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1.
Lesions of focal nodular hyperplasia are hypervascular, benign focal liver lesions whose differentiation from other focal liver lesions is of significant clinical relevance. The purpose of this study was to investigate the echo-enhancing agent SHU 508A (Levovist) in the evaluation of focal nodular hyperplasia with Doppler sonography. We examined 49 patients with 71 lesions of focal nodular hyperplasia in the liver with gray scale and power Doppler sonography. In all patients Levovist was administered intravenously in a concentration of 300 to 400 mg galactose per milliliter. Visualization of the feeding vessels and the vascularity of the lesions were evaluated, and the resistive indices in the feeders and the hepatic arteries were assessed. In comparison with unenhanced power Doppler sonography, echo-enhanced power Doppler sonography yields a higher sensitivity in the detection of the feeding artery (97% versus 82%) in focal nodular hyperplasia and in the depiction of the radial vascular architecture in such lesions, especially those located in the left lobe of the liver. Lesions less than 3 cm in diameter do not consistently show a characteristic vascular architecture with echo-enhanced Doppler sonography. The resistive index of the tumor-feeding artery (mean, 0.51 +/- 0.09) is significantly (P < 0.0001) lower than that of the hepatic artery (mean, 0.65 +/- 0.06) and decreases as the size of the focal nodular hyperplasia increases. The administration of Levovist may improve the signal-to-noise ratio and thus visualization of the vascular architecture in focal nodular hyperplasia. Lesions located in the left lobe of the liver, which commonly are subject to disturbing motion artifacts in color Doppler sonography, will significantly benefit from the administration of Levovist. Echo-enhanced power Doppler sonography, however, is not capable of depicting a characteristic vascular pattern in small (< or = 3 cm) lesions of focal nodular hyperplasia that would guarantee a specific diagnosis.  相似文献   

2.
Color Doppler sonography has become an integral part of modern hepatic sonography. Color Doppler can enhance the conspicuity of focal lesions and bile ducts in jaundiced patients by illuminating normal vessels with flow. Spectral and color Doppler may prove useful in limiting the sonographic differential diagnosis of focal liver lesions. Color flow sonography effectively evaluates pseudoaneurysms, A-V fistulae, collaterals, and flow reversal in portal hypertension, venous clot and tumor invasion, Budd-Chiari syndrome, hereditary hemorrhagic telangiectasis, and many other hepatic vascular lesions. We have found it invaluable in evaluating cirrhotic and liver transplant patients.  相似文献   

3.
We investigated the diagnostic utility of ultrasonography in the diagnosis of internal jugular venous ectasia. Eight children (six boys, two girls) were recruited into this prospective study. Sonography of internal jugular venous ectasia in these patients revealed fusiform dilation of the internal jugular vein, and the possibility of thrombus and external compression could be ruled out. Marked variation in size of ectatic jugular veins during respiration was demonstrated under real-time sonography. The mean anteroposterior diameter of these dilated internal jugular veins was 0.79+/-0.18 mm (mean+/-standard deviation), which increased to 1.58+/-0.27 mm with Valsalva maneuver. Our study showed that the anteroposterior diameters of the internal jugular veins in cases of ectasia were greater than those of contralateral jugular veins in same patients as well as those in normal children, and they showed greater increase after Valsalva maneuver. Under color Doppler flow studies, turbulent vascular flows were demonstrated in these patients with jugular venous ectasia. No progression of venous ectasia was found in any of our patients during a 6 month follow-up period. We conclude that internal jugular venous ectasia in children is a benign condition, which usually does not require surgical intervention. Ultrasonography is a good diagnostic modality for the diagnosis of internal jugular venous ectasia. Color Doppler ultrasonography demonstrate the turbulent flow in jugular venous ectasia.  相似文献   

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Gallbladder carcinoma: color Doppler sonography   总被引:16,自引:0,他引:16  
This study, based on color Doppler and pulsed Doppler sonographic results of 13 cases with gallbladder carcinoma, eight cases of adenomyomatosis, and eight cases of tumefactive biliary sludge, shows that the presence or absence of blood flow signals helps in the differentiation between gallbladder carcinoma and tumefactive biliary sludge (84.6% sensitivity and 80.0% specificity). However, color Doppler sonography is still not fully capable of distinguishing all gallbladder carcinoma, and a further increase in Doppler sensitivity is mandatory for this purpose. Visualization of high-velocity blood flow within the lesion made gallbladder carcinoma more likely than benign tumor. In contrast, there was no difference in the resistive index between gallbladder carcinoma, adenomyomatosis, and normal subject groups, and the significance of the resistive index is a subject of future study.  相似文献   

