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1.
Paragangliomas are extra-adrenal pheochromocytomas that derive from chromaffin cells and arise along the sympathetic paraganglia in the body. In the majority of cases, they are secretory tumors and most commonly present with palpitations. Plasma metanephrines are the standard screening tests for making the diagnosis which is confirmed by pathology. Imaging plays a very important role in establishing the diagnosis. However, there is no specific feature on imaging for paragangliomas; the vascularity of the tumor should show as hyper-enhancing lesions but this is not always the case. The diagnostic value of PET is yet a matter of debate. We present a very rare case of a paraganglioma arising at the renal hilum, splaying the renal artery and vein and causing vascular compromise to the left kidney. The patient presented with an atypical presentation of unrelenting fever that was followed by acute colicky pain. Based on imaging and blood metanephrine levels, the diagnosis of paraganglioma was made. Resection of the tumor was achieved and the patient is now asymptomatic.  相似文献   

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Since the National Institute of Neurological Disorders and Stroke trial, intravenous thrombolysis has been gaining wide acceptance as the modality of treatment for acute embolic stroke, with a current therapeutic window of up to 4.5 h. Both imaging [with either magnetic resonance imaging (MRI) or computed tomography (CT)] and interventional techniques (thrombolysis and/or thrombectomy) have since improved and provided us with additional imaging of the penumbra using CT or MRI and more advanced thrombolysis or thrombectomy strategies that have been embraced in many centers dealing with patients with acute cerebral ischemia. These techniques, however, have come under scrutiny due to their accrued healthcare costs and have been questioned following major recent studies. These studies basically showed that interventional techniques were not superior to the traditional intravenous thrombolysis techniques and that penumbra imaging could not determine what patients would benefit from more aggressive (i.e., interventional) treatment. We discuss this in the light of the latest developments in both diagnostic and interventional neuroradiology and point out why further studies are needed in order to define the right choices for patients with acute stroke. Indeed, these studies were in part conducted with suboptimal patient recruitment strategies and did not always use the latest interventional techniques available today. So, while these studies may have raised some relevant questions, at the same time, definitive answers have not been given, in our opinion.  相似文献   

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患者,男性,58岁,以“十二指肠球部息肉”收住入院。患者于2年前无明显诱因出现上腹部饱胀不适,餐后尤甚,无反酸、烧灼,无呃逆、嗳气,无腹痛及放射痛,无恶心、呕吐,无腹泻及黑便,无黄疸等症状。入院行电子胃镜检查示十二指肠球部息肉。超声内镜检查:十二指肠球部后壁可见一直经约4.0 cm带蒂隆起,表面呈“分叶状”,光滑,球部腔内狭窄,降部未见异常。临床诊断:十二指肠球部息肉;慢性萎缩性胃炎(Ⅰ级)。  相似文献   

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Toll样受体(Toll like receptors, TLRs)为一种跨膜转导蛋白,主要表达于淋巴细胞及某些上皮细胞表面,通过识别体内、外特异性配体而激活机体免疫应答。由此可见,TLRs信号激活本是机体防御的第一道防线,但如果其信号过度活化则可打破机体对自身抗原的免疫耐受而导致自身免疫性疾病的发生。本文综述了TLRs的种类、配体及相应的信号通路,主要探讨了TLRs与自身免疫性疾病的关系及治疗前景。  相似文献   

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番荔枝科暗罗属植物在我国南方地区分布较多,民间习惯作为抗菌、退热药等使用,已经从该属植物中分离出生物碱、萜类、内酯等活性成分。本文综述了国内外学者近年来对暗罗属植物生物活性研究,包括抗氧化、抗肿瘤、抗菌、抗病毒、抗寄生虫、抗炎作用等,为进一步深入研究、开发和利用我国的暗罗属植物资源提供数据支持。  相似文献   

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Contrast-enhanced ultrasound (CEUS) is one of the important imaging modalities for diagnosis of hepatocellular carcinoma (HCC). Sonovue and Sonazoid are the third-generation of ultrasound contrast agents that have been commercialized and widely used in clinical applications. This study introduces the imaging differences between these two agents in vascular phases for the first time. A 54-year-old man clinical suspected liver cancer. He had chronic hepatitis B for more than 20 years. The result of alpha-fetoprotein was 36.45μg/L (normal< 20μg/L). The imaging pattern of CEUS with Sonovue was “fast-in and fast-out” performance, while the pattern of “fast-out” was absent after portal phase with Sonazoid, even in Kupffer phase. The lesion was diagnosed as lipid-rich HCC by contrast-enhanced MRI. After liver resection, pathology revealed that it was hepatocellular carcinoma contained poor-differentiated steatohepatitis subtype and moderate-differentiated microtrabecular subtype. The imaging difference mainly existed in the part of steatohepatitis subtype. Steatohepatitis subtype HCC can be showed as “fast-in and no wash-out” characteristic in Sonazoid CEUS. Though the mechanism remains not fully clarified, this different enhancing pattern may provide a potential for the supplement of the guidelines and differential of steatohepatitis subtype HCC.  相似文献   

