钆塞酸二钠增强MRI对不典型肝细胞癌和肝内胆管细胞癌的鉴别诊断价值

目的 探讨钆塞酸二钠（Gd-EOB-DTPA） 增强 MRI对最大径≤3 cm的不典型肝细胞癌（HCC）及肝内胆管细胞癌（ICC）的鉴别诊断价值。 方法 回顾性纳入经病理证实的最大径≤3 cm的不典型HCC 26例[男17例,女9例,平均年龄（56.9±11.3）岁;HCC组]及ICC 21例[男16例,女5例,平均年龄（58.2±11.6）岁;ICC组]的临床及影像资料。评估2种肿瘤平扫及Gd-EOB-DTPA动态增强MRI上影像特征,包括肿瘤最大径、病灶边缘、病灶包膜、伴远端胆管扩张情况、病灶信号是否均匀、瘤体ADC值、动脉期强化特征、瘤周血流灌注是否异常、动态强化方式及肝胆期信号特征。采用t检验及χ ²检验分析2组的临床特征和常规平扫序列、增强MRI表现的差异,采用多因素Logistic回归分析鉴别两者的预测因素。2名影像医师对2种肿瘤的平扫及增强影像诊断结果的一致性分析采用kappa检验。 结果 HCC组病人相比ICC组多有肝炎及肝硬化病史,血清肿瘤标志物甲胎蛋白（AFP）高于ICC组,而ICC组的糖类抗原199（CA-199）水平更高;常规平扫序列MRI上HCC组病灶常有包膜,而ICC组常伴远端胆管扩张且ADC值更高;增强后ICC组更多表现为动脉期边缘强化、中央逐渐强化,更易出现肝胆期靶征改变（均P<0.05）。多因素Logistic回归分析显示增强动脉期边缘强化及肝胆期靶征为鉴别诊断HCC和ICC的重要预测征象。2名影像医师诊断一致性良好（κ=0.837,P<0.001)。 结论 Gd-EOB-DTPA 增强MRI肝胆期靶征和动脉期边缘强化对最大径≤3 cm的不典型HCC及ICC有重要鉴别诊断价值,可为治疗方案提供参考。     

乙型肝炎病毒所致慢性肝病病人肝脏铁沉积和脂肪变性的MRI定量研究

目的 根据多回波Dixon技术定量测得的R₂*值和质子密度脂肪分数（PDFF）评价乙型肝炎病毒（HBV）所致慢性肝病病人的肝脏铁含量和脂肪含量,探讨定量测量与病情进展的关系。方法 回顾性分析97例HBV所致慢性肝病病人,所有病人均行钆塞酸二钠（Gd-EOB-DTPA）增强MRI检查。根据病情进展状态将病人分为3组,慢性乙型肝炎（CHB）组21例,乙肝肝硬化（LC）组44例,LC合并肝细胞癌（HCC）组32例。另外纳入正常对照（NC）组20例。全部研究对象均进行了MRI多回波Dixon序列扫描,测量其肝实质R₂*值和PDFF;测量HCC病人病灶处的R₂*值和PDFF,获取所有LC病人的肝功能Child-Pugh评分。采用Kruskal-Wallis检验比较组间R₂*值和PDFF差异;采用配对t检验比较HCC组病灶与邻近正常肝组织的R₂*和PDFF。采用Spearman相关分析所有受试者R₂*值与PDFF,及LC病人Child-Pugh评分与其R₂*值、PDFF之间的相关性。结果 ①LC组、HCC组R₂*均高于NC组（均P<0.05）,HCC组R₂*高于CHB组（P<0.05）;HCC组PDFF高于NC组（P<0.05）。其余2组间R₂*和PDFF的差异均无统计学意义（均P>0.05）。②HCC病人病灶处的R₂*低于邻近正常肝组织（P<0.05）,而两者PDFF差异无统计学意义（P>0.05）。③所有受试者R₂*与PDFF呈正相关（r=0.558,P<0.05）,LC病人肝脏R₂*与Child-Pugh评分呈正相关（r=0.336,P<0.05）,PDFF与Child-Pugh评分无相关性（r=0.102,P>0.05）。结论 HBV所致慢性肝病病人可出现肝脏铁沉积和脂肪变性;随着病情的进展,肝脏铁含量和脂肪含量呈升高趋势;癌变病灶表现为肝脏富铁背景下的乏铁灶。     

