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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.  相似文献   

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Twenty-one tumors in 20 children were evaluated with duplex and color Doppler imaging to determine the value of the technique in assessing the origin and pattern of vascular supply and the degree of neovascularity. The origin of the vascular supply was detected correctly in 12 of 13 tumors that were subsequently resected. In five children, this aided in determining the organ from which the tumor originated, and in one child, it established the presence of a tumor by showing blood flow in the center of a suspected abscess. In 18 tumors, color Doppler imaging showed the pattern of the vascular supply. Eleven had a peripheral pattern, and seven had a central, branching pattern. Although individual tumor types appeared to have characteristic patterns of vascular supply, these were not specific enough to aid in making a specific diagnosis. When the degree of intratumor neovascularity was graded on the basis of the findings on color Doppler imaging, it agreed with the results of histologic evaluation in 16 of 19 tumors. In one tumor, neovascularity was overestimated, and in two, it was markedly underestimated. Our experience suggests that color Doppler imaging is useful in detecting the origin and pattern of vascular supply and the degree of intratumoral blood flow in a variety of solid tumors in children.  相似文献   

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目的 :探讨彩色多普勒能量图检测浅表淋巴结内动脉血流在鉴别良恶性淋巴结病变的价值。方法 :回顾性分析 12 6例浅表淋巴结病变的彩色多普勒能量图及动脉血流频谱。其中良性淋巴结肿大 33例 ;恶性淋巴瘤 18例 ;淋巴结转移性肿大 75例。均经穿刺活检或手术病理证实。结果 :110个 (87.3% )淋巴结内检出动脉血流频谱 ,血流检出率良性病变为 72 .7% (2 4 / 33) ,恶性肿瘤为 92 .5 % (86 / 93)。良性肿大组、恶性淋巴瘤组和淋巴结转移癌组淋巴结内动脉血流PSV分别为 14 .4± 7.3cm/s、2 0 .1± 7.9cm/s和 18.2± 5 .1cm/s,RI测值分别为 0 .6 2± 0 .0 9、0 .73± 0 .19和 0 .74± 0 .16。t检验结果 ,淋巴结内动脉血流速度 (PSV)和阻力指数 (RI) ,良性疾病与恶性淋巴瘤和淋巴结转移癌组间差异具显著性 ,恶性淋巴瘤组和转移癌组间差异无显著性。结论 :淋巴结内动脉血流RI值可作为鉴别淋巴结良恶性的一个重要指标。但是 ,良恶性病变间PSV、RI值存在一定重叠。  相似文献   

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The ability of transcranial pulsed Doppler ultrasound (TCD) to provide a dynamic assessment of the functional capability of the Circle of Willis was assessed using conventional cerebral angiography for anatomic correlation. Eleven patients had normal four-vessel cerebral angiography prior to being investigated with ultrasound. Angiography and ultrasound both demonstrated a functional anterior communicating artery in nine of the eleven patients, giving complete agreement between the two techniques. Posterior communicating arteries were visualized angiographically in all eleven patients. Ultrasound identified bilateral functional vessels in nine, the other two patients having non-functional vessels. In these latter two patients, angiography demonstrated three of the four posterior communicating arteries to be hypoplastic and it was uncertain whether these vessels carried significant blood flow. The fourth posterior communicating artery was shown to have an absent proximal segment of the ipsilateral posterior cerebral artery, with a persistent fetal posterior communicating artery. This anatomical variation is a potential limitation of ultrasound for assessing functional posterior communicating arteries. These preliminary results indicate that a combination of the anatomical (angiographic) and dynamic (ultrasonic) data may prove to be complementary for assessing the Circle of Willis.  相似文献   

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Polyorchidism, the presence of more than two testes, is a very rare anomaly. We report the color Doppler ultrasonography and magnetic resonance imaging findings of the case of a 20-year-old man with polyorchidism, presenting with an asymptomatic scrotal mass. Ultrasonography showed double testes with double separate epididymides sharing a common vas deferens in the left side of the scrotum. The double testes demonstrated similar echo texture and vascular flow as the normal testis, but smaller in size. Magnetic resonance imaging showed three testes very clearly and confirmed the diagnoses. After 2 years of follow-up, he was managed with surgical intervention. Pathology report revealed polyorchidism.  相似文献   

