常规超声及超声造影参数对甲状腺乳头状癌被膜侵犯的评估

目的探讨常规超声及超声造影检查相关参数对评估甲状腺乳头状癌(PTC)被膜侵犯的应用价值。方法选取经手术病理证实的290例PTC患者共317个PTC结节,术前分别进行常规超声及超声造影定性定量检查,以病理结果癌结节有无被膜侵犯分组,回顾性比较常规超声及超声造影参数对判断被膜侵犯的价值。结果 317个癌结节中,经手术病理证实被膜侵犯为212个(66.88%),甲状腺癌结节大小、常规超声及超声造影条件下癌结节与被膜关系、结节动脉期灌注模式以及超声造影增强模式,在病理证实侵犯与未侵犯组之间差异具有统计学意义(P<0.05),多因素分析结果显示超声造影下癌结节与被膜接触、结节动脉期灌注模式表现为向心性增强以及超声造影表现为等增强及高增强与被膜侵犯相关(P<0.05)。结论常规超声检查及超声造影有助于判断甲状腺乳头状癌被膜是否侵犯,对临床应用具有一定的指导价值。     

高频超声术前预测甲状腺乳头状癌被膜外侵犯

目的 探讨高频超声术前预测甲状腺乳头状癌（PTC）被膜外侵犯（ETE）的临床价值。方法 收集经手术治疗的PTC患者116例,共151个结节,回顾性分析其声像图特点,观察结节与甲状腺被膜邻接长度占结节周长百分比（A）,分析以A≥1%、A≥25%及A≥50%预测PTC ETE的诊断效能。结果 151个PTC中,手术病理证实59个（59/151,39.07%）有被膜外侵犯（ETE组）,92个（92/151,60.93%）无被膜外侵犯（non-ETE组）。超声发现结节位于甲状腺实质内（A0）84个（84/151,55.63%）,1%≤ A< 25%、25%≤ A< 50%、A≥50%分别有25个（25/151,16.56%）、15个（15/151,9.93%）、27个（27/151,17.88%）。A≥1%、A≥25%、A≥50%的结节个数在ETE组和non-ETE组比较差异均有统计学意义（P均<0.01）。以A=50%为截断值,诊断PTC被膜外侵犯的敏感度、特异度、准确率、阳性预测值、阴性预测值分别为37.29%（22/59）、94.57%（87/92）、72.19%（109/151）、81.48%（22/27）、70.16%（87/124）。结论 高频超声可有效预测PTC有无ETE,为术前合理选择手术方式及对患者预后评估提供重要参考信息。     

超声造影及BRAF基因突变在甲状腺乳头状癌被膜外侵犯诊断中的应用价值

目的：探讨超声造影（CEUS）及BRAF基因突变在甲状腺乳头状癌（PTC）被膜外侵犯术前诊断中的价值。 方法：入组119名患者共129个PTC病灶，其中25个经术后病理证实存在甲状腺被膜外侵犯。记录传统超声（US）及CEUS模式下PTC与被膜接触范围、是否出现被膜中断现象，以及患者BRAF基因突变检测结果。计算上述特征单独及联合诊断PTC被膜外侵犯的效能。 结果：被膜外侵犯组BRAF基因突变阳性率、US及CEUS被膜接触范围及被膜中断率均显著高于无侵犯组（P<0.05）。接触范围中，US及CEUS均以?25%为界值诊断被膜外侵犯准确度最高。在各超声特征单独及联合BRAF基因突变用于诊断时，CEUS准确度均高于US，CEUS联合BRAF准确度88.38%。 结论：PTC被膜外侵犯临床、超声特征包括：BRAF基因突变阳性、US及CEUS显示结节与被膜接触?25%及被膜中断。CEUS诊断准确度高于US。CEUS联合BRAF基因突变在术前诊断PTC被膜外侵犯中具有重要意义。     

