Hepatocellular nodules in liver cirrhosis: contrast-enhanced ultrasound

Contrast-enhanced ultrasound (CEUS) using microbubble contrast agents has expanded the role of US in the diagnosis of liver nodules in high risk patients for hepatocellular carcinoma (HCC). HCC is typically characterized by arterial hypervascularity and later washout (negative enhancement). Washout in the portal phase is often not obvious until late (>90 s). Benign nodules such as regenerative nodules or dysplastic nodules are usually isoechoic or slightly hypoechoic in the arterial and portal venous phases. However, there are occasional cases with overlap of imaging features between benign and malignant nodules, including hypovascular HCC and hypervascular HCC without washout. CEUS is helpful to characterize potential mimickers of HCC on imaging such as nontumorous arterioportal shunt or hemangioma. CEUS is also useful for a guidance of percutaneous local therapy of HCC and post-procedure monitoring of therapeutic response. CEUS can be effectively used in the diagnostic algorithm of small (1–2 cm) newly detected nodules during HCC surveillance.     

Visualization of blood flow in hepatic vessels and hepatocellular carcinoma using B-flow sonography

PURPOSE: A B-flow sonographic technique was recently developed to provide direct visualization of blood flow with gray-scale sonography. Compared with color Doppler sonography, B-flow imaging has wideband resolution and a high frame rate. The purpose of this study was to evaluate the usefulness of B-flow sonography for visualizing blood flow in hepatic vessels and tumor vascularity in patients with liver cirrhosis or hepatocellular carcinoma (HCC). METHODS: Twenty-five patients with liver cirrhosis, including 15 with HCC, were studied by B-flow and color Doppler sonography. Blood-flow detection rates in portal veins and hepatic arteries and tumor vascularity in HCC were analyzed, and the 2 methods were compared. RESULTS: Using B-flow, blood flow was visualized in the portal vein in 23 (92%) of 25 patients and was visualized in the hepatic artery separately from the portal vein in 9 (36%) of 25 patients. The blood-flow signals were visualized only within vessels, never "bleeding" outside the vessel's lumen. Blood flow in the portal vein was observed with color Doppler sonography in all 25 patients, but the hepatic artery was never clearly separated from the portal vein. Vascularity within the HCC tumor was detected in 9 (60%) of 15 nodules with B-flow imaging, and fine arteries flowing into the tumor were observed in 6 nodules. Color Doppler sonography detected blood flow in 13 (87%) of the 15 HCC nodules. CONCLUSIONS: Blood flow in hepatic vessels and tumor vessels of HCC were visualized with B-flow sonography. B-flow sonography is a potentially useful technique for the evaluation of liver vascularity and intratumoral vessels.     

Magnetic resonance of focal liver lesions in hepatic cirrhosis and chronic hepatitis.

Detection of focal liver nodules in patients with cirrhosis continues to be a radiologic challenge despite progressive advances in liver imaging in the past 2 decades. Patients with hepatic cirrhosis have a high predisposition to develop hepatocellular carcinoma (HCC), and the early detection and diagnosis of this tumor is very important because the most effective treatment is surgical resection, transplantation, or local ablation therapy when the tumor is small. Cirrhotic livers are mainly composed of fibrosis, together with a broad spectrum of focal nodular lesions ranging from regenerative nodules to premalignant dysplastic nodules to overt HCC. Awareness of such lesions and interpretation of imaging studies in these patients requires a critical review to detect subtle tumors, and a thorough understanding of the imaging appearance of the malignant and benign masses that can occur in the cirrhotic liver. Although the recent advances in liver imaging techniques, especially computed tomography (CT) and magnetic resonance (MR), have facilitated the detection and characterization of focal liver nodules in cirrhotic patients, discriminating between HCC and precancerous nodules remains problematic with all available imaging techniques. Nevertheless, MR imaging appears to have more potential than other imaging techniques in the study of cirrhotic patients and MR may be more appropriate than the other imaging modalities for the detection of small HCCs. In this article we review the imaging characteristics of nodular focal lesions that arise in cirrhotic livers, with special attention to MR imaging features.     