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Budd-Chiari syndrome: the results of duplex and color Doppler imaging   总被引:3,自引:0,他引:3  
This study was designed to evaluate duplex and color-flow Doppler imaging as potential noninvasive methods of diagnosing patients with Budd-Chiari syndrome and following them after surgery. Five patients with confirmed hepatic venoocclusive disease were imaged. All five underwent duplex Doppler examinations; three were also evaluated with color-flow Doppler. The hepatic vasculature was examined in all five patients; decompressive mesoatrial shunts were present and were evaluated in four of the five patients. Color-flow Doppler precisely defined intrahepatic, portal, and inferior vena caval circulatory dynamics. Correlation with angiography was excellent. In the two patients in whom hepatic vasculature was evaluated with duplex Doppler alone, the results were less impressive. Intrahepatic flow abnormalities were identified, but the sites of occlusion were not determined convincingly. Signals transmitted from the heart and the inability to visualize the hepatic veins made duplex Doppler evaluation problematic. Duplex Doppler was able to define patency and the direction of flow in the portal vein and inferior vena cava. Our results suggest that color-flow Doppler is an excellent technique for the initial evaluation of patients suspected of having Budd-Chiari syndrome. In the evaluation of decompressive mesoatrial shunts, color-flow Doppler produced dramatic images. However, both duplex and color-flow Doppler were highly accurate in determining the patency of decompressive shunts. Either duplex or color-flow Doppler may be used as the primary imaging procedure to determine shunt patency.  相似文献   

10.
S Jequier  H Paltiel  M Lafortune 《Radiology》1990,175(2):349-353
Ureteric jets were studied with conventional duplex Doppler (79 patients) and with color Doppler flow imaging (22 patients). Correlation with voiding cystourethrography (VCUG), performed ont he same day, was obtained in all patients. Thirty-six patients with normal VCUG results and normal renal and bladder ultrasound (US) studies served as the control group for 39 patients with vesicoureteric reflux (VUR) and 26 patients with urinary tract disorders other than reflux. The site of the ureteric orifice and duration, direction, and turbulence of the jets were recorded. Duration varied from 0.4 sec to 7.5 sec and depended largely on fluid intake. Duration varied in an individual patient by up to 2 sec from one jet to another. The direction of the normal jet was anteromedial and upward. Jets from refluxing ureters can appear normal. Severe renal parenchymal scarring reduced frequency and amplitude of the jets. Doppler analysis of the ureteric jet does not allow diagnosis or exclusion of VUR. Color Doppler was more sensitive in demonstrating ureteric jets than was gray-scale, real-time US and facilitated the study, but it was equally unable to help predict reflux.  相似文献   

11.
目的应用组织多普勒成像技术(TDI)评价早产儿及足月儿右心室Tei指数的改变,并与传统血流多普勒的测量方法比较,为临床评估右心室功能及治疗提供依据。方法对100名新生儿中早产儿和足月儿各50名进行两种多普勒超声心动图技术测定右心室等容收缩期(ICT)与等容舒张期时间(IRT)之和(ICT+IRT)及射血时间(ET),并计算Tei指数。结果血流多普勒与组织多普勒两种方法测得的早产儿右心室Tei指数均高于足月儿,差异有统计学意义(P<0.01);且所有受检新生儿的组织多普勒图像较传统血流多普勒图像清晰易辨认,两种方法测量结果差异无统计学意义(P>0.05)。结论早产儿右心室功能低于足月儿,组织多普勒可取代传统方法测量Tei指数,是评估新生儿特别是早产儿右心功能的一种简便而敏感的方法。  相似文献   