经直肠多模态超声影像评分系统诊断前列腺癌的临床研究

目的建立前列腺癌多模态超声影像评分系统,并评价该评分系统对前列腺癌的诊断价值。 方法选取2016年5月至2017年12月在解放军总医院行超声引导下穿刺活检和（或）手术切除的86例可疑前列腺癌患者,术前对前列腺行经直肠常规超声、剪切波弹性成像、超声造影检查,分析三种模态超声影像特征,并与手术或穿刺病理进行对照。总结前列腺癌经直肠多模态超声影像特征,建立评分系统,并评价该系统对前列腺癌的诊断价值。 结果前列腺癌常规超声表现为低回声、边界不清、形态不规则、内外腺分界不清、包膜侵犯、血流信号丰富且为中心血流;剪切波弹性成像表现为非对称分布,前列腺癌病灶平均弹性模量高于良性病灶［（94.7±44.2）kPa vs（60.8±26.0）kPa］,差异有统计学意义（t=-3.578,P=0.001）;超声造影表现为快速高增强,分布不均匀（低增强区伴点状血管结构,点状、片状或结节状高增强）,内外腺分界不清,包膜或直肠壁侵犯。常规超声、超声造影、弹性成像有1项阳性即诊断为前列腺癌,其敏感度、阴性预测值和准确性分别为98.0%、96.7%和89.5%;三者均为阳性诊断为前列腺癌,其特异度和阳性预测值分别为97.3%和97.1%。 结论经直肠多模态超声影像评分系统可提高超声对前列腺癌的诊断价值。     

甲状腺微小乳头状癌被膜外侵犯的超声评估

目的探讨超声征象对甲状腺微小乳头状癌(PTMC)被膜外侵犯的预测能力。方法收集经手术治疗的PTMC患者62例,共77个结节,根据术后病理将患者分为无被膜外侵犯组(non-ETE)和有被膜外侵犯(ETE)组。回顾分析声像图特点,探讨其预测PTMC存在被膜外侵犯的能力。结果 non-ETE组43例、55(71.43%)个结节,ETE组19例、22(28.57%)个结节。结节紧邻甲状腺被膜在non-ETE组(8/55)和ETE组(19/22)比较差异有统计学意义(P=0.000),该超声征象诊断PTMC存在被膜外侵犯的灵敏度、特异度、准确度、阳性预测值、阴性预测值分别为94.00%、70.37%、85.71%、85.45%和86.36%。甲状腺被膜连续性中断或消失在non-ETE组(3/55)和ETE组(15/22)比较,差异亦有显著统计学意义(P=0.000),其诊断PTMC存在被膜外侵犯的灵敏度、特异度、准确度、阳性预测值、阴性预测值分别为83.33%、88.14%、87.01%、68.18%和94.55%。上述两项超声指标联合诊断PTMC存在被膜外侵犯的ROC曲线下面积为0.885(0.790~0.981)。结论应用超声观察结节与甲状腺被膜的关系以及被膜的完整性对判断PTMC是否存在被膜外侵犯具有重要价值。     

超声造影联合超声实时组织弹性成像在甲状腺良恶性结节诊断中的应用价值

目的：评价超声造影联合超声实时组织弹性成像（RTE ）在甲状腺良恶性结节诊断中的应用价值。方法分析85例甲状腺结节患者的超声造影和RTE的图像信息并与病理活组织检查（活检）相对比,评估单用两种方法及联合使用两种方法诊断的灵敏度、特异度、阳性预测值、阴性预测值及诊断符合率。结果85个甲状腺结节中,病理活检证实恶性病灶48个,良性病灶37个。恶性结节在注射造影剂后以不均匀低增强为主,早于周边甲状腺组织消退。良性结节则以弥散性等增强或高增强为主,晚于周围腺体廓清。超声造影的灵敏度、特异度、阳性预测值、阴性预测值及诊断符合率分别为91.67％、81.08％、91.67％、81.08％、87.06％;RTE 则分别为87.50％、83.78％、87.50％、83.78％、85.89％;两者联合诊断的灵敏度、特异度、阳性预测值、阴性预测值及诊断符合率分别为97.92％、86.49％、90.38％、96.97％、92.94％。超声造影联合 RTE 灵敏度、特异度、阴性预测值及诊断符合率比单用超声造影或RTE高（均P＜0.05）。结论超声造影联合RTE可提高甲状腺良恶性结节诊断的准确性。     