Small hepatic nodules in cirrhosis: ultrasonographic, CT, and MR imaging findings

Purpose: The purpose of this study was to assess the imaging findings of pathologically-proved small hepatic nodules 2 cm in size or smaller detected with ultrasonography in cirrhotic patients with suspected hepatocellular carcinoma (HCC). Materials and Methods: We evaluated sonographically detected 32 small hepatic nodules which were pathologically confirmed in 23 consecutive cirrhotic patients who were suspected of having HCC. Twenty-six lesions were confirmed with ultrasonographically-guided aspiration needle-core biopsy, and six with definitive surgery. Ultrasonographic examination records were retrospectively reviewed. CT, and MR images obtained with various imaging techniques were retrospectively reviewed by two radiologists in a blind fashion. Results: The 32 hepatic nodules were comprised of seven focal fatty changes, two large regenerative nodules, three low-grade dysplastic nodules, five high-grade dysplastic nodules, and fifteen HCCs. Ultrasonography showed various echogenicity for the hepatic nodules. The signal-intensity characteristics with T1-weighted spin-echo, in-phase gradient-recalled-echo, and dynamic MR imagings may be useful in distinguishing HCC from nonHCC nodules. Conclusions: Nearly half of small hepatic nodules detected with ultrasonography were nonHCC nodules. Ultrasonographic findings may not be reliable in characterizing small hepatic nodules in cirrhosis. CT and MR imaging obtained with the various techniques are still insensitive to these hepatic nodules. RID="ID="<e5>Correspondence to:</e5> M. Kanematsu Received: 25 August 1997/Revision accepted: 19 November 1997     

The role of CEUS in the characterization of hepatocellular nodules detected during the US surveillance program--current practices in Europe

The basic pathological feature for the differential diagnosis between hepatocellular carcinoma (HCC) and non-malignant hepatocellular nodules in cirrhotic patients detected during ultrasound (US) is the vascular supply to the nodule. Computed tomography (CT) and magnetic resonance imaging (MRI) are considered reference imaging techniques for depicting hepatocellular nodule vascularity in the noninvasive diagnosis of HCC. Contrast-enhanced US (CEUS) improves the diagnostic performance of unenhanced US in the diagnosis of HCC, giving an overall diagnostic accuracy that is similar to that of CT, even for nodules smaller than 2 cm. An additional diagnostic feature of CEUS relative to CT is the possibility to visualize contrast wash-in to hepatic nodules during the arterial phase and contrast washout during the portal venous and late phases. Sensitivity for the diagnosis of HCC with combined assessment of CEUS and CT is higher than for separate assessments of CEUS and CT due to the reduction of false-negative findings. CEUS represents a competitive imaging method from an economic point of view, and is an effective imaging tool for assessing the therapeutic outcome after surgery, ablation therapy, and transarterial chemoembolization (TACE).     

Harmonic imaging in fetal echocardiography.

Noncontrast harmonic imaging (HI) has been shown to improve image quality in adults with poor acoustic windows. The utility of fetal echocardiography may be limited by suboptimal acoustic windows, and the use of HI in fetal echocardiography has not previously been defined. The purpose of this study was to compare the quality of fundamental imaging (FI) and HI in fetal echocardiography. Sixty-two fetal echocardiograms, including 44 (71%) with limited acoustic windows, were performed with the use of FI and HI. Image quality and visualization of the ventricles, valves, and the aortic and ductal arches were evaluated and compared between FI and HI. Mean HI scores were higher than mean FI scores for all the structures evaluated. Compared with FI, HI improved the image quality and visualization of cardiac structures in this group of fetuses with predominantly suboptimal acoustic windows. Harmonic imaging is a useful adjunct to FI in echocardiography, and the benefits of HI extend to cardiac imaging in the fetus.     

编码谐波造影在小肝癌瘤内血流检测中的应用

目的：探讨编码谐波声学造影在检出小肝癌内血流信号中的应用价值。方法：对106个最大直径不超过3cm的肝癌结节行编码谐波声学造影检查，造影剂为levovist，分别在早期动脉相和门脉相评价肝癌瘤内的血流信号，所得结果与三相动态CT，数字减影血管造影和MRI对比。结果：106个肝癌结节中98个可在早期动态相和／或门脉相检出瘤内血流信号，以三相动态CT结果为金标准，其检出的敏感性，特异性和准确性分别为95．1％，100％和95．3％。其对瘤内血流的检出率（92．5％）与三相动态CT（97．2％，P＝0．14）和数字减影血管造影（88．9％，P＝0．53）相比无显著性差异，而较MRI的检出率（69．4％）高（P＝0．001）。结论：编码谐波声学造影能有效地检出小肝癌内的血流信号，并为早期诊断小肝癌提供重要信息。     

Carbon dioxide-enhanced ultrasonography of liver tumors.