12.
Focal liver lesions: role of contrast-enhanced ultrasound   总被引:2,自引:0,他引:2  
The introduction of microbubble contrast agents and the development of contrast-specific techniques have opened new possibilities in liver imaging. Initially, only intermittent imaging with Doppler detection was available. Second-generation contrast agents and low mechanical index real-time scanning techniques are decisive advances that enable convenient liver examinations with high sensitivity and specificity. Hepatic lesions usually show typical perfusion and enhancement patterns through the various contrast phases, which help their characterization. Several published studies and the daily clinical routine show that, as opposed to conventional ultrasound (US), contrast-enhanced US can substantially improve detection and differentiation of focal liver lesions. Today, contrast-enhanced US is the dynamic imaging modality of choice for differentiation of focal liver lesions. Contrast uptake patterns of the most relevant liver lesions, as well as important clinical indications are presented and discussed.  相似文献   

13.
The purpose of this study was to evaluate the detection rate of tumor vessels and vascularity in hepatocellular carcinoma (HCC) by contrast-enhanced coded US using Levovist, and to compare with conventional color/power Doppler US (CDUS) and dynamic CT. Ninety nodules (72 hypo/isoechoic nodules, 18 hyperechoic nodules) in 61 patients were studied. We observed tumor vessels by continuous transmission at the early vascular phase (40 s following administration of Levovist) and vascularity by intermittent transmission (intervals of 2–3 s) at the late vascular phase (40 to approximately 120 s). The detection rate of tumor vessels at the early vascular phase was 97% in hypo/isoechoic nodules and 70% in hyperechoic nodules with high density in dynamic CT being higher than that by CDUS. Tumor vascularity at the late vascular phase in hypo/isoechoic and hyperechoic nodules was hyper-enhancement in 78 and 40%, iso-enhancement in 19 and 40%, and hypo-enhancement in 3 and 0%, respectively. The detection rates of tumor vessels and vascularity in hyperechoic nodules were similar to those by CDUS. The detection rates of tumor vessels and vascularity were not affected by the tumor size in HCC tumors with high density in dynamic CT. Contrast-enhanced US with Levovist was superior to CDUS and equal to dynamic CT to assess tumor vessels in hypo/isoechoic nodules. Although it was equal to CDUS for hyperechoic nodules, this modality is useful in evaluating tumor hemodynamics.  相似文献   

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目的探讨超声造影参数成像分析在肝细胞肝癌(HCC)诊断中的应用价值。方法分析68例HCC的超声造影资料,应用SonoLiverR CAP定量分析软件,以HCC与周围肝实质的增强水平差值为参数进行动态血管模型(dy-namic vascular pattern,DVP)重建,分析结果以DVP彩色编码图、DVP曲线图及定量参数显示,并进行分型及统计学分析。结果 DVP彩色编码图:消退型,未消退型分别占88.24%(60/68)和11.76%(8/68);DVP曲线图:消退型,未消退型分别占83.82%(57/68)和16.18%(11/68)。定量参数显示HCC与周围肝实质的峰值强度、上升时间、达峰时间和平均渡越时间的差异均具有统计学意义(P<0.05)。结论超声造影参数成像可直观、量化的显示病灶变化,为HCC诊断提供更为准确的定量信息。  相似文献   

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The appearance of hepatocellular carcinoma (HCC) with contrast-enhanced ultrasound (CEUS) in the vascular phase is described and evaluated as to whether the enhancement pattern correlates with the degree of cellular differentiation. One hundred four HCCs were prospectively evaluated with CEUS using coherent-contrast imaging (CCI) and SonoVue with a low mechanical index (<0.2). The enhancement of HCCs in the vascular phase was analyzed according to the degree of pathological differentiation obtained by fine-needle biopsy. In the arterial phase, all HCCs except for four well differentiated ones (96.2%) showed enhancement (P<0.05). Histological differentiation of hypoechoic lesions in the early portal phase (7 HCCs; 16%) significantly differed from hyperechoic (1 HCC; 1%) or isoechoic lesions (87 HCCs; 83.6%) (P<0.05), with a significant probability of a worse differentiation in hypoechoic lesions. Histological differentiation of isoechoic lesions in the late phase (30 HCCs; 28.8%) significantly differed from hypoechoic lesions (74 HCCs; 71.2%) (P<0.05), with a significant probability of a better differentiation in isoechoic lesions. CEUS using CCI and SonoVue revealed enhancement in the arterial phase in >95% of HCCs, with a few well-differentiated cases not being diagnosed due to the absence of enhancement. Echogenicity in the portal and late phases correlated with cellular differentiation.  相似文献   

