardiac catheterization, diagnosed by color Doppler.     

The physiology of congenital heart disease: assessment by Doppler color flow mapping

The use of Doppler echocardiography is a routine part of the noninvasive assessment of the patient with heart disease. In children with congenital heart disease, pulsed- and continuous-wave Doppler echocardiographic techniques provide accurate, reproducible hemodynamic data relative to structural defects. Doppler color flow imaging, however, allows for qualitative assessment of blood flow patterns, which may give important insights into the changing physiology of the newborn infant or that of a patient in the medical or surgical intensive care settings. Ten cases are presented in which this flow information is instructive in understanding the physiological sequelae of congenital heart disease.     

The usefulness of cross-sectional Doppler flow imaging in the detection of small ventricular septal defects with left-to-right shunt

Small ventricular septal defects (VSDs) with left to right (L–R)shunt have been difficult to diagnose with conventional ultrasoundtechniques. Using the cross-sectional Doppler flow imaging system,additional information can be obtained. In a group of 60 patientswith a clinical diagnosis ofVSD with L–R shunt, the newtechnique proved valuable, especially in detecting muscularand apical VSDs.     

The usefulness of cross-sectional Doppler flow imaging in the detection of small ventricular septal defects with left-to-right shunt

Small ventricular septal defects (VSDs) with left to right (L–R)shunt have been difficult to diagnose with conventional ultrasoundtechniques. Using the cross-sectional Doppler flow imaging system,additional information can be obtained. In a group of 60 patientswith a clinical diagnosis ofVSD with L–R shunt, the newtechnique proved valuable, especially in detecting muscularand apical VSDs.     

Influence of the orifice inlet angle on the velocity profile across a flow convergence region by color Doppler in vitro

The converging flow field proximal to a leaking valve is determined among other things by the orifice inlet angle formed by the leaflets. Thus, the inlet angle affects the determination of regurgitant flow rate by the flow convergence method. Based on the hypothesis of spheric isovelocity surfaces, others had postulated that a local velocity within the flow convergence should change inversely proportional to changes in the three-dimensional inlet angle. This concept would allow correction of the determination of regurgitant flow for nonplanar orifice inlet angles. We tested this concept in vitro. In a flow model, the flow convergence region proximal to different orifice plates was imaged by color Doppler: funnel-shaped, planar and tip-shaped (inverted funnels) orifice plates, with circular orifices of 2- and 7-mm diameter. Velocity profiles across the flow convergence along the flow centerline were read from the color maps. As predicted, the local velocities were inversely related to the inlet angle, but only at the 2-mm funnel orifices, this effect was inversely proportional to the three-dimensional inlet angle (i.e., in agreement with the mentioned concept). However, for any 7-mm orifice and/or inlet angle of > 180 degrees, the effect of the inlet angle was considerably less than predicted by the aforementioned concept. With increasing orifice diameter and with decreasing distance to the orifice, the effect of the orifice inlet angle was reduced. The effect of the orifice inlet angle on the flow convergence region is modulated by orifice size and the distance to the orifice. Therefore, correction of flow estimates in proportion to the three-dimensional inlet angle will lead to considerable errors in most situations of clinical relevance, namely to massive overcorrection when analyzing velocities located close to wide orifices.     

彩色多普勒血流显像监测肝移植术后门静脉并发症

目的探讨彩色多普勒血流显像技术（CDFI）监测对肝移植术后门静脉并发症的诊断价值.方法应用CDFI对504例原位肝移植患者进行术前和术后连续监测.术前监测内容包括门静脉主干直径、血流速度及有无门静脉栓塞等;术后监测内容包括门静脉供体段、受体段、吻合口的直径、管腔内回声、血流方向及血流速度等.结果术后当日门静脉平均血流速度为46.27 cm/s,最小流速为15.8 cm/s,最大流速为110.8 cm/s.358例（71.03%）血流速度＞40 cm/s.30 d后,347例（68.85%）流速降至40 cm/s以下.64例（12.70%）出现离肝血流,1例（0.20%）出现完全离肝血流.门静脉并发症13例（2.58%）,包括4例（0.79%）栓塞（3例血栓、1例瘤栓）,9例（1.79%）吻合口周围狭窄.结论异常门静脉血流信号不一定均出现并发症,连续动态观察门静脉血流的变化更有价值,因此,CDFI技术对监测肝移植术后门静脉并发症的诊断具有重要作用.     

