Contrast‐Enhanced Ultrasound Guidance for Interventional Procedures

Since its introduction, contrast‐enhanced ultrasound (CEUS) has gained an important role in the diagnosis and management of abdominal and pelvic diseases. Contrast‐enhanced ultrasound can improve lesion detection rates as well as success rates of interventional procedures when compared to conventional ultrasound alone. Additionally, CEUS enables the interventionalist to assess the dynamic enhancement of different tissues and lesions, without the adverse effects of contrast‐enhanced computed tomography, such as exposure to ionizing radiation and nephrotoxicity from iodinated contrast material. This review article describes the various applications and advantages of the use of CEUS to enhance performance of ultrasound‐guided interventions in the abdomen and pelvis.     

Contrast‐Enhanced Sonographically Guided Thermal Ablation for Treatment of Solid‐Organ Hemorrhage

The purpose of this series was to preliminarily evaluate the use of contrast‐enhanced sonographically guided percutaneous thermal ablation in the evaluation and treatment of solid‐organ bleeding by retrospectively analyzing 6 cases observed in clinical practice. Six patients who underwent contrast‐enhanced sonographically guided thermal ablation for treatment of solid‐organ bleeding (5 in liver and 1 in spleen) from December 2005 to August 2012 were included in this series. Clinical information, contrast‐enhanced sonograms before and after ablation, and the ablation method were retrospectively collected and analyzed. In 5 of the 6 patients, the location of the bleeding lesion was clearly seen. Hemostasis was successfully achieved in 4 of these 5 patients: 1 by radiofrequency ablation and 3 by microwave ablation. Ablation failed to achieve hemostasis in 1 patient who had postbiopsy splenic arterial bleeding because the bleeding vessel was a thick branch of the splenic artery. In the sixth remaining patient, who had bleeding after liver biopsy, hemostasis failed because contrast‐enhanced sonography did not precisely locate the bleeding lesion; hence, the ablation zone did not cover the whole lesion. Contrast‐enhanced sonographically guided ablation can be an alternative choice for treating solid‐organ bleeding because of its effectiveness and minimal invasiveness. However, it should be carefully investigated for those in whom the bleeding lesion cannot be located by contrast‐enhanced sonography and in those who have bleeding in a large vessel.     

Usefulness of contrast‐enhanced ultrasound in the diagnosis of biliary leakage following T‐tube removal

Biliary leakage is a serious complication related to T‐tube removal. Identifying the location of the leak is important for accurate diagnosis and prompt treatment. We report a case of biliary leakage in the common bile duct (CBD) following a T‐tube removal that was successfully diagnosed with contrast‐enhanced ultrasound (CEUS). The micro‐bubble contrast medium was administrated into the bile ducts through the percutaneous transhepatic biliary drainage catheter. The real‐time delineation of contrast agent leaking from the CBD was confirmed by percutaneous transhepatic cholangiography. CEUS can be used to detect biliary leakage after T‐tube removal. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2010     

Contrast‐Enhanced Transrectal Ultrasound for Follow‐up After Focal HIFU Ablation for Prostate Cancer

The optimal strategy for imaging after focal therapy for prostate cancer is evolving. This series is an initial report on the use of contrast‐enhanced transrectal ultrasound (TRUS) in follow‐up of patients after high‐intensity focused ultrasound (HIFU) hemiablation for prostate cancer. In 7 patients who underwent HIFU hemiablation, contrast‐enhanced TRUS findings were as follows: (1) contrast‐enhanced TRUS clearly showed the HIFU ablation defect as a sharply marginated nonenhancing zone in all patients; (2) contrast‐enhanced TRUS identified suspicious foci of recurrent enhancement within the ablation zone in 2 patients, facilitating image‐guided prostate biopsy, which showed prostate cancer; and (3) contrast‐enhanced TRUS findings correlated with multiparametric magnetic resonance imaging and biopsy histologic findings.     