16.
AIM: To assess the role of contrast enhanced ultrasonography in evaluation of hepatocellular carcinoma (HCC) at the first Indian tertiary liver center. METHODS: Retrospective analysis of contrast enhanced ultrasound (CEUS) examinations over 24 mo for diagnosis, surveillance, characterization and follow up of 50 patients in the context of HCC was performed. The source and indication of referrals, change in referral rate, accuracy and usefulness of CEUS in a tertiary liver center equipped with a 64 slice dual energy computer tomography (CT) and 3 tesla magnetic resonance imaging (MRI) were studied. Sonovue (BR1, Bracco, Italy, a second generation contrast agent) was used for contrast US studies. Contrast enhanced CT/MRI or both were performed in all patients. The findings were taken as a baseline reference and correlation was done with respect to contrast US. Contrast enhanced MRI was performed using hepatocyte specific gadobenate dimeglumine (Gd-BOPTA). Iomeron (400 mg; w/v) was used for dynamic CT examinations. RESULTS: About 20 (40%) of the examinations were referred from clinicians for characterization of a mass from previous imaging. About 15 (30%) were performed for surveillance in chronic liver disease; 5 (10%) examinations were performed for monitoring lesions after radiofrequency ablation (RFA); 3 (6%) were post trans-arterial chemoembolization (TACE) assessments and 3 (6%) were patients with h/o iodinated contrast allergy. About 2(4%) were performed on hemodynamically unstable patients in the intensive care with raised alpha fetoprotein and 2(4%) patients were claustrophobic. The number of patients referred from clinicians steadily increased from 12 in the first 12 mo of the study to 38 in the last 12 mo. CEUS was able to diagnose 88% of positive cases of HCC as per reference standards. In the surveillance group, specificity was 53.3% vs 100% by CT/MRI. Post RFA and TACE specificity of lesion characterization by CEUS was 100% in single/large mass assessment, similar to CT/MRI. For non HCC lesions such as regenerative and dysplastic nodules, the specificity was 50% vs 90% by CT/MRI. The positive role of CEUS in imaging spectrum of HCC included a provisional urgent diagnosis of an incidentally detected mass. It further led to a decrease in time for further management. A confident diagnosis on CEUS was possible in cases of characterization of an indeterminate mass, in situations where the patient was unfit for CT/MRI, was allergic to iodinated contrast or had claustrophobia, etc.CEUS was also cost effective, radiation free and an easy modality for monitoring post RFA or TACE lesions. CONCLUSION: CEUS is a valuable augmentation to the practice of ultrasonography, and an irreplaceable modality for confounding cases and interpretation of indeterminate lesions in imaging of HCC.  相似文献   

17.

Objectives

We investigated clinical utility of contrast-enhanced three-dimensional ultrasound (CE 3D US) imaging with contrast medium Sonazoid for demonstrating characteristic enhancement of hepatocellular carcinoma (HCC).

Methods

Among 115 focal liver tumors undergoing CE 3D US imaging, 70 HCCs confirmed with contrast-enhanced multi-detector computed tomography, contrast-enhanced magnetic resonance imaging or histopathologic examination were retrospectively analyzed. CE 3D US imaging was performed using Autosweep 3D scan functionality in the early, middle and late phase, after bolus injection of 0.2 ml Sonazoid. The CE 3D tomographic images reconstructed in parallel slices and sonographic angiogram images were independently reviewed by two reviewers. Kappa values were used to assess inter-reviewers’ agreement.

Results

TUI images showed most of HCCs were detected with intratumoral vessels and early tumor enhancement in the early phase, expressed homogenous or heterogeneous tumor enhancement in the middle phase, and became hypoechoic or isoechoic in the late phase. The kappa values in the early, middle and late phase for inter-reviewer agreements regarding the characteristic enhancement of tumors were 0.817, 0.774, and 0.785. In addition, TUI images demonstrated satellite foci and tortuous tumor vessels in three orthogonal planes. Sonographic angiogram reconstructed by different rendering modes showed the vessels and tumor stain in spatial view. The spatial configuration of anatomic structures was revealed on basis of both TUI and sonographic angiogram images.

Conclusion

CE 3D US imaging, with spatial visualization, is clinically useful to exhibit the characteristic enhancement of HCC tumors objectively.  相似文献   

18.

Purpose

To elucidate the changes in tumor vascularity and microbubble accumulation on contrast-enhanced sonograms, in relation to the dedifferentiation of hepatocellular carcinoma (HCC).