Usefulness of ultrasonography and Doppler color flow imaging in the diagnosis of internal jugular phlebectasia

Summary A 20-year-old woman presented to our hospital for investigation of a left neck mass. Ultrasonographic examination of the jugular mass demonstrated an echo-free space, the caliber of which markedly increased when the patient shifted from the sitting to the recumbent position or performed a Valsalva maneuver. On color Doppler flow imaging, a slow flow signal flowing in the direction opposite to that of the common carotid artery was found within this space. Ultrasonography and color Doppler flow imaging thus proved to be useful for correctly diagnosing internal jugular phlebectasia.     

Evaluation of left ventricular function in cardiomyopathic mice by tissue Doppler and color M-mode Doppler echocardiography

Tissue Doppler imaging (TDI) and color M-mode Doppler flow propagation velocity (Vp) are used to assess cardiac function in humans, but the feasibility and applicability of these measurements to murine cardiomyopathic models of heart failure remain unclear. Left ventricular (LV) function was measured by TDI and Vp among mice exhibiting severe dilated cardiomyopathy (TOT), pressure-overload hypertrophy (TAC), and normal controls (NTG). Transmitral flow pattern in TACs and TOTs showed a restrictive filling pattern, but early diastolic mitral annulus velocity was comparable among the three studied groups. Propagation velocity in an anesthetized state was comparable in all three groups. However, while Vp increased in all three groups in the conscious state, the increase in NTGs was statistically greater than in TACs and TOTs. Collectively, results indicate that color M-mode Doppler echocardiography can be used to assess LV function in mice. Furthermore, Vp is depressed by anesthesia, a complication that can lead to misinterpretation of LV function in normal hearts.     

New method for quantitatively determining aortic regurgitant volume using Doppler color flow imaging: experimental validation study

We have developed a method to provide the two-dimensional distribution of blood flow velocity and the blood flow volume rate in the ascending aorta from the cross-sectional Doppler color flow image. Regional blood flow velocities were determined by converting color intensities of the cross-sectional Doppler color flow image into the corresponding flow velocities with the correction with the spatial ultrasound beam incident angle. The spatial ultrasound beam incident angle was estimated from the geometric characteristics of the color flow image contour. The method was validated in a steady flow model circuit comparing the calculated flow volume rates by the method with those simultaneously measured by an electromagnetic flowmeter. We performed an open chest dog experiment and calculated the blood flow volume rate at the ascending aorta before and after the aortic regurgitation was made. The calculated ejection flow volume rate and regurgitant volume were validated by the comparison with those simultaneously measured by an electromagnetic flowmeter. Based on these data, we can conclude that the current method provides accurate measurements of regurgitant volume as well as ejection flow volume rate in the ascending aorta.     

糖尿病肾血流变化的彩色多普勒超声观察

用彩色多普勒血流显象（ＣＤＥＩ）和脉冲多普勒超声心动图（ＰＤＥ）检测２６例肾功能正常的非胰岛素依赖型糖尿病病人及２０例正常人的双侧肾动脉血流，以探讨糖尿病肾病血流动力学改变。糖尿病病人与正常人对照，肾动脉内径增宽（Ｐ〈０．０１），血流量增加（Ｐ〈０．０１），搏动指数及阻力指数降低（Ｐ〈０．０５）。结果表明，糖尿病临床肾病前期呈高灌注、低阻力改变。提示ＣＤＦＩ和ＰＤＥ可为临床异期发现糖尿糖尿病肾病提     

应用彩色多普勒超声检测脑血流灌注评价血管性痴呆

目的:探讨采用彩色多普勒超声检测颈内动脉及椎动脉血流估测脑血流灌注在评价血管性痴呆(VD)中的价值。方法:VD患者56例,对照组42例,采用GE Vivid 7彩色多普勒超声诊断仪,检测颈内动脉和椎动脉颅外段的血管内径、收缩期最大峰值流速(Vm)及流速-时间积分(VTI)以计算颈内动脉及椎动脉的每分血流量,2者相加获得总的血流量。结果:VD组双侧颈内动脉和椎动脉的Vm、颈内动脉血流量和总血流量均较对照组下降(P<0.05)。MMSE评分与总血流量呈正相关。结论:通过彩色多普勒超声对颈内动脉、椎动脉血流量指标进行检测,可较准确反映血管性痴呆患者脑血流灌注的改变,是一种研究血管性痴呆的有效方法和手段。