Renal infarct: contrast-enhanced power Doppler sonographic findings

Power Doppler sonography (PDUS) is a promising technique for the diagnosis of renal infarcts. PDUS's efficacy may be enhanced by using sonographic contrast agents. We evaluated 3 cases of renal infarction using PDUS and the sonographic contrast agent Levovist. The findings were compared with those of other imaging modalities, such as scintigraphy, CT, and angiography. In case 1, PDUS showed a patent interlobar artery only in the lower part of the right kidney and no other perfusion of the right renal parenchyma. Contrast-enhanced PDUS showed patchy areas of preserved perfusion in the lower and middle-upper anterior portions of the kidney. In case 2, PDUS showed diffuse and patchy perfusion defects in the anterolateral portion of the right kidney. On contrast-enhanced PDUS, no signal enhancement was seen in these areas, but the perfusion defects were better delineated. In case 3, PDUS showed no perfusion in the upper pole of the kidney; the nonperfused area extended to the posterior upper portion of the kidney but could not be distinguished from normal tissue. After injection of the contrast agent, there was no enhancement of the posterior extension of the upper pole infarct, but Doppler signals from the surrounding normal parenchyma were enhanced, so the area was more clearly demarcated. The administration of the contrast agent facilitated the visualization of the infarcts in all 3 cases.     

Diagnostic efficacy of contrast-enhanced ultrasonography in solid renal parenchymal lesions with maximum diameters of 5 cm.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic efficacy of contrast-enhanced ultrasonography (CEUS) using a sulfur hexafluoride contrast agent and the cadence contrast pulse sequencing mode in differentiating solid renal parenchymal lesions (SRPLs) with a maximum diameter of 5 cm. METHODS: Seventy-one patients with 72 SRPLs with a maximum diameter of 5 cm underwent conventional ultrasonographic and CEUS examinations in our department. The final diagnoses were 44 renal cell carcinomas (RCCs; confirmed by pathologic examination), 24 renal angiomyolipomas (4 by pathologic examination and 20 by computed tomography, magnetic resonance imaging, and follow-up studies), 1 oncocytoma (by pathologic examination), 2 hypertrophied columns of Bertin, and 1 renal abscess (both by computed tomography, magnetic resonance imaging, and follow-up studies). Three observers who were blinded to other results and the final diagnoses reviewed the conventional ultrasonographic and CEUS images. RESULTS: Hyperenhancement in the late phase (30-90 seconds after agent injection) was the most important finding for predicting SRPLs with a maximum diameter of 5 cm to be RCCs. With this criterion, the specificity and sensitivity for diagnosing solid RCCs (相似文献   

Pancreatic carcinoma versus chronic focal pancreatitis: contrast-enhanced power Doppler ultrasonography findings

Background We assessed the potential usefulness of contrast-enhanced power Doppler ultrasonography (US) for differentiating pancreatic carcinoma from chronic focal pancreatitis.Methods Twenty-six consecutive patients with ductal carcinoma (n=16) and chronic focal pancreatitis (n=10) underwent power Doppler US examinations before and after intravenous injection of an air-based contrast agent (Levovist, Schering, Berlin, Germany). Final diagnosis was obtained by surgery in all patients. The following parameters before and after intravenous administration of contrast agent were evaluated for each lesion: number, morphology and course of the vessels within the lesion and time to maximum detectable enhancement. Number of the lesion vessels and time to maximum enhancement for each lesion were compared by with Student t test. Results After injection of contrast agent, nine of 16 (56.2%) carcinomas showed a larger total number of vessels (p < 0.005) and faster enhancement (p < 0.0001) compared with chronic focal pancreatitis. Irregular vessels with a serpiginous course that penetrated the tumor was predominant in carcinoma (eight of 16 cases), whereas focal pancreatitis presented mostly as avascular masses (five of 10 cases).Conclusion Contrast-enhanced power Doppler US provides useful findings for differentiating pancreatic carcinoma from chronic focal pancreatitis.     

