Quantification of vascular stenosis with color Doppler flow imaging: in vitro investigations

The accuracy of quantifying the degree of vascular stenosis with color Doppler flow imaging (7.5-MHz, linear array system) was determined in an experimental study carried out on six concentric and five eccentric model stenoses (cross-sectional area reduction, 13.4%-93.8%). The measurements were made with use of pulsatile flow at four different flow rates (70.8-339.0 mL/min). The degree of stenosis was calculated from the ratio of prestenotic to intrastenotic flow velocity. The most exact measurement of the degree of stenosis could be achieved with Doppler spectral analysis by determining the maximum peak systolic velocity (r = .994, y = 0.98x - 3.2). With the velocity values derived only from the color-coded image, it was also possible to find the most exact degree of stenosis (r = .995, y = 0.99x - 2.9). For quantification of stenosis, pre- and intrastenotic Doppler spectral analysis is no longer necessary if the stenosis can be imaged sufficiently with color Doppler.     

彩超对锁骨下动脉窃血综合征的诊断分析

目的 探讨彩超对锁骨下动脉窃血综合征（SSS）的诊断价值。方法 分析20例临床诊断为SSS的椎动脉血流与锁骨下动脉、颈动脉、无名动脉病变及上肢动脉血流频谱的关系。结果 SSS的椎动脉血流可分为完全性椎动脉反流、部分性椎动脉反流和无椎动脉反流三种。结论 超声诊断SSS方法简便、经济、无创。     

Cine MR imaging in mitral regurgitation: comparison with color Doppler flow imaging

Cine MR imaging is a new technique that combines short repetition times, limited flip angles, gradient-refocused echoes, and cardiac gating. This procedure was performed in 20 patients in whom mitral regurgitation was shown on left ventriculography, and the results were compared with those of color Doppler flow mapping. In all cases, mitral regurgitation on cine MR imaging was depicted as an area of decreased signal intensity within the left atrium. The extent and severity of the regurgitant jet as seen by the two techniques were classified visually as 4+ (severe), 3+ (moderate), 2+ (mild), and 1+ (minimal). The results of the two methods were the same in 14 (70%) of the 20 patients. In five patients the results differed by one grade and in one patient by two grades. In addition, the maximal intrusion distance and area of the regurgitant jet divided by the area of the left atrium as determined by the two methods were compared. The correlation coefficients between the two methods in regard to the length and area of mitral regurgitation were .74 and .71, respectively. These data suggest that the accuracy of cine MR imaging in assessing the severity of mitral regurgitation is comparable to that of color Doppler flow imaging.     

彩色多普勒超声在Graves''''病诊断中的作用

目的:探讨彩色多普勒超声在Graves’病(又称弥漫性甲状腺肿)诊断中的作用。方法:用能量多普勒超声观察40例Graves’病患者及40例正常对照组双侧甲状腺组织的血液供应及分布情况;用脉冲多普勒测量颈总动脉的收缩期峰值流速(VPS),甲状腺上动脉的收缩期峰值流速(VPS)及阻力指数(RI),测量甲状腺上动脉的内径。结果:Graves’病组甲状腺实质内的血供极为丰富,血流分级以Ⅲ级为主,呈“火海征”,Graves’病组与正常对照组相比有显著性差异,P<0.005。Graves’病组颈总动脉的收缩期峰值流速为(162.1±31.5)cm/s,正常对照组颈总动脉的收缩期峰值流速为(98.2±20.9)cm/s,Graves’病组甲状腺上动脉的收缩期峰值流速(108.7±35.6)cm/s,正常对照组甲状腺上动脉的收缩期峰值流速(42.1±15.1)cm/s,以上各参数Graves’病组甲状腺上动脉的阻力指数为0.55±0.11,正常对照组甲状腺上动脉的阻力指数为0.73±0.19。Graves’病组与正常对照组相比有显著性差异P<0.01。Graves’病组甲状腺上动脉的内径为3.34±1.16mm,正常对照组甲状腺上动脉的内径为1.62±1.24mm。Graves’病组与正常对照组相比有显著性差异P<0.01。结论:彩色多普勒超声在Graves’病诊断中有重要的作用。     

Doppler color flow imaging of common carotid artery dissection

Summary Sonographic findings are reported in a case of common carotid artery dissection assessed by Doppler color flow imaging and confirmed by angiography. Advantages and clinical relevance of this new ultrasound method for this diagnosis are discussed.     

