Differentiation between dysplastic nodule and early-stage hepatocellular carcinoma: The utility of conventional MR imaging

AIM:To elucidate the variety of ways early-stage hepatocellular carcinoma(HCC)can appear on magnetic resonance(MR)imaging by analyzing T1-weighted,T2-weighted,and gadolinium-enhanced dynamic studies.METHODS:Seventy-three patients with well-differentiated HCC(wHCC)or dysplastic nodules were retrospectively identified from medical records,and new histological sections were prepared and reviewed.The tumor nodules were categorized into three groups:dysplastic nodule(DN),wHCC compatible with Edmondson-Steiner grade I HCC(w1-HCC),and wHCC compatible with Edmondson-Steiner gradeⅡHCC(w2-HCC).The signal intensity on pre-contrast MR imaging and the enhancing pattern for each tumor were recorded and compared between the three tumor groups.RESULTS:Among the 73 patients,14 were diagnosed as having DN,40 were diagnosed as having w1-HCC,and 19 were diagnosed as having w2-HCC.Hyperintensity measurements on T2-weighted axial images(T2WI)were statistically significant between DNs and wHCC(P=0.006)and between DN and w1-HCC(P=0.02).The other imaging features revealed no significant differences between DN and wHCC or between DN and w1-HCC.Hyperintensity on both T1W out-phase imaging(P=0.007)and arterial enhancement on dynamic study(P=0.005)showed statistically significant differences between w1-HCC and w2-HCC.The other imaging features revealed no significant differences between w1-HCC and w2-HCC.CONCLUSION:In the follow-up for a cirrhotic nodule,increased signal intensity on T2WI may be a sign of malignant transformation.Furthermore,a noted loss of hyperintensity on T1WI and the detection of arterial enhancement might indicate further progression of the histological grade.

Expression of heat shock proteins (HSP27, HSP60, HSP70, HSP90, GRP78, GRP94) in hepatitis B virus-related hepatocellular carcinomas and dysplastic nodules

AIM: Expression of heat shock proteins (HSPs) is frequently up-regulated in hepatocellular carcinoma (HCC), which evolves from dysplastic nodule (DN) and early HCC to advanced HCC. However, little is known about the differential expression of HSPs in multistep hepatocarcinogenesis. It was the purpose of this study to monitor the expression of HSPs in multistep hepatocarcinogenesis and to evaluate their prognostic significance in hepatitis B virus (HBV)related HCC.METHODS: Thirty-eight HCC and 19 DN samples were obtained from 52 hepatitis B surface antigen-positive Korean patients. Immunohistochemical and dot immunoblot analyses of HSP27, HSP60, HSP70, HSP90, glucoseregulated protein (GRP)78, and GRP94 were performed and their expression at different stages of HCC development was statistically analyzed.RESULTS: Expression of HSP27, HSP70, HSP90, GRP78, and GRP94 increased along with the stepwise progression of hepatocarcinogenesis. Strong correlation was found only in GRP78 (Spearman's r= 0.802). There was a positive correlation between the expressions of GRP78, GRP94, HSP90, or HSP70 and prognostic factors of HCC. Specifically, the expression of GRP78, GRP94, or HSP90 was associated significantly with vascular invasion and intrahepatic metastasis.CONCLUSION: The expressions of HSPs are commonly up-regulated in HBV-related HCCs and GRP78 might play an important role in the stepwise progression of HBVrelated hepatocarcinogenesis. GRP78, GRP94, and HSP90 may be important prognostic markers of HBV-related HCC, strongly suggesting vascular invasion and intrahepatic metastasis.