甲状腺乳头状癌超声造影定量参数与微血管密度的相关性

目的 探讨甲状腺乳头状癌（PTC）超声造影定量参数与病理微血管密度（MVD）的相关性。方法 回顾性分析33例PTC患者（共36枚结节）术前常规超声及超声造影检查的声像图资料。应用Qlab软件绘制结节边缘及中心区域时间-强度曲线（TIC），获得不同部位的超声造影定量参数值，包括峰值强度和曲线下面积；术后对标本均进行CD31因子免疫组化染色，并分别计算结节边缘区域及中心区域的MVD，并分析上述超声造影定量参数与MVD的相关性。结果 PTC结节整体呈不均匀低增强，结节边缘区域增强程度多高于中心区域。PTC结节边缘区域RT、PI、AUC及MVD分别为（3.24±2.10sec、7.84±2.55dB、182.63±87.83dB sec、35.09±9.61条/HP），均高于结节中心（2.42±1.93sec、4.01±2.36dB、89.90±54.67dB sec、15.97±6.07条/HP），差异均有统计学意义（均P＜0.05）。PTC结节边缘区域的峰值强度和曲线下面积与边缘区域MVD均呈正相关（r= 0.831，P=0.000；r= 0.705，P=0.000）；PTC结节中心区域的峰值强度和曲线下面积与中心区域MVD之间均呈正相关（r= 0.678，P=0.000；r= 0.684，P=0.000）。结论 PTC结节的超声造影定量参数峰值强度和曲线下面积能反映PTC不同部位组织的MVD，CEUS可作为术前评估PTC结节MVD的无创性方法。     

超声造影及弹性成像技术对超声造影无增强甲状腺结节良恶性的鉴别诊断价值

目的探讨超声造影及实时剪切波弹性成像技术（SWE）对超声造影无增强甲状腺结节良恶性的鉴别诊断价值。 方法选取2018年1月至2019年6月在解放军总医院行甲状腺结节超声造影检查，病灶呈无增强表现，且病灶均行SWE检查的患者100例，所有患者均经穿刺活检或手术取得病理结果，依据病理结果将患者分为良性组和恶性组。分析比较2组病灶的超声造影特征及弹性模量最大值（Emax）、弹性模量平均值（Emean），并应用四格表和ROC曲线分析超声造影及SWE对甲状腺结节良恶性的诊断效能。 结果良性组与恶性组间无增强边界、结节整体完全无增强及Emax、Emean值差异均有统计学意义（P均<0.05），边界清晰主要见于良性组，边界不清主要见于恶性组，结节整体完全无增强则全部见于良性组，恶性组的Emax、Emean值均高于良性组。以病理结果为"金标准"，超声造影表现为无增强、边界不清诊断恶性甲状腺结节的敏感度、特异度、阴性预测值、阳性预测值分别为56%、75%、90%、30%；超声造影表现为整体完全无增强诊断良性甲状腺结节的敏感度、特异度、阴性预测值、阳性预测值分别为20%、100%、19%、100%。ROC曲线显示，Emax诊断恶性甲状腺结节的曲线下面积为0.696，以Emax>45.0 kPa为截断值时，其诊断敏感度和特异度分别为62.5%、64.3%；Emean诊断恶性甲状腺结节的曲线下面积为0.705，以Emean>47.7 kPa为截断值时，其诊断敏感度和特异度分别为56.3%、94.0%。 结论甲状腺结节超声造影呈无增强时，是否边界清晰及是否整体完全无增强可用于鉴别结节良恶性；SWE对于超声造影无增强甲状腺结节良恶性的鉴别诊断具有一定的价值，二者结合应用可指导临床减少不必要的穿刺活检及手术治疗。     