CO2 gas-enhanced ultrasonography was performed in 37 patients (47 studies) for the purpose of detecting small tumors and evaluating differential diagnosis. With conventional ultrasonography, 62 lesions were identified in 25 patients with HCC, 13 tumors were identified in eight patients with hemangioma, and multiple tumors were found in four patients with metastatic adenocarcinoma. CO2-enhanced ultrasonography detected five additional hemangiomas, 12 additional nodules in HCC, and the same number of metastatic nodules. The patterns of CO2 enhancement were characterized as homogeneous, heterogeneous, rim, internal spotted, negative, and mixed (more than one pattern in one lesion). The rim enhancement pattern was found to be specific for hemangioma. The internal spotted enhancement pattern was found exclusively in HCC. All the lesions that demonstrated negative enhancement were treated HCC. All the metastatic tumors demonstrated the mixed rim and internal spotted enhancement pattern. We suggest that CO2-enhanced ultrasonography is a useful tool in detecting small liver tumors. It can also help in the differentiation among various hepatic tumors.     

Diagnosis of advanced hepatocellular carcinoma using contrast-enhanced harmonic gray-scale imaging with enhancement agents (Levovist): Correlation with helical CT and US angiography

We compared contrast-enhanced harmonic gray-scale imaging with helical CT and US angiography to evaluate vascularity in advanced hepatocellular carcinoma (HCC). Contrast-enhanced harmonic gray-scale imaging using Levovist (Nihon Schering, Tanabe) as the contrast agent and enhanced helical CT were performed on 38 patients with 45 lesions (29 men and 9 women aged 41 to 83 years; mean age, 66 years; mean maximum tumor diameter, 30.5±23.0 mm), and angiography was performed to evaluate 37 lesions from 32 of these 38 patients (24 men and 8 women, aged 41 to 79 years; mean age, 65 years; mean maximum tumor diameter, 27.9±17.9 mm). Contrast-enhanced harmonic gray-scale imaging showed hypervascular enhancement in 41 of the 45 lesions; the other 4 lesions were not visualized as hypervascular because 3 of the them could not be detected with non-enhanced US and the remaining lesion was situated deep in the liver and more than 11 cm from the surface of the body. Helical CT showed areas of high attenuation in 40 of the 45 lesions, leaving the other 5 lesions equivocal, while US angiography achieved positive enhancement in 36 of 37 lesions. Intratumoral vessels were visualized with contrast-enhanced harmonic gray-scale imaging in 25 of the 45 lesions; however; intratumoral vessels were seen in only 4 of the 45 lesions examined with helical CT. In evaluating vascularity in advanced HCC, contrast-enhanced harmonic gray-scale imaging with Levovist was as effective as US angiography and more effective than helical CT. Motion artifacts produced by the heart make it difficult to evaluate vascularity in advanced HCC located in the left lobe of the liver with Doppler sonography. Contrast-enhanced harmonic gray-scale imaging can show intratumoral vessels and hypervascular enhancement of the tumor without motion artifacts, however, even when the tumor is located near the heart or large vessels. Contrast-enhanced harmonic gray-scale imaging is useful for evaluating vascularity in advanced HCC when the tumor can be visualized with non-enhanced US.     

Seeding from hepatocellular carcinoma after percutaneous ablation: color Doppler ultrasound findings

Background We describe the clinical and color Doppler ultrasound findings in a series of cases of seeding from hepatocellular carcinoma (HCC) observed in patients treated with percutaneous ablation therapy (PAT) over a 15-year period. Methods We reviewed the clinical and imaging records of 12 patients with cirrhosis (nine men and three women, age range 51–82 years, mean age 63 years) that showed neoplastic seeding from HCC occurring after one or more PAT procedures. Five of 12 cases of seeding were observed as a complication of 1080 PAT procedures (0.46%) performed in 545 patients (0.96%) by two of the authors (L.T., G.F.) over a long period (15 years) at different institutions. The other seven patients had been treated with PAT procedures at other institutions and had come to our attention during post-treatment follow-up. Results The 12 patients who had seeding nodules had undergone the following PAT procedures: multisession conventional percutaneous ethanol injection (PEI) without anesthesia (four patients), single-session PEI with general anesthesia (three patients), single-session PEI with general anesthesia plus multisession conventional PEI (four patients), and single-session PEI plus radiofrequency ablation (one patient). Seeding nodules ranged from 0.9 to 6.0 cm (mean 1.7 cm). Eleven of 12 seeding nodules appeared as hypervascular hypoechoic nodules with smooth and regular margins and multiple intralesional vascular signals. Conclusions Clinical and imaging findings of seeding from HCC should be recognized by physicians who perform follow-up ultrasound examinations of patients who are treated with PAT. Early diagnosis of seeding can be reliably made by scanning the abdominal wall with small probes in the area where the previous PAT has been performed. Hypoechoic hypervascular pattern of the seeding nodule allows definitive diagnosis.     