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Five neonates with cranial arteriovenous malformations were studied with color Doppler sonography. Excellent correlation was found between sonography and subsequent angiography. In three patients with vein of Galen aneurysms, sonography showed a cystic structure with rapid or swirling flow. Careful adjustment of the color Doppler system was required to demonstrate flow in another patient with a dural arteriovenous malformation. An arteriovenous fistula in a fifth patient appeared as an area of increased flow. Arterial feeders and major draining veins were visualized in all five patients. Color Doppler imaging also was used to assess the effect of embolic or operative therapy in three of the patients. We conclude that color Doppler sonography is able reliably to characterize flow patterns in neonatal cranial arteriovenous malformations. Color Doppler imaging also is helpful in assessing flow after embolic or surgical therapy.  相似文献   

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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.  相似文献   

15.
Diagnosis of portal vein thrombosis: value of color Doppler imaging.   总被引:10,自引:0,他引:10  
This study was undertaken to determine the accuracy of color Doppler imaging in the diagnosis of portal vein thrombosis. Two hundred fifteen patients were studied with color Doppler imaging to determine patency of the main portal vein. Sonographic findings were confirmed in 75 patients, aged 19 to 66 years. Correlation with angiography was obtained in 13 patients, and surgical correlation was obtained in the remaining 62. Nine patients had portal vein thrombosis on the basis of these gold standards. Sonograms were classified as showing either patency or thrombosis, depending on the ability to show color flow within the main portal vein. Agreement between sonography and angiography or surgery was found in 69 patients (61 patent, eight thrombosed). One patient with a patent portal vein at sonography was found to have a thrombosed vessel at surgery, whereas five patients without portal venous flow at sonography had patent vessels at angiography (one patient) or surgery (four patients). Overall sensitivity and specificity for detection of portal vein thrombosis were 89% and 92%, with an accuracy of 92%, a false-negative rate of 0.11, a negative predictive value of 0.98, and a positive predictive value of 0.62. We postulate that the majority of errors in our study occurred in vessels that, although patent, had only sluggish flow, which could not be resolved because of technical limitations. We conclude that color Doppler imaging is a valuable screening procedure for the assessment of portal vein patency. If the sonogram shows a patent portal vein, no further studies are required. However, a lack of demonstrable flow does not always indicate thrombosis, and other imaging studies should be performed for confirmation.  相似文献   

16.
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.  相似文献   

17.
OBJECTIVE: B-flow imaging is a non-Doppler technology that provides real-time imaging of blood flow during gray-scale sonography. The utility of B-flow imaging is reflected in numerous publications that describe normal and pathologic findings in the carotid arteries and hemodialysis fistulas. However, there is a paucity of articles describing B-flow imaging of the abdominopelvic viscera. The purpose of this article is to illustrate a spectrum of findings encountered during noninvasive flow evaluation of the hepatic vasculature, correlating the Doppler sonography and B-flow imaging findings. CONCLUSION: Color and spectral Doppler sonography are invaluable for noninvasive evaluation of the hepatic vasculature. However, a number of pitfalls and artifacts have been described that can cause important pathologic findings to be overlooked or can suggest incorrect diagnoses. In our experience, B-flow imaging often correctly displays normal and pathological vascular structures for which Doppler sonographic findings have been misleading or erroneous.  相似文献   

18.
Polak  JF; Culter  SS; O'Leary  DH 《Radiology》1989,171(2):481-485
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.  相似文献   

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Middleton  WD; Foley  WD; Lawson  TL 《Radiology》1988,167(1):207-210
One hundred carotid bifurcations in young asymptomatic volunteers were examined with color Doppler flow imaging in an attempt to determine the frequency, configuration, magnitude, and duration of flow reversal. Areas of flow reversal were identified in all but one bifurcation. Just proximal to the bifurcation, flow reversal was typically located peripherally, opposite the origin of the external carotid artery. Distal to the bifurcation, flow reversal in the internal carotid artery typically assumed a linear configuration in the center of the vessel, extending from the superficial to the deep wall. Variations of these patterns were common. On the average, flow reversal occupied 33% of the lumen of the carotid bulb and extended for a distance of 14 mm. The average duration of flow reversal was 22% of the total cardiac cycle, with reversal typically occurring at peak systole and being replaced by static blood during diastole. These findings indicate that flow reversal in the carotid bifurcation is a normal phenomenon with a variable configuration, magnitude, and duration.  相似文献   

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