Multistep hepatocarcinogenesis from a dysplastic nodule to well-differentiated hepatocellular carcinoma in a patient with alcohol-related liver cirrhosis

We describe a rare case of the transformation of a dysplastic nodule into well-differentiated hepato- cellular carcinoma (HCC) in a 56-year-old man with alcoholrelated liver cirrhosis. Ultrasound (US) disclosed a 10 mm hypoechoic nodule and contrast enhanced US revealed a hypovascular nodule, both in segment seven. US-guided biopsy revealed a high-grade dysplastic nodule characterized by enhanced cellularity with a high N/C ratio, increased cytoplasmic eosinophilia, and slight cell atypia. One year later, the US pattern of the nodule changed from hypoechoic to hyperechoic without any change in size or hypovascularity. US-guided biopsy revealed well-differentiated HCC of the same features as shown in the first biopsy, but with additional pseudoglandular formation and moderate cell atypia. Moreover, immunohistochemical staining of cyclase- associated protein 2, a new molecular marker of well- differentiated HCC, turned positive. This is the first case of multistep hepatocarcinogenesis from a dysplastic nodule to well-differentiated HCC within one year in alcohol-related liver cirrhosis.

Classification tool for the systematic histological assessment of hepatocellular carcinoma, macroregenerative nodules, and dysplastic nodules in cirrhotic liver

AIM： To design a classification tool for the histological assessment of hepatocellular carcinoma （HCC）, dysplastic nodules （DN）, and macroregenerative nodules （MRN） in cirrhotic liver. METHODS： Two hundred and twelve hepatocellular nodules （106 HCC; 74 IRN, 32 DN） were assessed systematically, quantitatively, and semiquantitatively as appropriate for 10 histological features that have been described as helpful in distinguishing small HCC, DN, and MRN in cirrhotic livers. The data were analyzed by multiple correspondence analysis （MCA）. RESULTS： HCA distributed HCC, DN, and HRN as defined by traditional histological evaluation as well as the individual histological variables, in a ＂malignancy scale＂. Based on the MCA data representation, we created a classification tool, which categorizes an individual nodular lesion as MRN, DN, or HCC based on the balance of all histological features （i.e., vascular invasion, capsular invasion, tumor necrosis, tumor heterogeneity, reticulin loss, capillarization of sinusoids, trabecular thickness, nuclear atypia, and mitotic activity）. The classification tool classified most （83%） of a validation set of 47 nodules in the same way as the routine histological assessment. No discrepandes were present for DN and MRN between the routine histological assignment and the dassification tool. Of 25 HCC assigned by routine assessment in the validation set, 8 were assigned to the DN category by the classification tool. CONCLUSION： We have designed a classification tool for the histological assessment of HCC and its putative precursors in cirrhotic liver. Application of this toolsystematically records histological features of diagnostic importance in the evaluation of small HCC.

Contrast-enhanced ultrasound in the diagnosis of nodules in liver cirrhosis

Contrast-enhanced ultrasound(CEUS)using microbubble contrast agents are useful for the diagnosis of the nodules in liver cirrhosis.CEUS can be used as a problem-solving method for indeterminate nodules on computed tomography(CT)or magnetic resonance imaging(MRI)or as an initial diagnostic test for small newly detected liver nodules.CEUS has unique advantages over CT and MRI including no renal excretion of contrast,real-time imaging capability,and purely intravascular contrast.Hepatocellular carcinoma(HCC)is characterized by arterial-phase hypervascularity and later washout(negative enhancement).Benign nodules such as regenerative nodules or dysplastic nodules are usually isoechoic or slightly hypoechoic in the arterial phase and isoechoic in the late phase.However,there are occasional HCC lesions with atypical enhancement including hypovascular HCC and hypervascular HCC without washout.Cholangiocarcinomas are infrequently detected during HCC surveillance and mostly show rimlike or diffuse hypervascularity followed by rapid washout.Hemangiomas are often found at HCC surveillance and are easily diagnosed by CEUS.CEUS can be effectively used in the diagnostic work-up of small nodules detected at HCC surveillance.CEUS is also useful to differentiate malignant and benign venous thrombosis and to guide and monitor the local ablation therapy for HCC.