High-intensity focused ultrasound ablation assisted using color Doppler imaging for the treatment of hepatocellular carcinomas

Purpose

We evaluated the usefulness of color Doppler flow imaging to compensate for the inadequate resolution of the ultrasound (US) monitoring during high-intensity focused ultrasound (HIFU) for the treatment of hepatocellular carcinoma (HCC).

Materials and methods

US-guided HIFU ablation assisted using color Doppler flow imaging was performed in 11 patients with small HCC (<3 lesions, <3 cm in diameter). The HIFU system (Chongqing Haifu Tech) was used under US guidance. Color Doppler sonographic studies were performed using an HIFU 6150S US imaging unit system and a 2.7-MHz electronic convex probe.

Results

The color Doppler images were used because of the influence of multi-reflections and the emergence of hyperecho. In 1 of the 11 patients, multi-reflections were responsible for the poor visualization of the tumor. In 10 cases, the tumor was poorly visualized because of the emergence of a hyperecho. In these cases, the ability to identify the original tumor location on the monitor by referencing the color Doppler images of the portal vein and the hepatic vein was very useful. HIFU treatments were successfully performed in all 11 patients with the assistance of color Doppler imaging.

Conclusion

Color Doppler imaging is useful for the treatment of HCC using HIFU, compensating for the occasionally poor visualization provided by B-mode conventional US imaging.     

Power Doppler sonography of hepatocellular carcinomas with portal-vein blood supply

We report the power Doppler imaging (PDI) findings in 2 cases of hepatocellular carcinoma (HCC) with a portal-vein blood supply. Gray-scale sonography in both cases showed a well-circumscribed nodule, hypoechoic in case 1 and hyperechoic in case 2. PDI revealed an afferent tumor vessel with constant flow in both nodules, and CT during arterial portography demonstrated a portal-vein supply to both nodules. The nodules were diagnosed by percutaneous core biopsies as highly differentiated HCC. We also examined with PDI another 64 patients with 76 HCC nodules, and none of the nodules showed a constant-flow afferent tumor vessel. The presence of a constant-flow afferent tumor vessel indicates a supplying portal vein; but this is not diagnostic of HCC, and biopsy remains necessary to establish a final diagnosis.     

Hepatocarcinogenesis: imaging-pathologic correlation

Rapid advances in liver surgery, including liver transplantation, radiology, and pathology, have created a need for clinically relevant nomenclature for premalignant and early lesions of hepatocellular carcinoma (HCC). Precancerous lesions include dysplastic foci and dysplastic nodules (DNs) characterized by cytologic or structural atypia. Although imaging diagnosis is playing a crucial role in the evaluation of hepatocarcinogenesis and early diagnosis of HCC, it is still challenging to accurately characterize borderline nodules such as small arterially enhancing lesions or hypovascular nodules. This article discusses pathological and radiological features of these small nodular lesions and offers insights into the multistep process of hepatocarcinogenesis by describing the progression of pathologic change linking DNs to HCC.     