超声造影对甲状腺良恶性结节的诊断价值

目的探讨超声造影对甲状腺良恶性结节的诊断价值。方法对常规超声检出但定性诊断困难的69个甲状腺实性结节行超声造影检查,与手术病理结果对照,分析良恶性结节的增强模式,即造影剂进入结节时间、方式、增强程度、造影剂分布是否均匀以及结节内造影剂消退快慢的情况。结果超声造影表现:63.9%(23/36)甲状腺良性结节表现为等增强或高增强,84.8%(28/33)甲状腺癌表现为低增强或等增强。低或等增强、不均匀增强、早期消退对甲状腺乳头状癌的诊断敏感性分别为72.7%、87.9%、84.8%,良恶性结节的峰值强度、始增时间、达峰时间差异无统计学意义,但恶性结节消退时间早于良性结节(P0.05)。结论超声造影能为甲状腺结节良恶性鉴别诊断提供更有效的诊断方法。     

常规超声及应变弹性成像技术对细胞学诊断不确定甲状腺结节的诊断价值

目的 探讨常规超声和应变弹性成像对细胞学诊断不确定（即Bethesda Ⅲ、Ⅳ、Ⅴ类）甲状腺结节的诊断价值。方法 对有病理结果证实的细胞学诊断为Bethesda Ⅲ、Ⅳ、Ⅴ类的135个结节的常规超声及弹性图像进行回顾分析，比较细胞学诊断不确定的良恶性结节的超声特征差异，比较常规超声及其联合弹性成像对细胞学不确定的甲状腺结节恶性风险的评估能力。结果 135个结节中，112个（83%）结节手术病理为恶性，23个（17%）结节手术病理为良性。常规超声征象预测细胞学不确定恶性结节的敏感性，特异性，准确性，阳性预测值及阴性预测值分别为 95.54%，56.52%，88.89%，91.45%及72.22%，而常规超声联合弹性评分≥3分预测细胞学不确定恶性结节的敏感性，特异性，准确性，阳性预测值及阴性预测值分别为98.21%，30.43%，86.67%，87.3% 及77.78%。联合弹性成像，常规超声的诊断效能降低（P=0.03）。结论 常规超声及弹性成像在细胞学诊断不确定结节良恶性鉴别诊断方面有价值。但是联合弹性成像，未能提高常规超声特征对细胞学诊断不确定结节中恶性肿瘤的预测能力。     

Real-time contrast-enhanced ultrasound imaging of infected focal liver lesions.

OBJECTIVE: The purpose of this study was to investigate the features of infected focal liver lesions on contrast-enhanced ultrasound (CEUS) imaging. METHODS: Thirty-two hepatic abscesses, 15 infected granulomas, and 6 inflammatory pseudotumors in 53 patients were evaluated with real-time CEUS before awareness of the definitive diagnosis. A 2.4-mL dose of a sulfur hexafluoride-filled microbubble contrast agent was administered by intravenous bolus injection. RESULTS: The numbers of abscesses with hyperenhancement, isoenhancement, and hypoenhancement in the arterial phase were 26 (81.3%), 5 (15.6%), and 1 (3.1%), respectively. Thirty (93.8%) lesions were irregularly rim enhanced with nonenhanced areas; enhanced septa were shown in 22 (68.8%) lesions; and transient hyperenhancement of liver parenchyma around the lesion was shown in 20 (62.5%). In 31 abscesses with hyperenhancement or isoenhancement in the arterial phase, 25 (80.6%) showed contrast wash-out and changed in appearance to hypoenhancement in the late phase. As for infected granulomas and inflammatory pseudotumors, 16 (76.2%) lesions showed hyperenhancement or isoenhancement in the arterial phase, and all of them were hypoenhanced in the portal and late phases. CONCLUSIONS: Most infected focal liver lesions showed more rapid contrast wash-out than the surrounding liver parenchyma, which is similar to malignant lesions. Abscesses typically showed features of rim enhancement, enhanced internal septa, nonenhanced central necrotic areas, and transient hyperenhanced liver parenchyma around the lesions. The CEUS appearance of infected granulomas and inflammatory pseudotumors was variable, and a biopsy was necessary for definitive diagnosis.     