6.
Three-dimensional color Doppler sonography was performed within 1 hour, 1 day, 3 months, and 6 months of fibroid embolization in 20 patients who had a total of 31 fibroids greater than 2 cm in average dimension. The greatest decrease in vascularity occurred 1 day after the procedure, whereas the greatest volume change was found at the 3 month follow-up examination. In about one half of the patients scanned, depiction of fibroid vascularity by color Doppler sonography was found to improve the delineation of the size, location, and extent of myometrial involvement. Hypervascular fibroids (12 of 31) tended to decrease in size after treatment more than isovascular (10 of 31) or hypovascular ones (9 of 31). Additional investigations that are similar to this one will be needed to determine if three-dimensional color Doppler sonography can be used to predict those who will be responders, partial responders, or nonresponders to embolotherapy.  相似文献   

7.
Idiopathic intrarenal varices are a rare disease, and only a few cases have been reported. We encountered a patient with intrarenal varices in whom color Doppler sonography was useful for diagnosing and demonstrating this disease, especially with 3D reconstruction of blood flow, which we began using recently.  相似文献   

8.
PURPOSE: The purpose of our study was to evaluate the use of the galactose microbubble-based contrast agent Levovist in color Doppler sonography of uveal melanomas. We also evaluated the use of the resistance index and pulsatility index in differentiating tumor-associated vessels from normal vessels in patients with uveal melanomas. METHODS: In this prospective study, 40 patients with uveal melanoma were examined with color Doppler sonography before and after the administration of the contrast agent Levovist. The Doppler signals were recorded from both the tumor and the orbit and were evaluated quantitatively and qualitatively. RESULTS: Tumor-associated vessels were detected without contrast enhancement in 36 of 40 patients and with contrast enhancement in 38 of 40 patients. The spectral characteristics of the Doppler signals did not change after the injection of Levovist. There were no differences-qualitative or quantitative-in Doppler signals between normal and tumor-associated vessels. CONCLUSIONS: The injection of Levovist slightly improved the detection of small vessels in uveal melanomas and the orbit but did not help to differentiate between normal vessels and tumoral vessels. The differentiation of a solid tumor from subretinal hemorrhage or effusion was improved.  相似文献   

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10.
Sensitivity of color Doppler sonography: an experimental approach.   总被引:3,自引:0,他引:3  
The purpose of this study was to estimate the size required for small vessels to become detectable with color Doppler sonography. A murine experimental tumor was examined with color Doppler sonography after injection of 1.5 mL of the contrast medium Levovist. Histologically, we measured vessel diameters inside the tumor, as well as in its direct neighborhood. With color Doppler at a transmit frequency of 7 MHz, vessels were only detected in the tumor's environment, but not inside. By histology, the 95% quantile of the vessel diameter distribution was found to be 21 microm inside the tumor, 37 microm in the underlying muscle, and 73 microm in the directly adjacent connective tissue. Vessels in the upper range of the size distribution in the muscle and connective tissue are probably detectable. Using the 95% quantile as an estimate, and correcting the values for possible shrinkage, using a factor of 1.91 reported in the literature, vessels in the 74-134 microm range may be detected under the given conditions, whereas vessels measuring 38 microm or less are inaccessible to color Doppler.  相似文献   

11.
We sought to investigate the potential benefit in examining extracranial vertebral arteries (ExVA) with an echo contrast agent. A total of 26 patients with insufficiently assessable ExVA underwent extracranial duplex sonography without and with an echo contrast medium. All examinations were recorded and analysed independently by two experienced sonographers. Interrater agreement was fair in assessment of B-mode quality, colour-coding, blooming artefacts, change of vmax, good to very good in all other rated categories. Using an echo contrast medium reduced overall inassessable ExVA by 48% and 36% according to the two raters, respectively. After contrast enhancement, diagnosis was clarified in ExVA formerly inassessable for hypoplasia in 60% vs. 56%, extracranial occlusion in 67% vs. 56% and resistance signal in 63% vs. 45%, respectively. Application of an echo contrast agent leads to clarification of ExVA sonographic diagnosis in approximately one third of poorly examinable patients (35% and 30%, respectively), and contributes in ruling out extracranial occlusion, hypoplasia and resistance signal.  相似文献   

12.
目的:通过对肺周及肺内实性病灶的彩色信号和多普勒频谱分析,比较良恶性病变的不同表现,探讨彩超在鉴别肺实性病变良恶性方面的价值和方法。资料和方法:1997年3月~2000年12月,经X线或CT定位,B超及彩超共观察肺实性病变107例,其中彩超观察满意的101例为本文研究对象,包括良性38例,恶性63例。有95例经病理证实,包括手术病理17例,穿刺病理68例,支气管镜检8例,痰检2例;另6例炎性病变抗炎治疗后CT证实病灶消失。结果:良性和恶性病变的血流检出率分别为82%和59%,有显著性差异。良性病变动脉峰值流速39.4±28.0cm?s,阻力指数0.71±0.32;恶性病变分别为20.5±20.0cm?s,0.36±0.31。结论:彩超能很好显示肺实性病变内血流状况,对鉴别良恶性病变有重要的参考价值。  相似文献   