A Blood Hepatocellular Carcinoma Signature Recognizes Very Small Tumor Nodules with Metastatic Traits

Background and Aims:Hepatocellular carcinoma(HCC)cases with small nodules are commonly treated with radi-ofrequency ablation(RFA),but the recurrence rate remains high.This study aimed to establish a blood signature for identifying HCC with metastatic traits pre-RFA.Methods:Data from HCC patients treated between 2010 and 2017 were retrospectively collected.A blood signature for meta-static HCC was established based on blood levels of alpha-fetoprotein and des-γ-carboxy-prothrombin,cell-free DNA(cfDNA)mutations,and methylation changes in target genes in frozen-stored plasma samples that were collected before RFA performance.The HCC blood signature was validated in patients prospectively enrolled in2021.Results:Of 251 HCC patients in the retrospective study,33.9% experienced recurrence within 1 year post-RFA.The HCC blood signature identified from these patients included des-γ-carboxy-prothrombin≥40mAU/mL with cfDNA mutation score,where cfDNA mutations occurred in the genes of TP53,CTNNB1,and TERT promoter.This signature effectively predicted 1-year post-RFArecurrence of HCC with 92% specificity and 91% sensitivity in the retrospective dataset,and with 87% specificity and 76% sensitivity in the prospective dataset(n=32 patients).Among 14 cases in the prospective study with biopsy tissues available,positivity for the HCC blood signature was associated with a higher HCC tissue score and shorter distance between HCC cells and microvasculature.Conclusions:This study established an HCC blood signature in pre-RFA blood that potentially reflects HCC with metastatic traits and may be valuable for predicting the disease’s early recurrence post-RFA.

增强MRI联合IVIM-DWI诊断小肝细胞癌价值研究

目的探讨增强磁共振(MRI)联合体素内不相干运动磁共振扩散加权成像(IVIM-DWI)诊断小肝细胞癌(sHCC)的价值。方法2020年5月~2023年5月我院收治的肝脏局灶性病变患者73例,所有患者均接受增强MRI和IVIM-DWI检查,观察病灶增强强化信号特点,分析病灶IVIM-DWI定量参数,即伪扩散系数(D^(*))、真实扩散系数(D)和灌注分数(f)。采用细针穿刺或取术后组织行病理学检查。应用受试者特征工作曲线(ROC)下面积(AUC)评估增强MRI联合IVIM-DWI诊断sHCC的效能。结果经病理学检查,在73例肝脏局灶性病变患者中,诊断sHCC者49例(67.1%)和肝脏异型性增生结节(DN)者24例(32.9%);sHCC病灶T1WI低信号、T2WI高信号、动脉期强化和肝胆期低信号占比分别为61.2%、83.7%、59.2%和89.8%,均显著高于DN病灶的20.8%、33.3%、25.0%和29.2%(P<0.05);sHCC病灶D*和D分别为(50.9±11.6)×10^(-3) mm^(2)/s和(0.8±0.2)×10^(-3) mm^(2)/s,均显著小于DN病灶【分别为(78.4±15.8)×10^(-3) mm^(2)/s和(1.2±0.3)×10^(-3) mm^(2)/s,P<0.05】,而两组f比较,差异无统计学意义【分别为(45.6±8.7)%对(43.9±9.5)%,P>0.5】;ROC分析表明,应用T1WI信号、T2WI信号、动脉期强化、肝胆期信号、D*和D联合诊断sHCC的AUC为0.968,其灵敏度和特异度分别为100.0%和86.0%。结论应用增强MRI和IVIM-DWI联合诊断sHCC的效能较高,可为临床诊疗提供有益的依据,值得进一步深入研究。