Evaluation of joint effusion in rabbits by color Doppler, power Doppler, and contrast-enhanced power Doppler ultrasonography

PURPOSE: The aim of this prospective study was to evaluate the diagnostic value of power Doppler ultrasonography (PDUS) and contrast-enhanced PDUS (CEPDUS) in the depiction and characterization of experimentally induced arthritis in the rabbit. MATERIALS AND METHODS: Thirty rabbits were divided into three groups consisting of one control group (saline injection group) and two experimental groups: a suppurative arthritis group and a chemically induced synovitis group. The same amount (1 ml) of each agent was directly injected into the right hip joint. Serial color Doppler ultrasound (CDUS), PDUS, and CEPDUS images were obtained before and after injection. RESULTS: We observed that all of the infected knees in the suppurative arthritis group with Staphylococcus aureus demonstrated an increased signal on PDUS after inoculation. A minimal power Doppler signal was presented in the chemically induced synovitis group with talc injection, but none of the control knees demonstrated any increased signals. CEPDUS was the most sensitive imaging modality for evaluating the increase of blood flows in suppurative arthritis and was subsequently followed by PDUS and CDUS. CONCLUSION: The increased signals obtained with PDUS represent increased local blood flows; therefore, this technique can be used for evaluating the degree of inflammation. Furthermore, using the contrast agent enhances the sensitivity of PDUS, and it can even be useful for differentiating borderline cases.     

对比超声造影与CT诊断肾细胞癌

目的 探讨CEUS与CT诊断肾细胞癌(RCC)的价值。方法 对可疑肾脏占位性病变患者92例行CEUS和CT增强扫描检查,并与术后病理结果比较,计算CEUS及CT增强扫描诊断RCC的敏感度、特异度及准确率。结果 CEUS和CT增强扫描在RCC增强程度、增强减退情况及假包膜征方面差异有统计学意义(P<0.05)。CEUS及CT增强扫描诊断RCC的敏感度、特异度和准确率分别为95.89%(70/73)、57.14%(8/14)、89.66%(78/87)和78.08%(57/73)、50.00%(7/14)、73.56%(64/87)。结论 CEUS显示RCC低速血流、微循环血供及诊断敏感度和准确率均优于CT增强扫描。     

肾细胞癌超声造影与血管生成的相关性研究

目的探讨肾细胞癌超声造影峰值强度与血管生成的相关性。方法采用对比脉冲序列技术及ACQ定量分析软件,对25例肾细胞癌患者共25个病灶进行超声造影检查并记录超声造影的峰值强度;免疫组织化学方法分析肾细胞癌组织中微血管密度(MVD),比较超声造影峰值强度与MVD之间的相关性。结果肾细胞癌超声造影峰值强度平均为(139.21±17.22)dB;MVD值平均为36.39±10.56,肾细胞癌超声造影峰值强度与MVD之间存在着显著的相关性(r=0.819,P<0.05)。结论肾细胞癌超声造影峰值强度与肿瘤内的血管生成存在显著的相关性,可用于术前评价肾细胞癌的血管生成状况。     

超声造影在肾细胞癌亚型鉴别诊断中的价值

目的探讨超声造影在肾细胞癌亚型鉴别诊断中的应用价值。方法 2004年6月至2010年2月常规超声和超声造影检查343例肾细胞癌患者346个病灶,均经手术及病理证实。常规超声观察肿瘤的大小、回声、边界、有无彩色血流信号、血管位置等。超声造影观察病灶的增强方式和增强时相,包括起始时间、达峰时间、消退时间及病灶的增强表现。结果经手术和病理证实304个病灶为透明细胞肾癌,23个为乳头状肾癌,19个为嫌色细胞肾癌。不同亚型肾细胞癌常规超声表现没有明显差异。不同亚型肾细胞癌的增强时相差异无统计学意义(P>0.05)。透明细胞肾癌表现为皮质期同步增强、达峰值时呈高回声和等回声、实质期快速减退为主,而乳头状肾癌和嫌色细胞肾癌皮质期表现为同步增强和缓慢增强、达峰值时呈低回声和等回声、实质期以快速减退为主。乳头状肾癌与透明细胞肾癌比较,两组病灶皮质期、达峰值回声和实质期的表现差异有统计学意义(P均=0.000);嫌色细胞肾癌与透明细胞肾癌比较,两组病灶皮质期、达峰值回声和实质期的表现差异有统计学意义(P=0.000,P=0.000,P=0.001)。结论超声造影有助于肾细胞癌亚型的鉴别。     

Three-dimensional power Doppler ultrasonography during pregnancy.

