Focal nodular hyperplasia and hepatocellular adenoma of the liver: differentiation with multiphasic helical CT

OBJECTIVE: Differences of attenuation and enhancement patterns in focal nodular hyperplasia and hepatocellular adenoma were evaluated and quantified using triphasic single-slice helical CT. MATERIALS AND METHODS: Forty-five histologically proven focal nodular hyperplasias in 27 patients and 18 hepatocellular adenomas in six patients were examined with helical CT. Quantitative evaluation included the following: attenuation of lesions, scar, and liver parenchyma during unenhanced, arterial (20 sec after injection), and portal venous phases (70 sec after injection); relative enhancement of lesions and liver (the ratio between attenuation in arterial phase and portal venous phase, respectively, and attenuation in unenhanced phase); and the prevalence of scar and its central vessel in focal nodular hyperplasia. RESULTS: The study showed no significant difference between mean attenuation values of focal nodular hyperplasia (mean +/- SD, 51.2 +/- 5.9 H) and hepatocellular adenoma (mean +/- SD, 56.3 +/- 7.8 H) in the unenhanced phase. In the arterial phase attenuation values were significantly higher in focal nodular hyperplasia (mean +/- SD, 117.9 +/- 15.1 H) than in hepatocellular adenoma (mean +/- SD, 80.1 +/- 10.5 H). In the portal venous phase no significant differences in attenuation values were detected between focal nodular hyperplasia (mean +/- SD, 112.1 +/- 20.4 H) and hepatocellular adenoma (mean +/- SD, 110.2 +/- 12.9 H). For enhancement parameter thresholds separating focal nodular hyperplasia from hepatocellular adenoma, the following were found: the relative enhancement was higher in 100% of the focal nodular hyperplasias and lower than or equal to 1.6 (accuracy, 96%) in 87% of the hepatocellular adenomas. CONCLUSION: Triphasic helical CT combined with quantitative evaluation of liver lesions offers the possibility of detecting differences in liver lesions that are visually similar on CT. The attenuation and relative enhancement in the arterial phase show significant differences that make accurate differentiation between focal nodular hyperplasia and hepatocellular adenoma possible.     

动态增强容积内插序列在肝脏占位性病变的临床应用价值

目的:评价MRI三维动态增强容积内插序列在肝脏局灶性病变的临床应用价值.方法:91例肝脏占位性病变患者进行常规MR T1WI和T2WI扫描后,采用三维扰相梯度序列行屏气全肝3期动态增强扫描并进行图像重组,观察病灶的增强特点,并对肝动脉的显示程度进行分级.结果:91例中原发性肝癌17例,肝血管瘤24例,肝转移性肿瘤16例,局灶性结节增生2例,肝脓肿11例,肝囊肿21例.肝动脉显示为2级86例94.5%,1级3例3.3%,0级2例2.2%.结论:MR 动态增强容积内插技术可以获得高质量的图像(尤其是动脉期),有利于肝脏局灶性病变的定性、定位诊断和指导临床治疗.     

Differentiation of focal nodular hyperplasia and hepatocellular adenoma by contrast-enhanced ultrasound

Non-invasive differentiation of focal nodular hyperplasia (FNH) and hepatocellular adenoma (HCA) is difficult. The aim of this study was to assess the accuracy of contrast-enhanced phase inversion ultrasound to differentiate between histologically proven FNH and HCA, analysing the arterial and (early) portal venous phase. 32 patients with histological proven FNH (n=24) or HCA (n=8) have been included in this prospective study. Examination technique: Siemens Elegra, phase inversion harmonic imaging (PIHI) with low mechanical index (MI)<0.2-0.3 using SonoVue (BR 1). The contrast enhancing tumour characteristics were evaluated during the hepatic arterial (starting 8-22 s) and early portal venous phase (starting 12-30 s). The image analysis was performed by three examiners. In 23 of 24 patients with FNH the contrast pattern revealed pronounced arterial and (early) portal venous enhancement. Homogeneous enhancement was detected during the hepatic arterial phase in all eight patients with HCA. In contrast to patients with FNH, no enhancement was seen during the portal venous phase. In conclusion, contrast-enhanced phase inversion ultrasound demonstrated pronounced arterial and portal venous enhancement in patients with focal nodular hyperplasia. In contrast, after homogeneous enhancement during hepatic arterial phase, no enhancement during hepatic portal venous phase was detected in patients with hepatocellular adenoma. Therefore, this technique might improve the functional characterization of benign hypervascular focal liver lesions.     