MRI鉴别诊断肝硬化退变结节与小肝癌

目的 探讨高场强MRI对肝硬化退变结节和小肝癌诊断与鉴别诊断价值。方法 对经临床和病理证实18 例24个肝硬化退变结节(DN)和15例26个小肝细胞癌(sHCC)的磁共振影像资料作回顾性对比分析。结果 18例24个DN中,同、反相位T1WI上呈等信号者4个,呈稍高信号者20个,占DN的83%(20/24); 26个HCC结节中,同相位T1WI上呈稍高信号者6个,其中3个在反相位T1WI上呈低信号;同、反相位T1WI上均呈等低信号者19 个结节,占76%(19/25)。抑脂T2WI上DN组24个结节均为低信号;而小HCC组26 个结节中,呈稍高或不均匀等高信号者24 个,占92%(24/26), 2个在T2WI上为低信号。Gd DTPA动态增强扫描,14 例中15 个DN呈缓升速降型14 个,占93%;14 例中24个HCC呈速升速降型19个,占79%(19/24); HCC包膜强化率占增强病灶中的70%(17/24),而13个DN见不规则纤细网状纤维隔强化,占86%(13/15),仅1个DN呈假包膜样强化。结论 综合分析高场强MR不同序列及动态增强像特点,能够区别绝大多数大DN和HCC。

肝硬化结节及小肝癌患者3.0T MRI检查结果分析

目的评价3.0 T MRI检查在肝硬化再生性结节(RN)、异型增生性结节(DN)和小肝癌(SHCC)诊断和鉴别诊断中价值。方法回顾性分析经病理检查确诊的69例RN、DN及SHCC患者的3.0 T MRI平扫及容积采集技术(LAVA)三期动态增强扫描特点。结果 RN主要表现为T2WI低信号,动态增强方式呈"缓慢上升型";DN主要表现为T2WI高、低信号,信号较均匀结节的动态方式以"速升缓降型"为主,可有"结中结"(特征表现);SHCC主要表现为T1WI低信号、T2WI高信号,动态增强方式为"速升速降型"。结论肝硬化结节及小肝癌在3.0 T MRI上各有较为典型的表现,临床可据此进行诊断与鉴别诊断;对其他强化类型的肝脏病灶应结合肿瘤血管的扭曲增粗及包膜等表现排除SHCC。

肝内结节性病变MRI信号改变与血供的关系

【目的】以肝硬化基础上发生的再生性结节(RN)、增生性结节(DN)、小肝癌(SHCC)的MRI信号表现推断病灶的血供特点,分析病灶血供与信号变化的对应关系。【方法】对经病理证实的17个DN、16个RN和45个SHCC病灶进行回顾性分析,观察病灶的大小、信号强度、强化的方式和时间,推断病灶的血供特点,分析病灶血供与信号变化的关系。【结果】RN为T1WI高、T2WI低的信号,动态增强为缓慢上升型,提示动脉、门脉血供均少;DN在T1WI高、中、低信号均有,T2WI为等信号和稍高信号,动态增强为速升缓降型,提示动脉供血增多、门脉正常;SHCC以T1WI低、T2WI高信号为主,动态增强为速升速降型,提示动脉血供增多、门脉减少。由RN到SHCC,相应的T1WI和T2WI信号高低之间有统计学差异(P<0.05)。【结论】从RN到SHCC,动脉血供逐渐增多,门脉血供逐渐减少,T2WI信号由低转高,T1WI由高转低,血供与信号之间有一定的对应关系。

HBV相关肝硬化结节癌变的MR增强特征与GPC-3、CD34表达的对应性研究

目的探索乙型肝炎病毒(hepatitis B virus,HBV)相关肝硬化结节癌变磁共振(magnetic resonance,MR)动态增强特征与免疫组织化学标志物磷脂酰肌醇蛋白聚糖-3(glypican-3,GPC-3)及CD34表达量之间的对应关系。方法收集44个乙型肝炎(以下简称乙肝)肝硬化患者中经病理证实的47个肝硬化结节纳入本研究,术前均行MR扫描,用软件将动态增强扫描序列自动生成时间-信号曲线,术后常规病理及免疫组织化学染色,观察GPC-3和CD34表达。结果 1)在47个结节中,GPC-3在早期肝癌(early hepatocellular carcinoma,e HCC),高级不典型增生结节(high grade dysplastic nodule,HGDN),低级不典型增生结节(low grade dysplastic nodule,LGDN)各组中的阳性率分别为78.9%、26.1%、0%,CD34强阳性表达在e HCC、HGDN及LGDN中分别为78.9%、56.5%、0%,差异均有统计学意义(P<0.05)。2)e HCC、HGDN、LGDN的MR动态灌注时间-信号曲线特点分别倾向为陡升型、缓升型、平行型。GPC-3阳性的结节和阴性的结节两者之间时间信号曲线差异有统计学意义(P<0.05)。CD34强阳性、弱阳性、阴性的e HCC之间时间-信号曲线差异有统计学意义(P<0.05)。结论 1)MR时间-信号曲线特点对e HCC及HGDN的鉴别诊断有一定的价值。2)GPC-3表达阳性具有提示结节良恶性的诊断价值,同时MR时间-信号曲线表现为陡升型。3)CD34表达量与MR增强时间-信号曲线呈正相关。