Deep veins of the calf: assessment with color Doppler flow imaging

The authors studied the ability of real-time ultrasound aided by color Doppler flow imaging to demonstrate the deep veins of the calf in ten healthy subjects and 49 patients (91 limbs) with suspected deep venous thrombosis. Posterior tibial and peroneal veins demonstrated flow accentuation in 98% (74 of 75) and 96% (72 of 75), respectively, of the limbs without thrombosis and in all 20 normal limbs. Sixteen legs were involved with deep venous thrombosis. Peroneal veins could not be seen in three legs with marked calf swelling due to proximal thrombosis. There were two cases of thrombosis limited to the calf, nine of popliteal thrombosis (seven with contiguous spread of thrombus), and five of thrombosis limited to above the knee (four with sparing of the deep veins of the calf). Visualization of anterior tibial veins, achieved in 65% of all legs, did not correlate with thrombosis. The authors conclude that color Doppler flow imaging can demonstrate patency of posterior tibial and peroneal veins in most patients without deep venous thrombosis and aid in detection of below-the-knee thrombosis.     

彩超对动脉瘤腔内隔绝术后内漏的诊断价值

目的:探讨彩色多普勒超声对动脉瘤腔内隔绝术后内漏的诊断价值。方法:回顾性分析30例腹主动脉瘤患者腔内隔绝术后二维及彩色多普勒超声表现。结果:30例患者中6例出现内漏,发生率为20%,其中Ⅰ型1例,Ⅱ型4例,Ⅲ型1例。其中5例经CT证实,随访时间延长,3例患者内漏消失。结论:彩超是动脉瘤腔内隔绝术后诊断内漏有价值、可信赖,经济的检查方法。     

Study of normal Chinese vertebral-basilar arteries with transcranial color Doppler flow imaging

OBJECTIVE: The aim of this study was to evaluate the blood flow characteristics of intracranial vertebral-basilar artery (V-BA) in healthy Chinese adults with transcranial color Doppler flow imaging (TCDFI) and provide reference values of healthy people of different ages and genders. METHODS: Three hundred healthy Chinese adults were divided into three groups based on their ages: Group I: 20-39 years, Group II: 40-59 years, Group III: >/=60 years. Each group was subdivided into two subgroups according to their gender. Peak systolic velocity (Ps), end-diastolic velocity (Vd), time average maximum velocity (TAMAX), pulsatility index (PI), and resistance index (RI) were measured from intracranial V-BA scanning. RESULTS: Ps, Vd, and TAMAX decreased with age, while PI and RI increased in all groups. Flow velocity in women was slightly higher than that of men, and there was significant differences in group III between men and women (P<.05). However, no difference was found in the flow parameters between left and right vertebral arteries. CONCLUSIONS: This study offered reference values of intracranial V-BA flow parameters in healthy Chinese adults and indicated that these parameters varied with age and gender.     

Sonography of complications in pediatric renal allografts

A total of 420 sonograms of renal transplants in 80 children were obtained because of decreased renal function or to establish a baseline after surgery. We describe normal anatomy of a renal transplant on sonograms, including duplex Doppler and color flow images, and a spectrum of complications. The complications are categorized as follows: parenchymal (drug toxicity rejection, acute tubular necrosis, infection), vascular (pseudoaneurysm, arteriovenous fistula, renal artery stenosis and occlusion), obstructive uropathy, and postoperative fluid collections.     

Duplex Doppler sonography in renal allografts: the significance of reversed flow in diastole