实时超声造影鉴别诊断肝脏瘤样病变

目的应用CEUS评价肝脏瘤样病变的血流灌注特征。方法选择35例瘤样病变患者(41个病灶)作为研究对象,21例经手术证实,14例经增强CT/MRI或随访证实。结果肝局灶性结节增生(FNH)13例,动脉相100%(13/13)高增强,动脉相早期10例呈中心向周边轮辐样强化,3例为从中心向周边强化范围逐渐扩大,周边出现一过性未强化带;门脉相100%(13/13)呈均匀高增强,延迟相84.62%(11/13)等或高增强,15.38(2/13)中心部低增强。肝孤立性坏死结节(SNN)12例,三相均未见强化,病灶大小、数目不一,形态各异。肝炎性假瘤(IPL)4例,动脉相高增强,门脉相低增强。肝局灶性脂肪变(FFC)6例,动脉相33.33%(2/6)高增强,16.67%(1/6)低增强,50.00%(3/6)等增强,门脉相及延迟相呈等增强。结论肝FNH、SNN和FFC的CEUS具有特异性表现,而IPL需与原发性肝细胞癌相鉴别。     

超声造影对甲状腺结节诊断价值的初步研究

目的初步研究探讨超声造影对甲状腺结节的诊断价值。方法35个甲状腺结节行超声造影检查,观察造影剂进入病灶至消退的全过程,并用QLAB软件进行时间-强度曲线分析。结果结节性甲状腺肿的超声造影表现以等增强、低增强为主,少数为高增强;腺瘤呈＂快进慢退高增强＂的造影表现;甲状腺癌以等增强及低增强为主,增强回声不均匀,消退早于周边甲状腺组织。结论超声造影能为甲状腺结节良恶性的鉴别诊断提供更多的微血管灌注信息,具有一定的诊断价值。     

超声在甲状腺乳头状癌术前分期中的应用价值

目的探讨超声在甲状腺乳头状癌术前分期中的应用价值。 方法收集2014年1至11月中国医学科学院肿瘤医院经术后病理学检查证实的甲状腺乳头状癌患者121例,共169个病灶。分析肿瘤大小、甲状腺被膜外侵犯范围及颈部淋巴结转移等超声表现,根据国际抗癌联盟（UICC）（第6版）甲状腺癌分期标准行术前分期,并与病理分期对照,评估超声在甲状腺乳头状癌术前分期中的应用价值。 结果超声评估甲状腺被膜侵犯的敏感度、特异度、阳性预测值和阴性预测值分别为89.6%（60/67）、72.2%（39/54）、80.0%（60/75）、84.8%（39/46）。术前超声诊断T₁～T₄正确率分别为75.0%（36/48）、100%（1/1）、81.9%（59/72）、0。超声诊断颈部淋巴结转移的敏感度、特异度、阳性预测值和阴性预测值分别为47.5%（29/61）、90.0%（54/60）、82.9%（29/35）、62.8%（54/86）。 结论超声在甲状腺乳头状癌术前分期方面具有较高的应用价值,且有助于判断肿瘤甲状腺外侵犯范围及颈侧部淋巴结转移。     

