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1.
《中国现代医生》2020,58(19):119-122+封三
目的 探讨实时超声引导微波消融术治疗子宫腺肌瘤的临床应用。方法 选取2015年1月~2019年1月收入我院子宫腺肌瘤患者37例为研究对象。采用超声造影评价患者的腺肌瘤消融率,常规超声评价瘤体缩小率。采用临床疗效评定标准来评价患者临床症状改善情况。结果 痛经改善率为78.9%(15/19),月经失调改善率为42.9%(9/21),贫血改善率为55.6%(10/18)。超声造影显示仅3例出现消融不完全,消融有效率为91.9%,术后行补充消融治疗,37例局限性子宫腺肌瘤平均消融率均达90%以上。与治疗前比较,治疗后3、6、12个月患者瘤体缩小率分别为60.8%、78.1%、93.1%,差异有统计学意义(P0.05)。与治疗前比较,治疗后临床症状有改善。结论实时超声引导微波消融术治疗子宫腺肌瘤患者,能够减小腺肌瘤体积,且能够明显改善患者临床症状,为子宫肌瘤患者提供新的治疗手段。  相似文献   
2.
We prospectively evaluated the effectiveness of contrast-enhanced ultrasonography (CEUS) for differentiation of benign versus malignant portal vein thrombosis (PVT). We studied a total of 43 patients with chronic liver disease, hepatocellular carcinoma-suggestive nodules and confirmed PVT, in whom the nature of the PVT was confirmed by follow-up imaging (US, computed tomography and/or magnetic resonance imaging) performed up to 6 mo after CEUS. PVT was assessed by US, Doppler US and CEUS with respect to vessel wall disruption and/or invasion, color Doppler vascularization, pulsed Doppler vascularization pattern and CEUS enhancement and vascularization pattern, and thrombi were classified as benign or malignant based on these findings. Follow-up studies revealed malignant PVT in 22 of the 43 patients (51%) and benign PVT in 21 patients (49%). CEUS findings were consistent with follow-up studies in 41 of the 43 patients (95%), with κ?=?0.903 (p < 0.0001), sensitivity?=?91% and specificity?=?100%, indicating that CEUS can be confidently used to differentiate benign from malignant portal vein thrombosis in the setting of chronic liver disease.  相似文献   
3.
Objective: To investigate the ability of contrast enhancement patterns of contrast-enhanced ultrasound in differentiating benign and malignant soft tissue tumours.  相似文献   
4.
Gross hemorrhage is the most serious complication of anticoagulant therapy. We report the discovery and treatment of a large pseudoaneurysm of the superior gluteal artery in one patient who had been receiving oral anticoagulant therapy. We diagnosed the pseudoaneurysm by contrast-enhanced computed tomography, and embolized the artery with stainless steel coils. The exact cause of the pseudoaneurysm remains unclear, however, minor trauma appears most likely.  相似文献   
5.
Summary The introduction of fast gradient systems allows a reliable visualization of the extracranial carotid vessels by the magnetic resonance angiography (MRA) which meanwhile is implemented into clinical routine. By the mainly applied time-of-flight (TOF) technique, vessels can be imaged without contrast agent (CA). Due to the application of ultra-fast gradient-echo-sequences, the first-pass evaluation of an intravenous bolus-injection of Gadolinium in the carotids from the aortic arch up to the skull base can be performed in less than 30 s. In this study, advantages and disadvantages of both techniques are discussed. For a qualitatively optimal contrast enhanced MRA (CE-MRA) timing parameters like injection delay, flow rate and the adjustment of sequence parameters have to be considered in relation to the fast venous return from the sinus to the jugular veins. First, the optimal time point of the data acquisition have been determined at a model and with a computer simulation in reference to the presence of CA in the arteries. As a result, 90 % of the contrast contribution is defined by 16 % of the symmetrically acquired central k-space lines. A measuring protocol for clinical use was obtained by a gradual variation of spacial resolution, measuring time and CA-injection parameters and was proved in normal volunteers and patients. An exact determination of the bolus-arrival-time by means of a test-bolus injection was acquired. The best qualitative results were achieved by a double-dose injection at 2 ml/s injection rate. The temporal reserves of ultra-fast sequences should be invested in the improvement of the spatial resolution. To date, further investigations related to the problem of optimal CA-application may improve the potentials of CE-MRA procedures.   相似文献   
6.
In the past few years magnetic resonance angiography (MRA) of the pulmonary vasculature has advanced from a research tool to a clinically relevant imaging modality. Early 2D phase-contrast and time-of-flight (TOF) sequences without the use of contrast agents were time-consuming and limited by considerable imaging and motion artifacts. Since the introduction of MR scanners with stronger gradients (> 20 mT/m) and contrast-enhanced techniques, imaging of the pulmonary vasculature with adequate spatial resolution within a single breathhold is now possible. In the detection of pulmonary embolism in the lobar or segmental arteries, contrast-enhanced MRA is now on the verge of being considered an established modality, possibly competing with conventional pulmonary angiography and contrast-enhanced helical CT. In the future, utilization of phased-array torso coils, the application of navigator pulse sequences, and 3D time-resolved ultrafast MRA will overcome the final limitations of current techniques. Blood-pool MR contrast agents may provide a “one-stop-shopping” approach to the investigation of lower extremity veins and pulmonary arteries in venous thromboembolism.  相似文献   
7.