OBJECTIVES: To present the appearance of fetal and placental vascular anatomic structures by three-dimensional power Doppler ultrasonography. METHODS: Three-dimensional multiplanar imaging, surface rendering, and volume rendering were combined with power Doppler ultrasonography to show the methods, imaging artifacts, and diagnostic potential of this technology during pregnancy. RESULTS: Fetuses with normal and abnormal vascular anatomic structures were evaluated by three-dimensional power Doppler ultrasonography. The combination of several imaging modalities (e.g., three-dimensional multiplanar imaging, surface rendering, and volume rendering) with power Doppler ultrasonography is shown. CONCLUSIONS: Three-dimensional power Doppler ultrasonography is an important adjunctive method that can be used to characterize normal vascular development and circulatory anomalies of the fetus.     

Detection of tumor vascularity in hepatocellular carcinoma with contrast-enhanced Dynamic Flow imaging: Comparison with contrast-enhanced power Doppler imaging

Objective: To compare the effectiveness of contrast-enhanced Dynamic Flow imaging and contrast-enhanced power Doppler imaging using Levovist^? as a microbubble contrast agent in evaluating intratumoral vascularity in hepatocellular carcinoma (HCC).Materials and Methods: Twenty-nine patients with 54 hepatocellular carcinoma nodules (before treatment, 31; after treatment, 23) were studied with both Dynamic Flow and power Doppler imaging with intravenous injection of Levovist^?. Tumor vascularity was categorized as 0, no blood flow signals within the tumor; 1, dotlike blood flow signals within the tumor; 2, moderate blood flow signals within the tumor; and 3, abundant blood flow signals within the tumor. Detectability of intratumoral vascularity of hepatocellular carcinoma in three groups based on tumor depth, blooming and noise artifacts on contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging were also compared with results obtained using dynamic CT as a the gold standard. The effectiveness of contrast-enhanced Dynamic Flow and contrast-enhanced power Doppler imaging in assessing therapeutic effect were compared at the same time.Results: The ability of contrast-enhanced Dynamic Flow Doppler imaging to detect tumor vascularity in the superficial and intermediate hepatocellular carcinoma groups was close to that of contrast-enhanced power Doppler imaging (p>0.05). However, contrast-enhanced Dynamic Flow imaging demonstrated tumor parenchymal stain in 28 hepatocellular carcinoma nodules (61%), which was not detected by contrast-enhanced power Doppler imaging. Further, significantly fewer artifacts appeared in contrast-enhanced Dynamic Flow imaging than in contrast-enhanced power Doppler imaging (p<0.001). In assessing therapeutic response, the sensitivity of contrast-enhanced Dynamic Flow imaging was similar to that of dynamic CT. In deep areas, however, those more than 6 cm below the surface of the body, contrast-enhanced Dynamic Flow imaging was less sensitivity than contrast-enhanced power Doppler imaging (p=0.005).Conclusion: Contrast-enhanced Dynamic Flow imaging provides an effective approach to assessing intratumoral vascularity and therapeutic response in HCC lesions situated less than 6 cm from the surface of the body. It is superior to contrast-enhanced power Doppler imaging in its ability to detect tumor parenchymal stain and production of fewer artifacts.     

Usefulness of intraoperative contrast-enhanced ultrasonography in laparoscopic enucleation of small pancreatic metastases from renal cell carcinoma: A case report

Pancreatic metastasis from renal cell carcinoma (RCC) is relatively rare. Surgical resection of the lesion is recommended if no residual tumor remains. Although there is no clear standard for surgical procedures, enucleation can be considered for small lesions. Lesion identification is important for enucleation, and contrast-enhanced ultrasound which takes advantage of the characteristics of hypervascular lesions was useful in a 68-year-old woman who underwent a left nephrectomy for RCC 11 years ago that was pathologically diagnosed as clear cell carcinoma. Recent computed tomography checkup showed a hypervascular tumor of 6 mm in the uncinated process and 10 mm in the pancreatic tail. Endoscopic ultrasonography-guided fine-needle aspiration was performed for the tail lesion, a diagnosis of clear cell carcinoma was made, and laparoscopic enucleation of the pancreatic tumors was performed aided by intraoperative contrast-enhanced ultrasound. The postoperative course was uneventful, and no pancreatic fistula occurred.     