超声造影对甲状腺肿块诊断价值的初步探讨

目的初步探讨超声造影在甲状腺肿块诊断中的应用价值。方法26例29个甲状腺肿块术前常规二维及彩色多普勒超声检查后,行超声造影检查,观察造影剂开始显影、达峰及消退的全过程,并用ACQ软件进行时间-强度曲线分析。结果结节性甲状腺肿的超声造影表现大多以等增强、低增强为主,少数为高增强;腺瘤呈＂快进慢退高增强＂的造影表现,为富血供型;甲状腺癌大多以等增强及低增强为主,增强回声不均匀,早于周边甲状腺组织消退。结论超声造影对甲状腺肿块良恶性的鉴别提供了更多的信息,有一定的诊断作用。     

Contrast-enhanced ultrasonography for blood flow detection in hepatocellular carcinoma during lenvatinib therapy

Purpose

Blood flow reduction after initiation of lenvatinib therapy may not always indicate tumor necrosis. This study aimed to compare the blood flow detectability of contrast-enhanced ultrasonography (CEUS), contrast-enhanced computed tomography (CT), and contrast-enhanced magnetic resonance imaging (MRI) in hepatocellular carcinoma (HCC) during lenvatinib therapy.

Methods

A total of 12 cases underwent CEUS and contrast-enhanced CT/MRI within 2 weeks during lenvatinib therapy. Vascularity on CEUS and CT/MRI was compared.

Results

At the time of CEUS examination, the median period from the start of lenvatinib was 227?±?210 (31–570) days. CEUS showed hyperenhancement in eight cases (66.7%), hypoenhancement in two cases (16.7%), and no enhancement in one case (8.3%), while CT/MRI showed hyperenhancement in one case (8.3%), ring enhancement in three cases (25.0%), and hypoenhancement in eight cases (66.7%) (p?=?0.007). Transarterial chemoembolization (n?=?3), radiofrequency ablation (n?=?2), and stereotactic body radiation therapy (n?=?2) were performed after blood flow detection by CEUS.

Conclusions

The viability of the HCC should be confirmed using CEUS when contrast-enhanced CT/MRI reveals lesion hypoenhancement during lenvatinib therapy.

     

Imaging of peripheral cholangiocarcinoma with low-mechanical index contrast-enhanced sonography and SonoVue: initial experience.

OBJECTIVE: The purpose of this study was to investigate the imaging findings of peripheral cholangiocarcinoma with low-mechanical index (MI) contrast-enhanced sonography. METHODS: Eighteen nodules of peripheral cholangiocarcinoma proved by pathologic examination in 18 patients were evaluated with contrast-enhanced sonography. A low-MI real-time contrast-enhanced sonographic mode (ie, contrast pulse sequencing) and a sulfur hexafluoride-filled microbubble contrast agent (SonoVue [BR1]; Bracco SpA, Milan, Italy) were used. RESULTS: On contrast-enhanced sonographic images, all 18 nodules (100%) of peripheral cholangiocarcinoma showed inhomogeneous enhancement during the arterial phase, and the emergence of nodule enhancement was earlier in 3 nodules (16.7%), simultaneous in 13 (72.2%), and later in 2 (11.1%), respectively, when compared with the adjacent liver tissue. During the arterial phase, 8 nodules (44.4%) showed irregular peripheral rimlike hyperenhancement, 2 (11.1%) showed inhomogeneous hyperenhancement, and 8 (44.4%) showed inhomogeneous hypoenhancement. In portal and late phases, all 18 nodules (100%) showed hypoenhancement. When contrast-enhanced sonography was added for analysis, the confidence levels of the investigators were improved in 15 (83.3%) of 18 nodules, and 17 (94.4%) of 18 peripheral cholangiocarcinomas were correctly characterized. CONCLUSIONS: The imaging findings of peripheral cholangiocarcinoma had some characteristics on low-MI contrast-enhanced sonography. Knowledge of these characteristics might be beneficial for improving the diagnostic performance of sonography in evaluating this entity.     