超声造影与增强MRI对高分化肝癌和异型增生结节的诊断

目的探讨超声造影与增强MRI对高分化肝细胞癌和肝异型增生结节（DN）的诊断能力。 方法回顾性收集2012年1月至2018年12月在复旦大学附属中山医院同期行超声造影和增强MRI检查并获病理学证实的39例患者的39个高分化肝细胞癌病灶和7例患者的8个DN病灶，分析其超声造影和增强MRI表现特征。采用χ²检验，计算Kappa值，比较2种检查方法的诊断一致性；绘制不同检查方法的受试者操作特征（ROC）曲线，分析其诊断效能。 结果2种诊断方法中，69.2%（27/39）的高分化肝细胞癌的动脉期表现一致（Kappa=0.482），53.8%（21/39）的高分化肝细胞癌的延迟期表现一致（Kappa=0.168）。DN病灶在超声造影的主要表现呈“等增强-等增强”模式（87.5%，7/8），增强MRI主要表现为“高信号-低信号”模式（62.5%，5/8），所有DN病灶在超声造影延迟期均未出现廓清。超声造影、增强MRI、超声造影联合增强MRI（同时满足或只满足一种）4种检查方法中，超声造影联合增强MRI（只满足一种）诊断高分化肝细胞癌的敏感度（66.7%）和准确性（61.7%）最高，而超声造影诊断高分化肝细胞癌的特异度（100%）和ROC曲线下面积（0.658，95%CI：0.482~0.834）最高。 结论超声造影联合增强MRI有助于高分化肝细胞癌和肝DN的鉴别诊断，而超声造影具有更高的诊断特异度。     

Imaging of HCC

Imaging techniques play a crucial role in the management of patients with liver cirrhosis in whom a nodular hepatic lesion is detected. The most severe complication of patients with liver cirrhosis is the development of a hepatocellular carcinoma (HCC), and the prognosis of the disease depends on the tumoral stage. Surveillance programs based on ultrasonography (US) are recommended in cirrhotic patients with possibility to be treated if an HCC is detected, in order to improve the patient’s survival. Nevertheless, early detection and diagnostic confirmation of HCC remains a challenge despite technological advances. The non-invasive criteria to characterize small HCCs in patients with cirrhosis are based on the evaluation of the vascular profile of the lesion. Dynamic multidetector computed tomography (MDCT) and dynamic magnetic resonance imaging (MRI) are the suitable techniques for this purpose. When diagnosis is not achieved, fine US-guided fine needle biopsy (FNB) is indicated. Cellular-MRI contrast agents may have a role in lesions with atypical vascular pattern in which FNB is not feasible. The assessment of the disease extent is another important goal for imaging techniques. Again, dynamic MDCT and dynamic MRI may be used for staging purposes. Although MRI is more accurate in the detection of additional nodules ranging 1–2 cm, both remain relatively insensitive for the detection of tiny satellite nodules below 1 cm. The therapeutic decision can be made in any particular patient on the basis of the tumoral extension, the liver function, and the general status. After curative and palliative therapeutic procedures, the monitoring of the response is mandatory to decide the next approach: to follow-up, to repeat the treatment, to modify the treatment indication, or to suspend the treatment. In this review, we discuss the most recent information on the imaging of HCC.     

Tumor cell proliferation of hepatocellular carcinoma, with special reference to ultrasonographic findings and arterial vascularity by US angiography

Introduction  To determine the clinical significance of tumor-cell proliferation in hepatocellular carcinoma (HCC), we investigated the relationship between tumor-cell proliferation evaluated by Ki-67 labeling index and ultrasonographic findings and degree of arterial vascularity evaluated by US angiography in patients with HCC. Methods  HCC cells from 70 histologically confirmed HCC nodules obtained at biopsy of 64 patients were immunohistochemically studied for Ki-67 labeling index. We compared such corresponding ultrasonographic findings as tumor diameter, halo, and internal echo pattern, and the degree of arterial vascularity on US angiography. Arterial vascularity was then classified into three grades based on the findings of digital subtraction angiography (DSA) and US angiography. Results  Nodule diameter greater than 3 cm, presence of halo, or presence of internal echo with a mosaic pattern, alone or in combination, indicated enhanced proliferation of tumor cells. Although enhanced proliferation of tumor cells was seen in nodules with a stron arterial vascularity that could be detected by DSA, proliferation was not enhanced in nodules with a weak arterial vascularity that could be detected only by US angiography. Conclusion  HCC with weak arterial vascularity detectable only by US angiography may show a lower grade of biological malignancy, suggesting that prognosis is improved by early diagnosis and treatment of these lesions.     