HBV相关肝硬化结节演变的多模态MRI研究

目的:通过与病理结果进行对照分析,总结肝硬化再生结节多步演变的多模态MRI影像特征,探讨肝硬化再生结节的早期诊断及鉴别诊断价值。方法:搜集乙肝肝硬化患者50例(85个结节),回顾性分析其MRI平扫及增强扫描资料,对病理证实的多步演变结果与对应的MRI影像表现进行对照研究。结果:MRI检出82个结节,检出率为96.5%,T2WI和动态增强扫描是检测再生结节较敏感的序列,检出率分别为93.9%和96.3%,磁敏感成像(SWI)的检出率稍低(69.5%);再生结节(RN)与低级不典型增生结节(LGDN)(χ2=8.348,P=0.004)、高级不典型增生结节(HGDN)与肝细胞癌(HCC)(χ2=4.612,P=0.032)的MRI诊断符合率差异均有统计学意义。T1WI图像上LGDN的信噪比(SNR)值与RN、HGDN、HCC比较差异均有统计学意义(P值均<0.05);T2WI图像上HCC的SNR值与RN、LGDN、HGDN比较差异均有统计学意义(P值均<0.05)。结论:MRI是目前检测肝硬化结节最敏感的无创性检查方法,通过MRI与病理的对照分析,多模态序列从不同角度反映了肝硬化再生结节的影像学特征及演变规律,对肝硬化再生结节的诊断及鉴别诊断具有一定价值。

多层螺旋CT四期动态扫描对肝硬化小结节定性诊断的初步评价

目的评价多层螺旋CT(MSCT)四期动态扫描对肝硬化小结节的检出率,并对检出敏感性和定性准确性进行研究。方法经B超检查有直径小于3cm的肝硬化小结节者60例,行多层螺旋CT四期动态扫描,统计各期病灶的检出数,观察病灶强化方式,计算检出敏感性。采用美国GE公司的Lightspeed 4层螺旋扫描机行增强后四期扫描,第一期的延迟时间为25s,第二期为50s左右,第三期为90s,第四期180s。结果60例共发现72个,其中56个小肝癌,再生结节6个,退变结节10个。平扫发现36个病灶(63%,36/56);第一期、第二期、第三期及第四期病灶检出敏感性分别为66%、58%、50%、92%。结论肝硬变小结节增强扫描表现形式复杂,螺旋CT四期扫描可以充分显示肝硬化小结节各期的增强表现,充分反映小结节血供的特点,提高了病灶的检出率和定性诊断的准确率、

肝硬化结节与小肝癌的临床及MRI诊断

目的:探讨MRI对肝硬化结节(再生结节、退变结节)与小肝癌的诊断及鉴别诊断价值。方法:收集120例临床诊断为肝硬化的MRI资料,其中32例行Gd-DTPA动态增强扫描。结果:全部病例均见再生结节,其中合并退变结节14例、原发小肝细胞癌18例,再生结节为肝内弥漫的小于1.0cm结节状病灶,T1WI呈等或略高信号、T2WI呈略低信号影;退变结节为直径1.0cm～3.5cm结节状病灶,T1WI呈等或略高信号、T2WI呈等信号影;小肝细胞癌为直径小于3.0cm结节状病灶,T1WI呈略低信号、T2WI呈略高信号影。Gd-DTPA动态增强扫描见小肝癌于肝动脉期明显强化,门静脉期强化消退。结论:根据结节大小、信号改变MRI可区分大部分再生结节、退变结节及小肝细胞癌。Gd-DTPA动态增强扫描有助于鉴别困难的退变结节及小肝细胞癌。