超声造影引导经皮射频凝固治疗闭合性肝外伤的实验研究

目的研究超声造影（CEUS）引导经皮射频凝固（PRFA）治疗闭合性肝外伤（CHT）的价值。 方法建立8只猪CHT模型,采用CEUS引导射频针经皮穿刺进入肝损伤区进行凝固止血治疗,采用CEUS评估疗效,并剖腹探查验证。 结果CEUS共引导穿刺9次,其中,7只动物模型1次性引导穿刺PRFA凝固止血成功,另1只引导穿刺后第1次PRFA凝固止血不完全,再次CEUS引导穿刺并PRFA凝固止血成功。经剖腹探查证实。 结论CEUS在引导PRFA治疗CHT方面具有重要价值。     

Hepatocellular cancer response to radiofrequency tumor ablation: contrast-enhanced ultrasound

Radiofrequency ablation (RFA) is increasingly being used as percutaneous treatment of choice for patients with early stage hepatocellular carcinoma (HCC). An accurate assessment of the RFA therapeutic response is of crucial importance, considering that a complete tumor ablation significantly increases patient survival, whereas residual unablated tumor calls for additional treatment. Imaging modalities play a pivotal role in accomplishing this task, but ultrasound (US) is not considered a reliable modality for the evaluation of the real extent of necrosis, even when color/power Doppler techniques are used. Recently, newer microbubble-based US contrast agents used in combination with grey-scale US techniques, which are very sensitive to non-linear behavior of microbubbles, have been introduced. These features have opened new prospects in liver ultrasound and may have a great impact on daily practice, including cost-effective assessment of therapeutic response of percutaneous ablative therapies. Technical evolution of CEUS focusing on findings after RFA are illustrated. These latter are detailed, cross-referenced with the literature and discussed on the basis of our personal experience. Timing of CEUS posttreatment assessment among with advantages and limitations of CEUS are also described with a perspective on further technologic refinement.     

How to Develop a Contrast‐Enhanced Ultrasound Program

With the recent Food and Drug Administration approval of Lumason (sulfur hexafluoride lipid‐type A microsphere, Bracco Diagnostics Inc, Monroe Township, NJ) for contrast‐enhanced ultrasound (CEUS) to characterize focal liver lesions in both adult and pediatric patients, widespread use of CEUS is expected in the United States. This paper provides guidance in setting up a CEUS program, and reviews the practical details that will need to be instituted in a standard ultrasound department to provide both safe and efficient use of CEUS. A review of the indications, contraindications, adverse events, instructions for performing the exam, and image interpretation are discussed.     

Sonographically Guided High‐Intensity Focused Ultrasound for the Management of Uterine Fibroids

High‐intensity focused ultrasound therapy has received increasing interest in the management of solid malignancies and benign tumors. Magnetic resonance imaging has always been used to define the target for controlling and monitoring the ablation. Recently, sonographically guided high‐intensity focused ultrasound has been introduced to monitor the ablation process. This article provides an overview of the background, clinical use, and treatment outcomes of sonographically guided high‐intensity focused ultrasound in the treatment of uterine fibroids.     

Contrast‐enhanced sonography for screening of vascular complication in recipients following living donor liver transplantation

The purpose of this article is to discuss the role of CEUS for screening of vascular complication in recipients admitted to ICU following LDLT, effect of microbubble contrast agent on Doppler phenomenon, CEUS technique, and illustrate CEUS findings in recipients with complication following LDLT. CEUS can enhance the role of US in the diagnosis of postoperative vascular complication in recipients following living donor liver transplantation at the bedside. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound, 41:305–312, 2013     

Contrast-Enhanced Ultrasound in the Characterization of Hepatocellular Carcinomas Treated by Ablation: Comparison with Contrast-Enhanced Magnetic Resonance Imaging