肝局灶性病变CT与MRI动态增强对照研究

目的:探讨肝局灶性病变在CT和MRI动态增强中的影像差异及其原因,以提高对CT及MRI各自动态增强表现的认识。方法:搜集17例肝脏局灶性病变患者的临床资料,其中7例肝细胞肝癌,5例海绵状血管瘤,2例腺瘤,2例局灶结节性增生,1例转移瘤。全部病例均分别行CT及MRI的平扫和三期动态增强扫描;MRI采用SE序列加快速扰相梯度回波序列,将CT和MR动态增强图像进行对照观察,包括动态增强各期的强化范围、强化方式和强化幅度,强化幅度的比较用病灶密度(信号)与肝脏密度(信号)的比值进行比较。结果:肝癌、腺瘤和局灶结节性增生在CT与MRI上强化范围相似。1例肝癌动脉期强化幅度MRI大于CT,3例肝癌和2例局灶结节性增生门脉期及延迟期强化幅度MRI大于CT,2例腺瘤增强各期强化幅度MRI均大于CT,以动脉期差异最大。5例海绵状血管瘤强化范围动脉期及门脉期MRI大于CT,延迟期则相仿。1例转移瘤CT增强各期均未见明显强化,MRI门脉期及延迟期可见环状强化。结论:肝局灶性病变CT与MRI动态增强表现存在一定的差异,主要表现为部分病变增强各期强化幅度MRI大于CT,尤以动脉期差异最大;部分病变增强范围MRI大于CT。     

Ultrasound of focal liver lesions

This paper gives a comprehensive overview of ultrasound of focal liver lesions. Technical aspects such as examination technique and the use of Doppler modes as well as recent developments such as tissue harmonic imaging and microbubble contrast agents are discussed. The clinical significance and sonographic features of various liver lesions such as haemangioma, focal nodular hyperplasia, adenoma, regenerative nodule, metastasis, hepatocellular carcinoma and various types of focal infections are described. With the exception of cysts and typical haemangiomas, definitive characterisation of a liver lesion is often not possible on conventional ultrasound. This situation has changed with the recent advent of ultrasound contrast agents, which permit definitive diagnosis of most lesions. Contrast-enhanced sonography using recently developed contrast-specific imaging modes dramatically extends the role of liver ultrasound by improving its specificity in the detection and characterisation of focal lesions to rival CT and MRI.     

Radiological and histopathological manifestations of hepatocellular nodular lesions concomitant with various congenital and acquired hepatic hemodynamic abnormalities

Congenital and acquired hepatic hemodynamic abnormalities are classified into four categories: hepatic arterial inflow disorder, portal vein inflow disorder, hepatic vein outflow disorder, and presence of a third inflow to the liver. Although their detailed etiology is not fully understood, these hepatic hemodynamic abnormalities may cause the formation of hepatocellular nodules. Recent advances in imaging modalities now enable visualization of these hepatocellular nodules concomitantly with the identification of various congenital and acquired hemodynamic abnormalities. Most of these nodular lesions are benign hyperplastic nodules, such as focal nodular hyperplasia, nodular regenerative hyperplasia, and other types of regenerative nodules. However, neoplastic nodules such as hepatic adenoma and hepatocellular carcinoma may also occur in conjunction with hepatic hemodynamic abnormalities. Distinguishing neoplastic nodules, especially malignant liver tumors, from hyperplastic nodules is important. Detection of intranodular Kupffer cells with superparamagnetic iron oxide enhanced magnetic resonance imaging is a key indicator that a nodule is regenerative rather than neoplastic.     