MRI对肝硬化伴肝癌和非典型性结节诊断的敏感性观察

目的探讨MRI对肝硬化伴肝癌和非典型性结节的敏感性.方法74例肝硬化患者肝移植前90d内行MRI检查,并同肝移植术后病理切片作对照.所有患者检查前均不知其有无肝癌,FLASH/T1WI、TSE/T2WI序列、动态3期增强扫描被获得.结果病理发现13例患者共21处肝脏有恶性病变,MRI发现其中12/21个恶性病变,敏感性为57.1%,其中发现87.5%（7/8）≥2cm的病变,44.4%（4/9）1～2cm的病变,25.0%（1/4）＜1 cm的病变;对≥2cm和＜2cm组的恶性病变的差异有统计学意义（P＜0.05）.病理检查发现14例患者（14/74）共47个DN,MRI诊断9/47个DN病变,敏感性仅19.1%.结论MRI对肝硬化伴＞2cm的肝癌敏感性较好,但对＜2cm的肝癌及非典型性结节敏感性较差.

HSP70、GPC3、GS和AKR1B10在肝脏高度异型增生结节免疫组化诊断中的应用

目的探讨免疫组化标志物热休克蛋白70(heat shock protein 70,HSP70)、磷脂酰肌醇蛋白聚糖3(glypican 3,GPC3)、谷氨酰胺酶(glutamine synthetase,GS)和正醛酮还原酶家族中单分子醛糖还原酶(aldo-ketoreductase family 1 member B10,AKR1B10)在肝脏高度异型增生结节(high-grade dysplastic nodule,HGDN)和高分化小肝细胞癌(well-differentiated small hepatocellular carcinoma,WD-SHCC)中的表达特点及鉴别诊断价值。方法对16例单结节型HGDN和32例WD-SHCC进行HSP70、GPC3、GS和AKR1B10免疫组化染色。结果 4项标志物在HGDN与WD-SHCC组织中均可表达,单项标志物中,HSP70在HGDN与WD-SHCC中阳性率最高(31.25%,81.25%,P<0.001);GPC3在HGDN与WD-SHCC中阳性率最低(12.50%,25.00%,P<0.460)。HSP70+GPC3+GS及HSP70+AKR1B10+GS诊断组合均在3项标志物中至少2项阳性时,获取最佳诊断效果,此时诊断敏感性和准确率分别为62.50%、81.25%和70.83%、83.33%,特异性均为87.50%。结论HSP70、GPC3和GS经典免疫组化诊断谱对HGDN和WD-SHCC组织具有一定的鉴别能力。然而,GPC3在WD-SHCC中阳性率较低,表达水平与HGDN无明显差异,制约该谱的整体诊断效果。AKR1B10替代GPC3后,在维持较高特异性一致的同时,可明显提高诊断敏感性和准确率。

PWI在肝硬化增生性结节诊断中的应用

目的 :探讨PWI在肝硬化增生性结节(dysplastic nodule,DN)诊断中的应用。方法 :回顾性分析经病理证实的40例DN患者的PWI资料,获得每个DN的时间-信号强度曲线(time intensity curve,TIC)和峰值时间(time to peak,TTP),计算肝脏动脉灌注指数(hepatic perfusion index,HPI)。结果:28例28个DN为低级别DN(low grade DN,LGDN),TIC主要呈缓升缓降型20个,TTP为(41.56±1.67)s,HPI为0.27±0.04;12例14个DN为高级别DN(high grade DN,HGDN),TIC主要呈速升缓降型11个,TTP为(39.81±2.36)s,HPI为0.45±0.06。结论:PWI能客观地反映DN的血流情况,有助于DN的诊断和鉴别诊断。