The analysis of enhancement pattern of hepatic inflammatory pseudotumor on contrast-enhanced ultrasound

Objective

The aim of this study was to assess the role of contrast-enhanced ultrasound (CEUS) in the characterization of hepatic inflammatory pseudotumor (IPT).

Methods

We retrospectively reviewed 36 cases of histopathologically diagnosed IPT. Nodule enhancement appearances during the arterial, portal, and delayed phases were defined as hyperenhancement, isoenhancement, hypoenhancement, and non-enhancement compared with the surrounding liver parenchyma. Statistical analysis was performed by the one-way ANOVA and χ ² tests.

Results

Among total 36 cases, 7 nodules were absent of contrast enhancement during all three phrases on CEUS. Twenty-nine nodules appeared different forms of enhancement in arterial phase. Diffuse homogeneous hyperenhancement, diffuse heterogeneous hyperenhancement, peripheral rim-like enhancement, and diffuse iso-enhancement were found in 10, 12, 5, and 2 of the nodules, respectively. Twenty-five nodules showed hypoenhancement in portal and delayed phases. Four nodules showed contrast washed out synchronously with normal liver parenchyma. The median time to enhancement, median time to peak, and median time to wash out of the nodules were 17 s (range 11–28 s), 23 s (range 14–42 s), and 45 s (range 23–100 s), respectively. No statistical significant differences were found in the above parameters of nodule enhancement and proportion of enhancement patterns when dividing the nodules into subgroups by nodule size.

Conclusion

IPT displays a variety of enhancement patterns due to pathological changes in the course of disease progression. Some characteristics on CEUS may be helpful in the differential diagnosis of IPT.     

Characterization of focal liver lesions using contrast-enhanced sonography with a low mechanical index mode and a sulfur hexafluoride-filled microbubble contrast agent

PURPOSE: To characterize focal liver lesions (FLLs) using real-time contrast-enhancedsonography (CEUS) with a low mechanical index mode and a sulfur hexafluoride-filled microbubble contrast agent. METHODS: CEUS was performed in 190 patients with FLLs, including hepatocellular carcinoma (HCC) (n = 107), liver metastasis (n = 21), intrahepatic cholangiocarcinoma (ICC) (n = 7), liver hemangioma (n = 37), focal nodular hyperplasia (FNH) (n = 11), regenerative nodule (n = 6) and liver lipoma (n = 1). The cadence contrast pulse sequencing technique and the contrast agent SonoVue(R) were used for CEUS examination. The enhancement patterns during the arterial, portal, and late phases were evaluated. RESULTS: HCC showed hyperenhancement in 100 (93.5%) of 107 nodules during the arterial phase and hypoenhancement in 102 (95.3%) during the late phase. Liver metastases showed homogeneous enhancement in 8 of 21 (38.1%) nodules and a peripheral regular rim-like enhancement in 11 of 21 (52.4%) nodules during the arterial phase and marked hypoenhancement in 16 of 21 (76.2%) nodules during the late phase. ICC exhibited irregular rim-like enhancement in 4 of 7 (57.1%) nodules during the arterial phase and hypo-enhancement in 7 of 7 (100%) nodules during the late phase. Hemangioma showed peripheral nodular hyperenhancement, and progressive centripetal enhancement was seen in 35 of 37 (94.6%) lesions during the arterial phase. All 11 cases of FNH exhibited homogeneous hyperenhancement during the arterial phase and hyperenhancement (n = 1) or isoenhancement (n = 9) during the late phase. The sensitivity, specificity, and positive predictive value, respectively, were 88.8%, 89.2%, and 91.3% for HCC; 81%, 100%, and 100% for liver metastasis; 57.1%, 100%, and 100% for ICC; 94.6%, 100%, and 100% for liver hemangioma; and 90.9%, 97.8%, and 71.4% for FNH. CONCLUSIONS: Low-mechanical index CEUS permits real-time, complete assessment of vascularity in FLLs, which in turn facilitates their characterization.