肝局灶性结节增生的多种影像学表现分析

目的分析肝局灶性结节增生(FNH)的CT、DSA及18FDG正电子发射体层摄影术(PET)的影像表现,认识FNH的多种影像学特征.资料与方法 10例FNH经手术病理证实,回顾分析其多种影像学表现.10例均行CT平扫及动态增强扫描,其中4例行DSA肝动脉造影,2例行18FDG PET显像.结果 10例FNH均为单发性结节,位于肝右叶8例,肝左叶2例.肿瘤直径1.1～9.3 cm,平均5.1 cm.CT检查10例,平扫均为低密度,其中8例病灶(直径均＞3.0 cm)中央区有星芒状的更低密度区;增强扫描,动脉期9个结节明显强化,1个中等强化,病灶中央更低密度区无强化,2个病灶中央或周边见增粗迂曲血管,其中1个尚可见动脉-门脉、动脉-静脉分流现象;门脉期病灶密度稍有下降,8个高于或等于肝实质,2个低于肝实质;延迟期7个等于或略高于肝实质,3个低于肝实质,5个病灶中央更低密度有强化.血管造影:4例FNH的供血动脉均来自肝动脉系统,供血动脉增粗、扭曲, 1例血管分支放射状分布,周围呈环绕状聚集染色,中央局限性缺损,另3个分支血管紊乱并呈抱球征,1个尚见动脉-门脉、动脉-静脉分流.2例18FDG PET显像均未见异常放射性浓聚.结论 FNH CT平扫为低密度,增强扫描以"快进慢出"为主要特征,而血管造影显示肝动脉供血为主,表现为供血动脉增粗、扭曲,呈轮辐状向周围发散.这些影像特征有利于FNH的定性诊断.     

X-ray diagnostic strategies in liver and pancreatic tumors

The following publication describes the diagnostic approach in different benign and malignant space-occupying lesions of the liver and pancreas. An essential prerequisite is that all imaging methods are actually available and can be made use of. While taking the cost factor into consideration, flow diagrams are worked out for haemangiomas, focal nodular hyperplasia, hepatocellular carcinoma and liver metastases, as well as for carcinoma of the pancreas and for insulinoma.     

The real capabilities of contrast-enhanced ultrasound in the characterization of solid focal liver lesions

Contrast-enhanced US (CEUS) using intravenous agents is a rapidly evolving field even though the main clinically recognized application is the characterization of focal liver lesions. Several reports have described the improvement provided by CEUS in the characterization of focal liver lesions in comparison to unenhanced US. CEUS with low transmit power insonation allows the real-time assessment of focal liver lesion contrast enhancement and vascularity during the different dynamic phases after injection of an intravenous contrast agent. CEUS allows the accurate characterization of focal liver lesions as benign or malignant based on the lesion contrast enhancement pattern during the arterial phase and lesion vascularity during portal--late phase in comparison to the adjacent liver parenchyma. During the portal--late phase, benign lesions present prevalently a sustained contrast enhancement with hyper or isovascular appearance to the adjacent liver while malignant lesions present prevalently microbubble washout with hypovascular appearance. On the other hand, the histology of focal liver lesions can only be confidently predicted in selected cases by CEUS, as in liver haemangiomas presenting typical nodular peripheral enhancement with subsequent centripetal fill-in and focal nodular hyperplasia with central spoke wheel-shaped contrast enhancement.     

肝胆特异性磁共振对比剂Gd-EOB-DTPA在肝脏局灶性病变诊断中的应用研究

目的:探讨Gd-EOB-DTPA MRI增强扫描时肝局灶性病变的表现及此新型对比剂的诊断效能,提高对肝脏局灶性病变的诊断准确性。方法:已知或怀疑为肝脏局灶性病变的34例患者共90个病灶,病灶性质依次为肝囊肿20个、肝细胞肝癌16个、胆管细胞癌1个、肝脏转移性肿瘤37个、肝血管瘤9个、退变结节1个、肝脏局灶性结节增生1个、肝细胞腺瘤1个、肝脏炎性病变3个及肝脏淋巴上皮瘤样癌1个。所有患者依次行MRI平扫(抑脂TSE T2WI、抑脂3DVIBE、2DGRE T1WI)、Gd-EOB-DTPA三期(动脉期、门脉期和平衡期)增强扫描(抑脂3DVIBE)及延迟20min肝实质期扫描(抑脂2DGRE T1WI、抑脂TSE T2WI、抑脂3DVIBE)。测量并分析Gd-EOB-DTPA增强前后肝脏和病灶信号变化、病灶-肝脏对比噪声比绝对值(|CNR|)变化情况,并观察病灶Gd-EOB-DTPA增强扫描表现和特征。结果:Gd-EOB-DT-PA增强后各期肝实质信号及病灶-肝脏|CNR|均显著增加(P<0.001)。动脉期、门脉期和平衡期所有病灶符合应用常规含钆(Gd)对比剂时的强化表现和特征;延迟20min肝实质期扫描时,肝脏局灶性结节增生呈等信号-高信号,1个肝细胞肝癌呈相对高信号,其余肝囊肿、肝细胞肝癌、胆管细胞癌、肝脏转移性肿瘤、淋巴上皮瘤样癌、退变结节、肝细胞腺瘤、肝血管瘤和肝脏炎性假瘤等均呈相对低信号。结论:Gd-EOB-DTPA动态增强扫描与延迟肝实质期扫描联合应用,可以提供病变形态、血供、细胞来源及功能等更多相关信息,从而提高诊断信心及诊断准确性。     