The purpose of this study was to evaluate the clinical utility of low-mechanical-index contrast-enhanced ultrasound (CEUS) in assessing the response to percutaneous microwave ablation in patients with hepatocellular carcinoma by comparing the results with those of contrast-enhanced magnetic resonance imaging (CEMRI). Between August 2005 and July 2011, 182 patients with 231 lesions treated by microwave ablation were included in the study. One month after microwave ablation, CEUS and CEMRI were performed to evaluate therapeutic responses. The difference in diagnostic accuracy between the two methods was analyzed to evaluate the value of contrast-enhanced ultrasound after microwave ablation. The final diagnosis was based on computed tomography and MRI typical findings of therapeutic response of hepatocellular carcinoma, proven serum tumor marker levels and additional follow-up. The sensitivity of CEUS and CEMRI in evaluating the therapeutic effect of hepatocellular carcinoma was 86.5% and 84.6%; the specificity, 98.3% and 98.9%; and the accuracy, 95.7% and 95.7%.There was no significant statistical disparity between CEUS and CEMRI (p > 0.05).The sensitivity, specificity and accuracy were 98.1, 97.2 and 97.8% when CEUS was used in combination with CEMRI to evaluate the therapeutic response of hepatocellular carcinoma to microwave ablation. CEUS examination was proven to be a tolerable and easy modality for assessment of the therapeutic effect of microwave ablation and can provide results comparable to those obtained with CEMRI. Combining the results of these two examinations may reduce false-positive and false-negative diagnoses.     

超声造影在肝肿瘤热消融术中评估胆囊损伤的应用

目的探讨超声造影在胆囊旁肝肿瘤的热消融术中评估胆囊损伤的价值。 方法选取2016年1月至2017年3月在中山大学附属第三医院接受射频或微波消融治疗的患者40例,共42个胆囊旁肝肿瘤。采用常规超声检查评估患者术前术后胆囊壁厚度变化情况的同时,消融术中即时行超声造影检查评估胆囊壁血流灌注情况,判断胆囊壁损伤情况,并进行后续处理。通过随访评估胆囊旁肝肿瘤消融治疗的有效性、安全性。术前、术中及术后胆囊壁厚度的比较采用配对符号秩和检验。 结果与消融术前比较,40例接受消融治疗患者的胆囊壁术中评估有8例患者胆囊壁明显增厚。术中超声造影检查除2例评估为胆囊壁血流灌注缺损外,其他患者胆囊壁灌注较好,这2例患者行腹腔镜胆囊切除术并病理证实胆囊壁热损伤坏死（其中1例出现胆囊穿孔）,另有4例患者因多发胆囊结石行切除胆囊。34例保留胆囊患者中有6例在术后3 d内复查仍有胆囊壁增厚,后续随访中4例恢复,2例保持胆囊壁增厚状态,但均未出现胆囊消融热损伤相关症状。患者术中、术后的胆囊壁厚度与术前比较,差异均有统计学意义[5.00 mm（4.00~6.25 mm） vs 3.50 mm（3.00~5.00 mm）,Z=-3.741,P<0.001;5.0 mm（3.0~8.0 mm） vs 3.5 mm（3.0~5.0 mm）,Z=-3.735,P<0.001]。术后1个月增强CT/MRI检查证实41个病灶消融完全,完全消融率为97.6%（41/42）,所有消融完全病灶至随访结束均未发生局部肿瘤进展。 结论在超声引导下胆囊旁肝肿瘤消融术中即时行超声造影检查能够通过反映胆囊壁血流灌注状态判断胆囊壁消融热损伤情况。     

Intravenous and Intracavitary Use of Contrast‐Enhanced Ultrasound in the Evaluation and Management of Complicated Pediatric Pneumonia

Pediatric pneumonia can be complicated by necrotizing pneumonia or a parapneumonic effusion either in the form of an empyema or a clear effusion. Ultrasonography (US) and computed tomography represent well‐established modalities for evaluation of complicated pediatric pneumonia. Contrast‐enhanced ultrasound (CEUS) was recently introduced and is gaining increasing acceptance in pediatric imaging. In this case series, we present our initial experience with both intravenous and intracavitary use of CEUS in children with complicated pneumonia. Intravenous CEUS accurately and confidently showed necrotizing pneumonia and delineated pleural effusions, whereas intracavitary CEUS accurately identified the chest catheter location and patency and showed the presence of loculations, suggesting the use of fibrinolytics.     