SPIO联合Gd-DTPA增强对大鼠肝癌结节诊断价值研究

目的探讨超顺磁性氧化铁(SPIO)联合钆剂(Gd-DTPA)增强对诱发大鼠肝硬化肝癌结节的诊断价值。方法Wistar大鼠50只(实验组n=40,对照组n=10),前者饮水中加入二乙基亚硝胺到第12周,第13~19周随机抽取大鼠进行SPIO联合Gd-DTPA增强扫描,取大于3mm结节送病理,区分肝硬化(RNs)和肝癌(HCC)结节;比较两种对比剂增强的肿瘤检出率,结果进行χ2检验。结果106个结节中RNs24个,HCC82个,SPIO、Gd-DTPA增强肿瘤检出率分别为95.12%、89.02%,SPIO肿瘤检出率高于Gad-DTPA(P>0.05)。结论SPIO较Gd-DTPA增强更易检出肝癌结节,SPIO联合Gad-DTPA增强对肝硬化、肝癌结节定性诊断有互补作用。     

Does second harmonic imaging improve left ventricular endocardial border identification at higher heart rates during dobutamine stress echocardiography?

BACKGROUND: The increased heart rate during dobutamine stress echocardiography (DSE) may impair endocardial border visualization. Second harmonic imaging (SHI) enhances left ventricular (LV) border visualization compared with conventional fundamental imaging (FI) at rest. However, its role during DSE is not well established yet. OBJECTIVE: Our objective was to compare the additional value of SHI to FI for the LV endocardial border visualization during various stages of DSE. METHODS: Eighty patients underwent DSE. Imaging was performed with both FI and SHI at rest and at low-and peak-dose dobutamine infusion. Endocardial border visualization was assessed by using a 16-segment/3-point score (0 = well visualized; 1 = poorly visualized; 2 = not visualized). RESULTS: Heart rate increased from rest (70 +/- 13 bpm) to low-dose dobutamine (77 +/- 17, P <.01) and showed further increase at peak dose (129 +/- 16, P <.001 versus low dose). There was a higher prevalence of segments with an invisible LV endocardial border with FI compared with SHI at rest (9.4% versus 6.2%, P <.0001), at low dose (10.8% versus 6.3%, P <.0001), and at peak dose (15.0% versus 8.2%, P <.0001). There was an increase in the number of segments with an invisible border from rest to peak stress by FI (P =.0001), whereas the difference was less significant for SHI (P =.07). CONCLUSION: Second harmonic imaging improves visualization of the LV endocardial border compared with FI during DSE. The advantage of SHI over FI is more marked at higher heart rates than at rest.     

Budd-Chiari综合征合并肝脏结节的声像图及超声造影表现

目的 探讨Budd-Chiari综合征(BCS)合并肝脏结节患者的声像图及超声造影表现.方法 对30例BCS合并肝脏结节的患者行彩色多普勒超声及超声造影检查.结果 9例BCS患者肝内结节为肝细胞性肝癌(HCC)结节,结节多单发且直径多大于30 mm,超声造影表现为典型"快进快出"模式.21例为再生结节,结节多发,直径小于30 mm.根据再生结节内部回声、肝内分布情况以及造影模式将结节分为3型.Ⅰ型13例,肝内结节回声均匀,散在分布,超声造影3个时相均为等增强;Ⅱ型6例,结节中央为等回声或高回声,周边为低回声,超声造影动脉相呈中央离心型增强,门脉相及延迟相始终呈整体高增强;Ⅲ型2例,结节内为等回声或稍高回声,呈聚集状分布于门脉周围,超声造影动脉相呈周边向心型增强,门脉相及延迟相周边呈环状高增强.Ⅱ型和Ⅲ型均呈"快进慢出"模式.结论 BCS合并不同性质的肝脏结节其声像图及超声造影表现不同,超声对鉴别结节性质有重要价值.     

超声自然组织谐波成像在胆囊隆起性病变中的应用价值

目的 通过与常规超声即基波成像的对比观察,旨在探讨自然组织谐波成像在胆囊隆起性病变中的应用价值.方法 采用数字式超声诊断仪对比分析62例胆囊隆起性病变基波成像和自然组织谐波成像结果.结果 62例胆囊隆起性病变中胆囊壁总清晰度在自然组织谐波成像为100%,而基波成像为72.6%,二者呈显著差异（P＜0.01）,11例基波成像示胆囊底部有伪影,改为自然组织谐波成像伪影消失.结论 自然组织谐波成像对胆囊隆起性病变的超声图像能明显改善信噪比和分辨率,提高二维图像质量,具有极高的诊断价值.