肝脏不典型腺瘤样增生结节的综合影像诊断

研究肝脏不典型腺瘤样增生结节的ＵＳ、ＣＴ和ＭＲＩ表现与诊断。方法回顾性分析经病理证实的７例（手术切除３例,ＵＳ引导下肝穿刺活检４例）肝脏不典型腺瘤样增生结节的ＵＳ、ＣＴ和ＭＲＩ表现,以及术前或穿刺前诊断情况,并与病理对照。结果５例诊断为癌前病变,２例误诊为小肝癌。ＵＳ显示稍低或等回声６例,稍强回声１例。     

Enhancement of focal liver lesions at gadoxetic acid-enhanced MR imaging: correlation with histopathologic findings and spiral CT--initial observations

PURPOSE: To detect hepatocyte-selective enhancement of focal lesions with gadoxetic acid at magnetic resonance (MR) imaging and to correlate enhancement in hepatocyte-selective phases with histopathologic findings and in arterial and portal venous phases with biphasic computed tomographic (CT) findings. MATERIALS AND METHODS: Study was supported by local ethics committee; all patients gave written informed consent. In 19 men and 14 women recruited in three clinical studies, histopathologic correlation and CT scans of 41 focal lesions (13 primary malignant lesions, 21 metastases, three adenomas, three cases of focal nodular hyperplasia [FNH], and one cystadenoma) and ultrasonographic confirmation of five cysts were available. MR was performed before and during arterial and portal venous phases and in hepatocyte-selective phases 10 and 20 minutes after injection of gadoxetic acid. Enhancement was evaluated in consensus by two observers. Enhancement pattern and morphologic features during arterial and portal venous phases were correlated between gadoxetic acid-enhanced MR and CT images by means of adjusted chi(2) test. RESULTS: Hepatocyte-selective uptake was observed 10 and 20 minutes after injection in FNH (three of three), adenoma (two of three), cystadenoma (one of one), and highly differentiated hepatocellular carcinoma (HCC [grade G1], two of four). Uptake was not detected in metastases (21 of 21), cholangiocarcinoma (three of three), combined hepatocellular cholangiocarcinoma (one of one), undifferentiated carcinoma (one of one), moderately or poorly differentiated HCC (grade G2-G3) (four of four), HCC (grade G1, two of four), adenoma with atypia (one of three), or cysts (five of five). During arterial and portal venous phases, there was high overall agreement rate of 0.963 between gadoxetic acid-enhanced MR and CT (simultaneous 95% confidence interval: 0.945, 0.981). CONCLUSION: Liver-specific enhancement of focal lesions is hepatocyte selective and correlates with various histopathologic diagnoses regarding presence of certain hepatocytic functions. Arterial and portal venous MR images obtained with gadoxetic acid are comparable to those of CT.     

Hypervascular hepatic focal lesions: spectrum of imaging features

Detection and characterization of liver lesions often present a diagnostic challenge to the radiologists. Liver lesions may be classified as hypovascular and hypervascular based on degree of hepatic arterial blood supply. Common hypervascular liver lesions include hemangioma, focal nodular hyperplasia, hepatocellular adenoma, hepatocellular carcinoma, fibrolamellar carcinoma, and metastases from primary tumors such as islet cell tumor, carcinoid, renal cell carcinoma, melanoma, and thyroid carcinoma. In this review article, we discuss the spectrum of imaging features of hypervascular liver lesions.     

超声造影诊断肝脏局灶性结节状增生的价值

目的：探讨超声造影诊断肝脏局灶性结节状增生的价值。材料和方法：回顾分析了11例肝脏局灶性结节状增生的超声造影表现。9例于造影后经超声引导穿刺确诊,2例经手术确诊。结果：11例病灶动脉期均快速显著增强。9例病灶动脉早期呈轮辐状增强,造影三期回声强于周边肝实质,实质期可见轮辐状低回声；2例病灶动脉早期快速增强,动脉期及门脉期回声强于周边肝实质,实质期回声与肝实质等同,未见轮辐状低回声。结论：超声造影所显示的肝脏局灶性结节状增生的增强特征,有助于临床诊断。部分病灶超声造影表现缺乏特异性,确诊仍需要结合其他影像学方法和穿刺活检。     