Solitary necrotic nodule of the liver: contrast-enhanced sonography

PURPOSE: To report contrast-enhanced sonography (CEUS) for solitary necrotic nodule (SNN) of the liver and to assess its clinical value. METHODS: CEUS was performed in 17 patients with pathologically proven SNN. Contrast pulse sequencing and the contrast agent SonoVue were used to depict lesion vascularity at a low mechanical index. The enhancement patterns were evaluated in real time. RESULTS: Lesions were depicted as perfusion defects throughout all phases on CEUS. CONCLUSIONS: CEUS can be a convenient imaging modality for the differential diagnosis of SNN and may obviate the need for further imaging studies.     

Ultrasound‐guided thrombin injection in the treatment of iatrogenic arterial pseudoaneurysms: Single‐center experience

The aim of this study was to assess the safety and efficacy of ultrasound‐guided percutaneous thrombin injection for the treatment of postcatheterization arterial pseudoaneurysms. We evaluated retrospectively 82 consecutive subjects treated with percutaneous ultrasound‐guided thrombin injection of postcatheterization femoral (n = 79), brachial (n = 2), and radial (n = 1) pseudoaneurysms from January 2006 to April 2012. Pseudoaneurysm size, thrombin dose, and therapy outcome were documented. All pseudoaneurysm sacs were thrombosed with a single injection. The overall primary success rate (complete sac thrombosis) was 92.7%. A 30‐day Doppler ultrasound follow‐up showed a 100% procedural success. There were no complications. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42 :24–26, 2014     

肝癌射频消融术后超声造影引导下无水乙醇治疗肝癌的临床价值

目的：研究与常规超声引导相比较,超声造影(CEUS)引导下无水乙醇治疗射频消融术(RFA)后残存的肝癌有无优越性。方法：61例原发性肝癌的患者RFA术后行无水乙醇注射进行补充治疗,根据引导方式不同分为治疗组和对照组,治疗组运用超声造影引导方式,对照组采用常规超声引导方式,术后1个月对治疗病灶进行超声造影及增强CT的评价。结果：治疗组30个病灶,28个病灶达到完全灭活,2个病灶存有残存活性区达到部分灭活。对照组31个病灶,22个病灶达到完全灭活,9个病灶达到部分灭活。两者有统计学差异,(P＜0.05)。结论：运用超声造影引导可以有效的提高肝癌RFA术后无水乙醇治疗肝癌的疗效。     

Late‐onset type I endoleak characterized by contrast enhanced ultrasound after endovascular repair of aortic aneurysm

We report in the case of a patient with an intra‐abdominal aortic aneurysm treated with endovascular aneurysm repair (EVAR) who developed renal impairment during the period of follow up. The repair was complicated with an early‐onset type II endoleak which later evolved into a late‐onset type I endoleak. It was treated with proximal extension of stent graft, with treatment success and follow‐up documented on contrast enhanced ultrasound (CEUS). This case illustrates the usefulness of CEUS in post‐EVAR surveillance and emphasizes the need for life‐long monitoring as late‐onset complications are not uncommon.     

Qualitative diagnosis of hepatocellular carcinoma by contrast enhanced ultrasonography using Coded Harmonic Angio with Levovist

We attempted to evaluate diagnosis and characterization and to access therapeutic effects in cases of hepatocellular carcinoma (HCC) by contrast enhanced ultrasound (CEUS) using Coded Harmonic Angio (CHA) with Levovist, an intravenous ultrasound contrast agent. Fifty-seven HCC foci in 39 patients, including 37 HCC foci in 28 patients before and after transcatheter arterial chemoembolization or radio frequency ablation, were examined by CEUS using the CHA mode, which is under development. This mode uses digitally encoded pulse sequences that identify and suppress nonmoving tissue signals and enhance contrast signals from Levovist in a gray-scale format. In all cases, abundant tortuous intratumoral blood flow was visualized in the early vascular phase by continuous transmission, while tumor stain was recognized by consecutive 1-to-2 second intermittent transmission. Residual tumor area after treatment was also clearly depicted by intratumoral blood flow and partial enhancement. CEUS using CHA with Levovist is likely to become important in the qualitative diagnosis of hepatic tumor and to improve the efficacy of treatment for HCC.     