This study was undertaken to assess the significance of diastolic flow reversal seen on duplex Doppler sonograms of patients with renal transplant dysfunction. Earlier studies have evaluated the causes of increased vascular resistance in renal transplants. None, however, have investigated specifically the subset of patients in whom impedance in the renal microcirculation has increased to the degree that retrograde arterial flow is present. In our series, 533 consecutive scans in 270 patients were reviewed. The patients were referred for evaluation of renal transplant dysfunction during a 25-month period. Doppler samples were obtained from main, segmental, and, when possible, arcuate arteries. An episode of reversed diastolic flow was identified in nine patients. Correlation was made with clinical, laboratory, histologic (biopsy in six patients, nephrectomy in three patients), and imaging studies (DTPA scintigraphy in seven patients, angiography in one patient). On the basis of histologic and nephrectomy results, we determined that among the nine patients, four had acute tubular necrosis, three had acute rejection, and two had renal vein thrombosis. One of these patients had both severe rejection and renal vein thrombosis. One additional patient had neither biopsy nor nephrectomy and was not included in the diagnostic groups listed here. Our study suggests that reversed diastolic flow is not specific for either acute rejection or acute tubular necrosis. Reversal of diastolic flow, however, is a poor prognostic sign; nephrectomy was imminent in three of the nine patients. Furthermore, two (22%) patients had renal vein thrombosis, whereas renal vein thrombosis was not found in any of the 261 patients without reversed diastolic flow. Duplex Doppler examinations with reversed diastolic flow should suggest renal vein thrombosis.     

Value of color Doppler ultrasonography in the evaluation of orbital vascular flow in end-stage renal disease patients undergoing hemodialysis

Purpose: To evaluate choroidal and retinal vascular flow dynamics by means of color Doppler ultrasonography in patients with end-stage renal disease undergoing hemodialysis and to compare these findings with healthy controls. Material and Methods: Color Doppler ultrasonography and spectral analysis of nasal and temporal posterior ciliary and central retinal artery flow of both eyes were performed in 20 patients (40 eyes) and 22 controls (44 eyes) to assess peak systolic flow velocity, end-diastolic flow velocity, and resistive indices (RI). Patients with hypertension, diabetes mellitus, and any cardiac pathology were not included in the study. A general ophthalmologic examination was performed in all patients and controls. Results: The average peak-systolic and end-diastolic blood flow velocities of nasal (12.88±4.91/6.88±3.26) and temporal (15.22±9.59/6.41±3.97) posterior ciliary artery and central retinal artery (14.94±8.38/6.7±4.13) in patients were significantly higher than the corresponding values of the controls. The RI values of nasal (0.52±0.10) and temporal (0.58±0.12) posterior ciliary artery and central retinal artery (0.55±0.11) in patients with end-stage renal disease undergoing hemodialysis were significantly lower than in the controls. Conclusion: Choroidal and retinal blood flow velocities are higher and RI values for all three vessels lower in patients with end-stage renal disease undergoing hemodialysis compared to healthy controls. These alterations may be related to either increased choroidal blood flow or vasoconstriction of the proximal vessels.     

彩色多普勒超声显像与能量多普勒超声显像联合定量大脑中动脉血流量初探

目的：探讨彩色多普勒超声显像无创测定大脑中动脉血流量（MCA—BF）及其正常值。方法：采用彩色多普勒超声显像与能量多普勒超声显像联合测定51例正常人大脑中动脉内径（D）和血流速度积分（VTI），根据血流量BF（ml／min）=（D／2）^2π·VTI·HR（HR为心率）计算血流量。结果：应用统计学处理得出正常值。结论：应用彩色多普勒超声血流显像与能量多普勒超声显像可动态测量大脑中动脉血流量，其方法值得深入研究及推广。     

Right carotid artery ligation in neonates: classification of collateral flow with color Doppler imaging

Extracorporeal membrane oxygenation (ECMO) is a lifesaving procedure for neonates that involves permanent ligation of the right common carotid artery. To determine the collateral flow patterns that develop after ligation, 58 infants underwent a total of 115 color Doppler imaging studies during (n = 54), within 1 month after (n = 36), or more than 1 month after (n = 25) ECMO. On the basis of the direction of flow in the right internal carotid artery (ICA) proximal and distal to the right posterior communicating artery (PCoA), 85 of the 115 studies were placed in one of three categories: (a) Anterior communicating artery (ACoA) dominance (n = 22), with retrograde flow in the entire right ICA, was most common during ECMO and was never seen more than 1 month after ECMO. (b) PCoA dominance (n = 47), with antegrade right ICA flow distal to the right PCoA but retrograde proximally, was common during all time periods. (c) External carotid artery (ECA) dominance (n = 16), with antegrade flow throughout the right ICA, was noted in 53% of studies more than 1 month after ECMO but in only 9% of earlier studies. Patterns changed from ACoA to PCoA to ECA dominance in 17 infants, but no change in the opposite direction was noted.