定性及定量评价不同大小肾透明细胞癌超声造影特征

目的 定性及定量评价不同大小肾透明细胞癌超声造影特征。方法 回顾性分析106例肾透明细胞癌患者超声造影图像。按最大径将病灶分成三组（≤4cm、4～7cm及＞7cm）。定性分析癌灶造影剂到达时间、增强程度、灌注是否均匀及环状高增强征象;定量分析癌灶及肾皮质峰值强 度、上升时间、达峰时间、灌注速率、平均渡越时间及曲线下面积,比较组间各参数差异及癌灶与肾皮质间定量参数差异。结果 达到时间、灌注是否均匀及环状高增强征象组间差异有统计学意义（均P＜0.05）;癌灶内峰值强度及曲线下面积组间差异有统计学意义（均P＜0.05）,癌灶与肾皮质定量参数差异在≤4cm组中均无统计学意义,在4～7cm及＞7cm组中,癌灶峰值强度及曲线下面积大于肾皮质,差异有统计学意义（均P＜0.05）。结论 不同大小肾透明细胞癌超声造影特征不同,定性和定量评价能对其超声诊断提供更多信息。     

Flash-echo gray-scale imaging in the subtraction mode for assessing perfusion of small hepatocellular carcinoma

PURPOSE: The aim of this study was to evaluate the effectiveness of using flash-echo imaging (FEI) in the subtraction mode to assess the vascularity of small hepatocellular carcinomas (HCCs) that had been unsatisfactorily assessed with power Doppler sonography. METHODS: Between May 2000 and April 2001, we prospectively assessed nodular small HCCs using FEI in the subtraction mode after power Doppler sonography resulted in unsatisfactory images. After microbubble contrast was injected, we used the FEI technique to assess tumor perfusion in the arterial, portal, and delayed phases. RESULTS: Our study population comprised 14 patients (10 men and 4 women) whose ages ranged from 31 to 79 years (mean, 61 +/- 13.7 years) and whose tumors ranged in size from 0.8 to 3 cm (mean, 1.8 +/- 0.5 cm). Power Doppler sonography was unable to assess tumor vascularity in 6 cases because of interference by heart pulsation, and it failed to detect a color signal in the other 8 cases. All tumors were enhanced with FEI. In the arterial phase, 7 of the 14 tumors (50%) showed hyperperfusion relative to liver parenchyma enhancement, 5 of 14 (36%) showed isoperfusion, and 2 of 14 (14%) showed hypoperfusion. In the portal phase, 3 of the 14 tumors (21%) showed isoperfusion, and the other 11 (79%) showed hypoperfusion. In the delayed phase, all 14 tumors showed hypoperfusion. CONCLUSIONS: Despite heart pulsation and slow vascular flow, FEI in the subtraction mode was sensitive and effective in assessing the perfusion of small HCCs.     

Contrast-enhanced ultrasonography in the diagnosis of solid renal tumors.

OBJECTIVE: The purpose of this study was to evaluate the usefulness of contrast-enhanced ultrasonography (CEUS) in the diagnosis of solid renal tumors. METHODS: Twenty-nine patients with solid tumors detected on gray scale ultrasonography underwent resection for suspected renal malignancy. Findings of arterial phase contrast computed tomography (CT) and CEUS were compared for each diagnosis. RESULTS: Histopathologic examination of resected lesions showed malignancy in 26 patients (clear cell carcinoma, n = 18; papillary renal cell carcinoma, n = 6; collecting duct carcinoma, n = 1; and infiltrative urothelial carcinoma, n = 1) and benign tumors in 3 patients (oncocytoma, n = 2; and angiomyolipoma, n = 1). Contrast CT failed to show tumor blood flow in 5 of 29 patients, whereas CEUS showed this in all patients. Positive predictive values of CEUS and contrast CT in the diagnosis of renal malignancy were 100% and 82.8%, respectively. Among clear cell carcinomas, hypervascularity was observed on contrast CT in 16 of 18 patients and on CEUS in 17 of 18 patients. On the basis of hypervascularity, diagnostic sensitivity values for clear cell carcinoma were 94.4% for CEUS and 88.9% for contrast CT, whereas specificity values were 45.5% for CEUS and 72.7% for contrast CT. Among papillary cell carcinomas, contrast CT showed avascular lesions in 4 of 6 patients. However, CEUS showed blood flow in these lesions, leading to diagnosis of hypovascular renal tumors. CONCLUSIONS: Contrast-enhanced ultrasonography was more sensitive for detecting slight tumor blood flow than contrast CT and was useful in preoperatively diagnosing malignant hypovascular renal tumors but was less so for hypervascular renal tumors.     