A phantom consisting of four components was developed to simulate contrast-enhanced MR imaging of the breast. These components included the correlation between the signal intensity and the contrast medium concentration, the uniformity of signals within surface coils, artefacts due to opposed-phase imaging effects, spatial resolution and the acquisition of relevant signal-to-time curves. Repetitive measurements demonstrated an excellent reproduction of phantom imaging with a deviation in signal intensity of approximately 5 %. The presented phantom allows the optimization of examination protocols as well as the comparison of different examination techniques. Furthermore, it enables the routine quality monitoring of contrast-enhanced MR imaging of the breast. Received: 28 May 1998; Revised: 3 September 1998; Accepted: 14 October 1998  相似文献   
8.
The mean gray-scale ratio of the infiltrating zone of a lesion to the surrounding normal liver tissue was evaluated on the basis of contrast enhancement of the infiltration and proliferation zones of a hepatic alveolar echinococcosis lesion. The results were compared with the maximum standardized uptake value (SUVmax) of [18F]fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET-CT), and the application of contrast-enhanced ultrasound in evaluating hepatic alveolar echinococcosis activity is discussed. The 36 patients with hepatic alveolar echinococcosis recruited underwent contrast-enhanced ultrasound and [18F]FDG PET-CT. A total of 39 lesions were found in the 36 patients. The results indicated that in 87.2% of the cases, the two methods yielded the same diagnosis, whereas in 12.8% of cases, the diagnoses obtained with the two methods were inconsistent. The statistical results revealed that contrast-enhanced ultrasound and [18F]FDG PET-CT have good inter-rater reliability in determining the activity of hepatic alveolar echinococcosis (κ?=?0.756, p < 0.01).  相似文献   
9.
Bile duct ligation (BDL) can cause cholangitis, which is known to induce impaired Kupffer cell (KC) function and increased oxygen consumption in a mouse model. It is important to monitor changes in KC function and tissue oxygen saturation, both of which are critical factors in the progression of cholangitis. The purpose of this study is to investigate the impaired phagocytic activity of KC and liver oxygen saturation (sO2) in a mouse cholangitis model using contrast-enhanced ultrasound imaging (CEUS) and photoacoustic imaging (PAI). A mouse cholangitis model was created by ligation of the common bile duct (CBDL, n = 20), and the left intrahepatic bile duct (BDL-L, n = 19), both of which were compared with the non-ligation groups—right lobe measurement group after left intrahepatic bile duct ligation (BDL-R, n = 19) and the control group (n = 14). The echogenicity and sO2 were measured by CEUS and PAI and the KC fraction was assessed at 1, 2 and 4 wk after ligation. We found a significantly lower echogenicity of the Kupffer phase in the CBDL and BDL-L groups compared with that in the control and BDL-R groups at 2 wk (p < .01). The CBDL and BDL-L groups showed a lower echogenicity than that of the BDL-R group at 4 wk (p < .01). We found a significantly lower sO2 of the CBDL and BDL-L groups compared with that of the control and BDL-R groups at 4 wk (p < .01). The CBDL and BDL-L groups showed a higher KC fraction than that of the BDL-R and control groups at each time point (p < .01). In conclusion, our study suggests that the Sonazoid CEUS and PAI could be a useful tool for monitoring impaired KC phagocytic activity and the liver hypoxic state.  相似文献   
10.
《中国现代医生》2017,55(33):95-98,封3
目的采用多模态超声对HBV相关肝硬化背景内结节进行评估并分类。方法选取2013年10月~2016年10月于浙江中医药大学附属杭州市西溪医院就诊的HBV相关性肝硬化患者200例,其中病理诊断为增生结节(RN)者51例,不典型增生结节(DN)者57例,其中低级别不典型增生结节(LGDN)27例,高级别不典型增生结节(HGDN)30例,肝细胞肝癌(HCC)为17例,均行多模态二维超声、彩色多普勒、超声造影检查,对比不同病理类型的结节多模态超声特征性表现,进一步将肝硬化背景肝内结节分为Ⅰ、Ⅱ、Ⅲ、Ⅳ4类。采用χ~2检验比较不同大小、超声造影不同增强模式肝硬化背景肝内DN及HCC检出率的差异。结果直径2.0~3.0 cm结节25个,均为HCC与DN;直径1.0~2.0 cm结节94个,4个为HCC,24个为HGDN;直径1.0 cm结节6个,全部为RN;不同大小肝硬化背景肝内结节HCC与DN检出率差异有统计学意义(P0.05)。RN结节主要以"等进等出"增强模式为主,LGDN主要以"慢进等出"增强模式为主,HGDN及HCC主要以"快进快出"增强模式为主,不同组间不同的增强模式差异有统计学意义(P0.05);而HCC与HGDN在造影剂进入时间、达峰时间、流出时间上差异有统计学意义(P0.05),Ⅲ类、Ⅳ类结节在DN及HCC检出率上差异有统计学意义(P0.05)。结论多模态超声对于HBV相关肝硬化肝内结节进行评估、分类,对于HGDN及HCC早期诊断有一定帮助。  相似文献   
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