Materials and methods

This prospective study enrolled 10 patients with histologically proven HCC (14.4-39.0 mm, 26.1 ± 7.4) showing nodule-in-nodule appearance upon contrast-enhanced computed tomography. Contrast-enhanced ultrasound was performed by harmonic imaging under a low mechanical index (0.22-0.25) during the vascular phase (agent injection to 1 min) and late phase (15 min) following the injection of Sonazoid™ (0.0075 ml/kg). Contrast enhancement in the inner and outer nodules was assessed in comparison with that in adjacent liver parenchyma as hyper-, iso-, or hypo-enhanced.

Results

Vascular-phase enhancement of all 10 inner nodules was hyper-enhanced, and that of outer nodules was hyper-enhanced in 3, iso-enhanced in 2, and hypo-enhanced in 5. Late-phase enhancement of inner nodules was hypo-enhanced in 8 and iso-enhanced in 2. Furthermore, late-phase enhancement of outer nodules was iso-enhanced in the 7 lesions that showed iso- or hypo-enhancement in the vascular phase, and hypo-enhanced in the 3 with hyper-enhancement in the vascular phase. Late-phase hypo-enhancement was significantly more frequent in the nodules showing early-phase hyper-enhancement (11/13) than in the nodules showing early-phase iso- or hypo-enhancement (0/7) in both the inner and outer nodules.

Conclusion

Dedifferentiation of HCC may be accompanied by changes in tumor vascularity prior to a reduction in microbubble accumulation. Observation of the vascular phase may be more useful than late-phase imaging for the early recognition of HCC dedifferentiation when using contrast-enhanced ultrasound with Sonazoid.  相似文献   

19.

Objective

To compare the enhancement pattern of hilar cholangiocarcinoma on contrast-enhanced ultrasound (CEUS) with that on contrast-enhanced computed tomography (CECT).

Methods

Thirty-two consecutive patients with pathologically proven hilar cholangiocarcinomas were evaluated by both low mechanical index CEUS and CECT. The enhancement feature of the tumor, portal vein infiltration, and lesion conspicuity on them was investigated.

Results

In the arterial phase, the numbers of the lesions showing hyperenhancement, isoenhancement, and hypoenhancement, were 14 (43.8%), 14 (43.8%), and 4 (12.6%), on CEUS, and 12 (37.5%), 9 (28.1%), and 11 (34.4%), on CECT (P = 0.162). In portal phase, the numbers of the lesions showing hypoenhancement, isoenhancement, and hyperenhancement were 30 (93.8%), 1 (3.1%), and 1 (3.1%), on CEUS, and 23 (71.9%), 8 (25.0%), and 1 (3.1%), on CECT (P = 0.046). The detection rates for portal vein infiltration were 84.2% (16/19) for baseline ultrasound, 89.5% (17/19) for CEUS, and 78.9% (15/19) for CECT (all P > 0.05 between every two groups). CEUS significantly improved the lesion conspicuity in comparison with CECT. CEUS and CECT made correct diagnoses in 30 (93.8%) and 25 (78.1%) lesions prior to pathological examination (P = 0.125).

Conclusion

The enhancement pattern of hilar cholangiocarcinoma on CEUS was similar with that on CECT in arterial phase, whereas in portal phase hilar cholangiocarcinoma shows hypoenhancement more likely on CEUS. CEUS and CECT lead to similar results in evaluating portal vein infiltration and diagnosis of this entity.  相似文献   

20.
目的:探讨基于肝脏影像报告和数据管理系统(LI-RADS)的超声造影检查诊断肝细胞癌(HCC)的可行性。方法:回顾性分析108例有肝癌高风险的单发肝脏病变患者的超声造影资料,并基于LI-RADS分类标准对肝脏病变进行分析评估,并与病理或临床诊断结果相对照。结果:108个病灶中LI-RADS 1~5类病灶共106个:1类和2类病灶19个,临床客观诊断结果均为良性(阴性预测值为100%);3类病灶3个;22个4类病灶中17个为 HCC(阳性预测值为77.3%);62个5类病灶中有54个为 HCC(阳性预测值为87.1%)。受试者工作特征(ROC)曲线下面积为0.83(P<0.001)。若将LI-RADS 3~5类病灶归为阳性,基于LI-RADS的超声造影检查对HCC的诊断符合率为83.9%(92/106),敏感度为100%(73/73),特异度为57.6%(19/33),阳性预测值为83.9%(73/87),阴性预测值为100%(19/19);若将 LI-RADS 3类病灶排除、1~2类病灶归为阴性、4~5类病灶归为阳性,则诊断符合率为87.4%(90/103),敏感度为100%(71/71),特异度为59.4%(19/32),阳性预测值为84.5%(71/84),阴性预测值为100%(19/19)。结论:超声造影检查中应用LI-RADS分类标准诊断 HCC具有一定的可行性。  相似文献   

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