Value of contrast-enhanced power Doppler sonography using a microbubble echo-enhancing agent in evaluation of small breast lesions

PURPOSE: The purpose of this study was to prospectively evaluate the usefulness of contrast-enhanced power Doppler sonography (PDUS) using a microbubble echo-enhancing agent in differentiating between malignant and benign small breast lesions. PATIENTS AND METHODS: Between July 1, 2000, and September 30, 2001, we performed gray-scale sonographic examination of patients in whom diagnostic sonography or screening mammography had revealed solid breast lesions measuring less than 2 cm in the largest dimension. The patients were then examined on PDUS before and after injection of a microbubble contrast agent. The sonographic findings for all 3 techniques, as well as the morphologic features of the Doppler signals for each patient before and after injection of the contrast agent on PDUS, were independently assessed. Each lesion was classified as "benign" or "malignant" on the basis of specific criteria for sonographic interpretation. A hemodynamic study was performed in which time-transit profiles of the Doppler signals on contrast-enhanced PDUS were generated using a computer-assisted program, and the results for each patient were compared with the findings of a histopathologic examination of surgical specimens. RESULTS: Thirty-six patients (35 women and 1 man) with a mean age of 43.5 years (range, 18-69 years) were evaluated. The tumors ranged from 4 to 19 mm in the largest dimension. Histopathologic examination revealed that 19 tumors were benign and 17 were malignant. For morphologic diagnosis of the malignant lesions, the sensitivity of gray-scale sonography was 100%, compared with 29% for PDUS without contrast enhancement. The specificity of gray-scale sonography was 47%, compared with 74% for PDUS without contrast enhancement. Contrast-enhanced PDUS had a sensitivity of 71% and a specificity of 58%. The diagnostic accuracy was 72% for gray-scale sonography, 53% for PDUS without contrast enhancement, and 64% for contrast-enhanced PDUS. The time-transit profiles of the hemodynamic study did not reveal a statistically significant difference in the accuracy rates of contrast-enhanced PDUS between benign and malignant breast lesions. CONCLUSIONS: Compared with PDUS without contrast enhancement, contrast-enhanced PDUS provides better visualization of the morphology of vascular Doppler signals that is characteristic of malignancy and therefore has a higher sensitivity and diagnostic accuracy, albeit a lower specificity. In differentiating between benign and malignant small breast lesions, contrast-enhanced PDUS can be helpful when used with gray-scale sonography and PDUS without contrast enhancement.     

Solitary metastasis from renal cell carcinoma presenting as diffuse pancreatic enlargement

Late metastasis of renal cell carcinoma (RCC) to the pancreas is uncommon. Diffuse pancreatic metastasis of any carcinoma rarely causes global enlargement of the pancreas. We present the case of a 73-year-old man diagnosed with metastatic RCC of the pancreas 9 years after radical nephrectomy had been performed and describe our radiologic findings. The disease involved the entire pancreas, which was hypoechoic on sonography, hypodense on CT without contrast enhancement, and markedly hyperdense after intravenous administration of a contrast agent. Color Doppler sonography showed that the involved areas of the pancreas had increased color flow signals, indicating that the metastatic tumor was characteristically hypervascular. In patients with a history of RCC, color or power Doppler sonographic demonstration of diffuse enlargement of the pancreas with evidence of hypervascularity may indicate metastasis of RCC to the pancreas.     