Endocavitary contrast‐enhanced ultrasound: A technique whose time has come?

Endocavitary use of contrast agents in sonography (US) is a relatively new method in diagnostic imaging, competing against gray‐scale US, fluoroscopy, and endoscopy. This article describes established indications, demonstrates the techniques of evolving applications, and discusses their potential benefits. These benefits include the ability to obtain precise information about the placement of drains and the extent of fluid collections, and to accurately identify the location and features of strictures in various organs, and those of complications of fluid collections or abscesses, without resorting to ionizing radiation. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound, 43 :71–80, 2015     

超声引导经皮微波消融甲状腺良性结节的应用研究

目的探讨超声引导下经皮穿刺微波消融治疗甲状腺良性结节的临床疗效及并发症等情况.方法选取本院诊治的甲状腺良性结节患者86例（156个结节）,术前细胞学检查确定为良性结节,行超声引导下经皮穿刺结节微波消融术后即刻超声造影,对不全消融结节行二次消融.在术后随访观察消融术后结节大小变化及并发症情况.同时与此期间在我院行甲状腺次全切除术的65例甲状腺良性结节患者作为对照组,分析两组患者的术后并发症出现人数及甲状腺功能恢复等.结果仅4/156枚需二次消融,一次消融率达97.4%.消融后第1、3、6及12个月体积缩小率分别为20.98%,45.37%,75.12%和86.83%;23/156（14.7%）枚结节在随访6-12个月内消失.观察组患者甲状腺功能恢复人数多于对照组,其术后并发症出现人数少于对照组（均P〈0.05）.结论微波消融治疗甲状腺良性结节疗效显著,并发症少,是传统手术治疗的一个有效补充.     

Behavior of Hepatocellular Adenoma on Real‐time Low‐Mechanical Index Contrast‐Enhanced Ultrasonography With a Second‐Generation Contrast Agent

Objective. The purpose of this study was to describe the behavior of histologically proven hepatocellular adenoma (HCA) on low‐mechanical index (MI) contrast‐enhanced ultrasonography (CEUS). Methods. A review of the databases from 4 academic hospitals revealed 18 patients (15 female and 3 male; mean age, 40 years; range, 25–71 years) with 25 histologically proven HCA lesions who were studied with CEUS at a low MI (0.04–0.1). Results. Twenty‐four of 25 lesions (96%; 95% confidence interval [CI], 80.5%–99.3%) showed high‐intensity enhancement, scored as 3 on a scale of 0 to 3, whereas only 1 lesion (4%; 95% CI, 0.7%–19.5%) was scored as 2. The time of peak enhancement ranged between 10 and 19 seconds (average, 13 seconds). All but 1 of the 25 lesions (96%; 95% CI, 80.5%–99.3%) showed early homogeneous and centripetal enhancement during the hepatic arterial phase. No portal venous phase enhancement was observed in any lesion because all showed rapid wash‐out (100%; 95% CI, 86.7%–100%). Twenty lesions (80%; 95% CI, 60.9%–91.1%) were found to be isoechoic to slightly hypoechoic during the portal phase, and 19 (76%; 95% CI, 56.6%–88.5%) were isoechoic to mildly hypoechoic, whereas 7 (24%; 95% CI, 11.5%–43.4%) were hypoechoic during the late phase. Conclusions. Contrast‐enhanced ultrasonography is an effective technique for identifying the microvascular and macrovascular characteristics of HCA. Typically, HCA shows early (10–19 seconds) and centripetal enhancement during the arterial phase and isoechogenicity or mild hypoechogenicity during the portal phase, remaining slightly hypoechoic or isoechoic during the late phase in most cases.