肝脏影像报告和数据系统中恶性辅助征象对小肝细胞癌的分类及诊断效能的影响

目的探究基于钆塞酸二钠增强MRI(Gd-EOB-MRI)2018版肝脏影像报告和数据系统(LI-RADS v2018)恶性辅助征象对<20 mm的小肝细胞癌(HCC)分类及诊断效能的影响。方法回顾性收集未经治疗且经病理证实为HCC、再生结节(RN)、高级别异型增生结节(HGDN)、低级别DN(LGDN)109例病人,共纳入<20 mm病灶130个。采用卡方检验或Fisher确切概率检验比较各组病灶的主要和辅助征象并筛选HCC特异性辅助征象。按以下方法将病灶分类:(1)主要征象分类法;(2)主要+辅助征象分类法,即先依据主要征象分类,再由辅助征象调整;(3)添加主要征象分类法,即将HCC特异性辅助征象添加为主要征象,再按方法2分类。分别计算3种分类方法中LR-5和LR-(4+5)对HCC的诊断效能,并采用McNemar’s检验比较其差异。结果移行期(TP)及肝胆期(HBP)低信号为HCC特异性辅助征象(均P<0.05),被添加为主要征象。主要征象分类和主要+辅助征象分类下LR-5对HCC的诊断敏感度、特异度、准确度相同(67.0%、75.8%、74.6%),与添加主要征象分类法(74.2%、78.8%、70.0%)比较,仅诊断敏感度降低(P<0.05),而特异度及准确度差异无统计学意义(P>0.05)。主要+辅助征象分类和添加主要征象分类下LR-(4+5)对HCC的诊断敏感度、特异度、准确度相同(88.7%、75.4%、36.4%),与仅依据主要征象分类法(83.5%、78.5%、63.6%)比较,其敏感度及准确度差异均无统计学意义(P>0.05),但特异度降低(P<0.05)。结论经辅助征象调整后的分类不能改变LR-5对小HCC的诊断效能,却降低了LR-(4+5)诊断HCC的特异度。将TP/HBP低信号作为新的HCC主要征象重新分类,可以提高LR-5诊断HCC的敏感度,但特异度和准确度不降低。

磁共振灌注成像对肝硬化增生性结节与小肝癌的鉴别诊断

目的探讨磁共振灌注成像对肝硬化增生性结节和小肝癌的鉴别诊断价值。方法分析经临床和病理证实11例11个肝硬化增生性结节(DN)和18例18个小肝细胞癌(SHCC)的磁共振灌注成像资料,获取每个病灶的时间-信号强度曲线(TIC),记录病灶的峰值时间(TTP),计算肝脏动脉灌注指数(HPI)并进行比较。结果 DN的TIC呈缓升缓降型;SHCC的TIC呈速升速降型,DN和SHCC的TTP分别为(39.56±1.67)s、(25.21±1.38)s,HPI分别为0.26±0.04、0.75±0.02,DN和SHCC TTP、HPI有统计学差异(P<0.05)。结论 MR灌注成像技术可以提供比传统图像更多有用的肿瘤血供信息,有助于鉴别DN和SHCC。

平扫和动态增强MR诊断肝脏增生性结节

目的总结增生性结节(DN)在MRI平扫及动态增强扫描中的特征。资料与方法回顾性分析行Gd-DTPA动态增强MR检查并经手术病理证实的DN共11例16个病灶,观察病灶的大小、信号强度、强化方式和时间,测量各序列病灶及周围肝组织的信号强度和背景噪声标准差,计算信噪比及其差值。绘制病灶和周围肝组织的时间-信号强度曲线。结果16个病灶中有4个表现为"结中结",中央结节为T1WI低、T2WI等或高信号,动态增强为速升速降或速升缓降型,周围为T1WI高、T2WI等或高信号,动态增强为缓慢上升型;余12个病灶在T1WI上高、等和低信号均有,在T2WI上为等信号和稍高信号,动态增强过程中动脉期强化较明显,门静脉期以等信号为主,延迟期为等及稍高信号,未见呈低信号者。时间-信号强度曲线显示病灶为速升缓降型。结论"结中结"征象和动态增强早期强化、后期与周围肝组织类似信号的表现是DN的MRI特征。