肾血管平滑肌脂肪瘤破裂出血彩色多普勒超声及超声造影表现

目的 总结肾血管平滑肌脂肪瘤破裂出血的彩色多普勒超声及超声造影表现。方法 回顾性分析我院2005年1月至2010年1月7例经手术病理证实的肾血管平滑肌脂肪瘤破裂出血患者的彩色多普勒超声及超声造影声像图表现。结果 7例患者均行彩色多普勒超声检查,声像图表现为肾区肿物呈不规则形、边界不清、不均匀混合回声,以高回声为主,后方回声均见明显衰减。瘤体内可见丰富的迂曲走行的动静脉血流信号。肾包膜下血肿表现为边界清晰的低回声区或界限不清的混合性回声区。其中2例行超声造影检查,表现为：各期均呈高增强,增强形态为周边呈结节状高增强,逐渐向中心填充,增强欠均匀。肾包膜下血肿造影各期均表现为新月形无增强区,造影后血肿与瘤体分界清晰。结论 肾血管平滑肌脂肪瘤破裂出血无论在彩色多普勒超声表现,还是在超声造影表现上,其瘤体仍保留着原发病变即肾血管平滑肌脂肪瘤的特征。肾包膜下血肿在超声造影表现为各期无增强,与瘤体分界截然,有利于明确其范围。常规超声结合超声造影有利于肾血管平滑肌脂肪瘤破裂出血的诊断。     

超声造影应用Bosniak分级诊断肾囊性病灶的价值

目的 探讨CEUS应用Bosniak分级诊断肾囊性病灶的价值,并与增强CT比较。方法 收集同期接受CEUS和增强CT检查的52例患者共68个肾囊性病灶,观察病灶的形态、边壁、分隔、实性结节及血流灌注情况,评价2种方法分级诊断肾囊性病灶的价值。结果 良性组中,25个病灶(25/31,80.65%)CEUS和增强CT均表现为单房或多房囊性病灶,内无分隔或伴纤细分隔,分隔无强化或轻度强化,仅3个病灶(3/31,9.68%)表现为多房囊性病灶伴多个实性结节,2个病灶(2/31,6.45%)表现为花瓣样增强,分隔不规则增厚,1个病灶(1/31,3.23%)表现为网状增强;恶性组中,32个病灶(32/37,86.49%)CEUS和增强CT均表现为多房囊性病灶伴多个实性结节或不规则实性增强区,4个病灶(4/37,10.81%)表现为分隔较厚的多房性囊性病灶,1个病灶(1/37,2.70%)表现为边壁不规则增厚的单房囊性病灶;以Ⅳ级为诊断标准,CEUS和增强CT诊断囊性肾癌的敏感度、特异度、准确率分别为67.57%和70.27%,93.55%和96.77%,79.41%和82.35%。以Ⅲ级及以上为诊断标准,CEUS和增强CT诊断囊性肾癌的敏感度、特异度、准确率分别为97.30%和100%,74.19%和 80.65%,86.76% 和91.18%。分隔数目≥3条及分隔厚度≥1.75 mm可作为诊断肾囊性病灶良恶性的最佳诊断界值。结论 CEUS结合Bosniak标准鉴别诊断肾囊性病灶的良恶性具有较高的价值。     

超声造影鉴别诊断肾透明细胞癌和肾血管平滑肌脂肪瘤

目的 比较肾透明细胞癌(CCRCC)和肾血管平滑肌脂肪瘤(AML)的超声造影声像图表现,探讨超声造影对二者的鉴别诊断价值.方法 回顾106个CCRCC和25个AML的超声造影声像图表现,观察指标包括肿瘤的增强程度、增强均匀度、包膜增强、增强消退情况以及增强方式,分析超声造影声像图特征对肾癌的鉴别诊断价值.结果 肿瘤的增强程度和增强消退时间在CCRCC与AML之间差异无统计学意义(P>0.05),而增强均匀度、包膜增强以及增强方式差异有统计学意义(P<0.01).表现为不均匀增强、包膜增强以及弥漫性增强的肿瘤具有恶性倾向,其阳性预测值分别为97.26%、100%、94.74%.如将肿瘤同时具有这3种声像图特征作为CCRCC的诊断标准,其阳性预测值和阴性预测值达100%及95.00%.结论 CCRCC和AML具有不同的超声造影声像图特征,超声造影有助于二者的鉴别诊断.