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15.
A total of 834 women with uneventful pregnancies were followed prospectively until the 15th week of gestation by TVS to screen for early embryonic malformations. Twenty-eight embryonic anomalies were detected in this series (3.3%). The median gestational age at diagnosis was 11 (range, 8 to 15) weeks. Two neural tube defects were missed by early TVS screening. Two suspected abdominal wall defects were not confirmed by repeat mid-second trimester abdominal sonography representing 6.7% of all fetal malformations evident by 24 weeks of gestation. The sensitivity and specificity of TVS screening for fetal malformations in this series were 93.3 and 99.7%, respectively. In addition, the role of TCDU also was investigated in these 28 abnormal embryos. TCDU proved to be of limited value as it was useful only for evaluating those embryonic malformations with vascular involvement. In such cases, the diagnosis was greatly enhanced with this technique. Two previously undetected single umbilical arteries were also diagnosed by TCDU as well. This series included 11 aneuploid embryos (44%), most of them among the embryos with focal or generalized edema. This study demonstrates that screening for early embryonic malformations is feasible using TVS techniques, but a repeat mid-second trimester abdominal sonogram still is recommended.  相似文献   

16.
经阴道彩色多普勒超声在子宫内膜癌诊断中的应用   总被引:3,自引:1,他引:3  
目的:探讨经阴道彩色多普勒超声对子宫内膜癌的诊断价值。方法:采用TVCDS检查子宫内膜癌15例,观察内膜血流情况及用PD(频谱多普勒)检测病变区血流速度,测得RI值。结果:子宫内膜内彩色血流信号异常丰富,呈现低阻力血流,RI=0.35 0.05。结论:经阴道彩色多普勒超声具有高分辨特征,并能提供高敏感性的血流信息,对子宫内膜癌诊断有重要价值。  相似文献   

17.
Eleven cases of mumps epididymo-orchitis were examined by gray-scale and color Doppler ultrasonography. Nine cases were unilateral and two were bilateral. In the initial examination, the volume and the vascularity of the affected testis and epididymis and the thickness of the scrotal wall was greater than of the normal site, whereas the testicular echogenicity was decreased homogenously, resistivity indexes of intratesticular arteries were decreased, and spontaneous venous flow was seen in all cases. In contrast to nonspecific epididymo-orchitis, no hydrocele was seen, but minimal reactive hydrocele was found in two cases. The diagnosis was confirmed by specific immunoglobulin-G examination. Patients were given interferon and were controlled by ultrasonography and Doppler ultrasonography at the third and seventh days of treatment and 3 months after treatment. Sonographic findings began to improve by the third day and fully disappeared in seventh day. No testicular atrophy was seen in the last control. To our knowledge, this is the first report on sonographic and color Doppler sonographic findings of mumps epididymo-orchitis.  相似文献   

18.
We report the use of color Doppler imaging in the diagnosis of four arteriovenous fistulas in the neck region: two had a traumatic origin and two were spontaneous. A perivascular color artifact was the most common initial finding on color images to indicate the underlying abnormality. In all four cases, a low-resistance flow with high systolic and diastolic velocities was observed in the feeding artery. Although angiography remains essential before therapeutic embolization, color Doppler sonography may be an important tool for screening and follow-up of cervical arteriovenous fistulas.  相似文献   

19.
Liver involvement with hereditary hemorrhagic telangiectasia (HHT) is not a rare condition. Its angiographic abnormalities are well known, but reports of the sonographic and, especially, color Doppler sonographic findings are limited. We present a patient with HHT and describe the hepatic color Doppler sonographic findings. Received: 0/0/00/Accepted: 0/0/00  相似文献   

20.
Quantified color Doppler sonography of tumor vascularity in an animal model.   总被引:10,自引:0,他引:10  
This study was designed to evaluate the accuracy of a system to quantitate tumor vascularity with amplitude (power) color Doppler sonography two- and three-dimensionally. The vascularity of 20 transplanted murine tumors was determined with quantitated amplitude color Doppler sonography both two- and three-dimensionally and compared to tumor vascularity estimated by histologic examination. Serial examinations were performed 15, 30, 45, and 60 min after the injection of the exotoxin CM-101 and saline solution to assess changes in tumor vascularity. Three-dimensional amplitude color Doppler sonography best depicted the overall vascularity of tumor when compared to histologic estimation of vessel density. However, neither two- nor three-dimensional amplitude color power angiography correlated well to the microvessel count, probably a reflection of the difference in the method for vessel quantification using sonographic versus histologic techniques. Three-dimensional amplitude Doppler sonography correlated better with counts of large vessels (> 100 microm) as opposed to small vessels (> 15 microm). Time-activity curves showed no difference in tumor flow at the times measured in the experimental group injected with CM-101 or when compared to saline solutions in either the peripheral or central portions of the tumor. This three-dimensional amplitude color Doppler sonographic system affords global quantification of tumor vascularity and flow that may, in turn, be useful in determining the probability of malignancy (by determination of branching patterns and vessel regularity) or tumor response or both to treatment.  相似文献   

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