Primary hepatocellular lesions: imaging findings on state-of-the-art magnetic resonance imaging, with pathologic correlation

Magnetic resonance imaging is routinely used for the workup of patients with focal or diffuse liver disease, including primary hepatocellular lesions, storage diseases, metastatic liver disease, and diseases of the hepatobiliary tree. The most important magnetic resonance imaging sequences used for diagnostic imaging of the liver consist of T1-weighted sequences, T2-weighted sequences, and at least the arterial and delayed phases of dynamic gadolinium-enhanced imaging. This article provides an overview of magnetic resonance imaging of primary hepatocellular lesions and will describe the following: (1) the classification and etiology of primary hepatocellular lesions, including focal nodular hyperplasia, hepatocellular adenoma, and hepatocellular carcinoma; (2) the stepwise carcinogenesis of hepatocellular carcinoma in cirrhosis on magnetic resonance imaging; and (3) the typical imaging findings of primary hepatocellular lesions on magnetic resonance imaging, with differential diagnoses.     

Characterization of focal hepatic lesions with ferumoxides-enhanced T2-weighted MR imaging

OBJECTIVE: The purpose of this study was to evaluate whether ferumoxides-enhanced MR imaging of focal hepatic lesions provides distinctive signal intensity and lesion-to-liver contrast changes for benign and malignant lesions, helping to further characterize and differentiate these lesions. MATERIALS AND METHODS: Data analysis was performed on 70 patients, with previously identified focal hepatic lesions, who underwent MR imaging of the liver before and after IV administration of ferumoxides (10 micromol Fe/kg). Lesions analyzed with pathologically proven diagnoses included metastases (n = 40), hepatocellular carcinoma (n = 11), cholangiocarcinoma (n = 6), hemangioma (n = 4), focal nodular hyperplasia (n = 6), and hepatocellular adenoma (n = 3). Response variables measured and statistically compared included the percentage of signal-intensity change and lesion-to-liver contrast. RESULTS: Focal nodular hyperplasia showed significant signal intensity loss on ferumoxides-enhanced T2-weighted images (mean, -43%+/-6.7%, p < 0.01). All other lesion groups showed no statistically significant change in signal intensity on ferumoxides-enhanced T2-weighted images, although signal intensity loss was seen in some individual hepatocellular adenomas (mean, -6.6%+/-24.0%) and hepatocellular carcinomas (mean, -3.3%+/-10.3%). All lesions, with the exception of hepatocellular carcinoma, had a marked increase in lesion-to-liver contrast on ferumoxides-enhanced T2-weighted images, which was statistically significant for metastases and hemangioma (p < 0.02). CONCLUSION: Focal nodular hyperplasia shows significant decrease in signal intensity on ferumoxides-enhanced T2-weighted images, which may aid in the differentiation of focal nodular hyperplasia from other focal hepatic lesions. Other lesions, namely, hepatocellular adenoma and carcinoma, can have reticuloendothelial uptake, but usually to a lesser degree than that of focal nodular hyperplasia.     

Importance of evaluating all vascular phases on contrast-enhanced sonography in the differentiation of benign from malignant focal liver lesions

OBJECTIVE: Our objective was to evaluate the accuracy of a blood-pool sonographic contrast agent in the late phase compared with the three vascular phases for differentiation between benign and malignant focal liver lesions. SUBJECTS AND METHODS: In 152 patients (105 with chronic liver disease), 152 solid focal liver lesions characterized either by fine-needle biopsy or by dynamic CT or MRI were studied. The final diagnoses were metastasis for 24, hepatocellular carcinoma for 75, focal nodular hyperplasia for 13, regenerating or dysplastic nodule for 14, hemangioma for 22, cholangiocarcinoma for two, and another focal liver lesion for two. Real-time sonography was performed after a bolus injection of 2.4 mL of SonoVue, using a low mechanical index (< 0.2). All lesions were evaluated in the arterial, portal, and late phases; classified as benign or malignant; and correlated with final diagnoses. RESULTS: For discrimination between malignant and benign focal liver lesions, evaluation of all vascular phases improved the sensitivity from 78.4% to 98% and the accuracy from 80.9% to 92.7%, compared with evaluation of the late phase alone. The increase in accuracy was higher in patients with chronic liver disease (16.3%) than in those without (2.1%). CONCLUSION: Evaluation of SonoVue enhancement in all three vascular phases is superior to evaluation of SonoVue enhancement in the late phase alone, especially in patients with chronic liver disease.     

MSCT多期增强扫描对肝脏局灶性结节增生的诊断价值

目的:探讨MSCT多期增强扫描对肝脏局灶性结节增生(focal nodular hyperplasia,FNH)的诊断价值。方法:回顾性分析经手术及穿刺活检病理证实的9例FNH患者10个病灶的MSCT多期增强扫描表现。结果:9例中8例为单发病灶,1例多发。平扫9个呈低或稍低密度,1个等密度。平扫3个病灶见中央瘢痕;多期增强扫描7个病灶见中央瘢痕,动脉期及门脉期瘢痕均未见强化,延迟期5个见中央瘢痕强化。增强扫描动脉期除中央瘢痕外,8个FNH病灶明显均匀强化,2个中等均匀强化;门脉期病灶密度下降,但均略高于或等于正常肝实质;延迟期病灶密度等于或略低于肝实质。动脉期4个病灶中心或周边见增粗的供血动脉,其中1个为肝动脉分支直接进入病灶中心,1个的供血动脉自病灶中心沿纤维间隔向周边呈放射状分布,另2个周边见供血动脉。结论:MSCT多期扫描可反映病灶的血供特点和病理学特征,对FNH具有重要的诊断及鉴别诊断价值。     

Multidetector CT: contributions in liver imaging

Multidetector CT has had great impact in the evaluation of the liver. Increased speed combined with thin slice collimation improved the spatial and temporal resolution, which in turn provided a higher sensitivity in the detection of focal lesions, particularly for the hepatocellular cancer (HCC) in patients with cirrhosis. There is no consensus as to whether the so-called "double arterial phase scanning" improves the detection rate of hepatocellular cancers, and the majority of the more recent studies suggest acquiring only the late arterial phase images along with the portal venous phase images. However, if the patient is a surgical candidate, the early arterial phase images must also be obtained, because they provide better pre-surgical mapping of the hepatic arteries. In primary and metastatic liver tumors, arterial and portal venous phase images should be acquired with thin collimation and overlapping reconstruction. Maximum intensity projection and volume rendering methods demonstrate the three-dimensional anatomy of the hepatic arteries, portal and hepatic veins successfully, which provide useful information before hepatic resection or intraarterial chemotherapy. In living donor candidates, early arterial and portal venous phase images obtained with thin collimation and overlapping reconstruction are used to reconstruct three-dimensional images with maximum intensity and volume rendering methods. These have a high sensitivity to detect hepatic artery, portal and hepatic vein variations, which could render the surgery difficult or even impossible. Portal venous phase images can also be used to measure total and lobar liver volumes. A virtual hepatectomy plane can be simulated on the three-dimensional model of the liver and hepatic veins, and when necessary, its location can be modified according to the metabolic needs of the recipient and donor. Thin collimation and better temporal resolution may also have beneficial effects in the characterization of liver lesions.     

超声造影与彩色多普勒超声诊断肝实质性肿块对照研究

 目的 比较彩色多普勒超声和实时超声造影对肝实质性肿块的诊断价值.方法 应用彩色多普勒超声及超声造影技术对常规二维超声难以定性的27例共31个肝实质性肿块进行检查,结果与手术及病理结果相对照.结果 31个肿块中原发性肝细胞性肝癌24个,肝血管瘤3个,肝脏局灶性结节增生3个,肝孤立性坏死结节1个.彩色多普勒超声在肿块内部或肿块周边能检测到动脉血流频谱者共19例21个肿块;超声造影除一例肝孤立性坏死结节外,其余30个病灶均在不同时相出现不同程度强化现象.如以动脉相呈高回声而门脉相及延迟相呈低回声为恶性肿块的诊断标准,则超声造影对肝癌诊断的准确率为91.67%;如以肿块内部检测到动脉样血流频谱为诊断恶性肿块的诊断标准,则彩色多谱勒超声诊断肝癌的准确率为75%.超声造影诊断肝实质性肿块准确率为93.54%,彩色多普勒超声诊断肝实质性肿块准确率为64.52%.二者差别有统计学意义(P＜0.05).结论 实时超声造影显著提高肝内实质性肿块的诊断准确性,对肝脏实质性肿块良、恶性的诊断及鉴别诊断具有重要价值.