扩散峰度成像对上皮性卵巢癌分型的鉴别诊断

目的 探讨扩散峰度成像（DKI）对Ⅰ型与Ⅱ型上皮性卵巢癌（EOC）的鉴别诊断价值。 方法 回顾性收集经手术病理证实的45例EOC病人的临床、病理及影像资料,平均年龄（50±13）岁。根据术后病理结果对EOC病人进行分组,分为Ⅰ型组（24例）和Ⅱ型组（21例）。所有病人均于术前行盆腔DKI检查,由2名放射科医师在DKI各参数伪彩图上分别测量平均扩散峰度（MK）、平行扩散峰度（Ka）、垂直扩散峰度（Kr）、平均扩散系数（MD）、平行扩散系数（Da）、垂直扩散系数（Dr）、各向异性分数（FA）、峰度各向异性分数（FAk）。采用Fisher确切概率检验、独立样本t检验或Mann-Whitney U检验比较2组间临床、病理及影像资料的差异,对差异有统计学意义的参数绘制受试者操作特征（ROC）曲线,分析其鉴别诊断效能。 结果 病理表现上,Ⅰ型中交界性肿瘤占比最高（50.0%）,Ⅱ型中浆液性癌占比最高（61.9%）;Ⅰ型中高分化癌占50%,Ⅱ型多表现为中低分化癌 （76.2%）,Ⅰ型EOC的分化程度高于Ⅱ型;Ⅰ型多数处于Ⅰ期（79.2%）,Ⅱ型多处于Ⅲ期(57.1%)（均P<0.05）。MRI影像上, Ⅰ型病灶多表现为囊性(41.7%)或囊实性（33.3%）,Ⅱ型多表现为实性（52.3%）;Ⅱ型（66.7%）腹水发生率高于Ⅰ型（29.2%）（均P<0.05）。Ⅰ型的MK、Ka和Kr值低于Ⅱ型,MD、Da和Dr值高于Ⅱ型（均P<0.05）。ROC曲线分析显示,MK阈值为0.504时,鉴别2组诊断的曲线下面积（AUC,0.817）最大,诊断敏感度（95.2%）、阴性预测值（92.9%）、准确度（78.9%）也最高,Da阈值为2.190时鉴别诊断的AUC（0.770）最小,而特异度（76.2%）、阳性预测值（75.9%）最高。 结论 DKI序列的定量参数MK、Ka、Kr、MD、Da及Dr均有助于鉴别Ⅰ型与Ⅱ型EOC,其中MK值鉴别诊断效能更大。     

Gd-EOB-DTPA增强MRI诊断肝局灶性结节增生的价值

肝局灶性结节增生(focal nodular hyperplasia,FNH)为肝脏较为少见的良性肿瘤样病变,组织学上由肝细胞、胆管、Kupffer细胞和中间的纤维间隔构成.出血、坏死、恶变等并发症极其罕见,临床上一般不做特殊处理,所以正确的影像诊断很重要.本文通过分析FNH在平扫及钆塞酸二钠(gadolinium ethoxybenzyl diethylene triamine pentaacetic acid,Gd-EOB-DTPA,商品名:普美显)增强MRI动态三期及肝胆期的表现特征,探讨Gd-EOB-DTPA增强MRI对FNH的诊断价值.     

IVIM双指数、拉伸指数模型对子宫内膜癌分型的价值

目的 探讨体素内不相干运动（IVIM）双指数、拉伸指数模型各参数在Ⅰ型与Ⅱ型子宫内膜癌（EC）中的鉴别诊断价值。 方法 回顾性分析51例经手术病理证实的Ⅰ型（31例）与Ⅱ型（20例）EC病人的IVIM成像资料。由2名医师在IVIM各参数伪彩图上分别测量慢速表观扩散系数（ADC-slow）、快速表观扩散系数（ADC-fast）、灌注分数（f）、扩散分布指数（DDC）和扩散异质性指数（α）。采用组内相关系数（ICC）评价2名医师测量参数的一致性。采用Fisher确切概率法比较Ⅰ型与Ⅱ型EC的病理类型及分级分期。绘制受试者操作特征（ROC）曲线,分析2组间有统计学差异的参数及其诊断效能。 结果 2名医师所测数据的一致性较好（均ICC≥0.75）。Ⅰ型组的ADC-slow、DDC值均高于Ⅱ型组,ADC-fast值低于Ⅱ型组（均P<0.05）。ADC-slow值为0.500×10^-3 mm²/s时,鉴别Ⅰ型和Ⅱ型EC的AUC为0.926,敏感度、特异度、准确度分别为80.0%、90.3%、86.3%。 结论 双指数模型的参数ADC-slow、ADC-fast值和拉伸指数模型的参数DDC值均有助于鉴别Ⅰ型与Ⅱ型EC,其中ADC-slow值鉴别诊断效能更大。     

基于CT图像的纹理分析鉴别肝脏实性局灶性病变

目的 CT是鉴别肝脏实性局灶性病灶的常用检查方法,但其对不典型病灶的鉴别诊断仍有较大的经验依赖性,而纹理分析可以提供客观、定量的图像描述特征。本研究旨在探讨基于CT图像的纹理分析在肝脏实性局灶性病变鉴别诊断中的价值。资料与方法回顾性分析258例经病理证实或临床确诊的肝脏局灶性病变患者的CT图像,其中肝脏局灶性结节增生(FNH)34例,血管瘤(HEM)60例,肝细胞肝癌(HCC)60例,肝内胆管细胞癌(ICC)44例,转移瘤(MET)60例。所有患者均行腹部CT平扫与三期增强扫描。以Ma Zda软件生成CT图像的纹理特征并进行特征筛选,进行各组病灶的判别。结果 258例患者中,基于增强CT图像的纹理分析对于肝脏实性局灶性病变的鉴别诊断错判率(4.26%~37.80%)低于基于平扫图像的纹理分析(9.57%~39.02%)。对于良恶性病变的鉴别,门静脉期图像纹理分析错判率最低(13.57%);对于FNH与HEM的鉴别,动脉期及门静脉期图像纹理分析效果相当(错判率为4.26%);对于恶性肿瘤间的鉴别纹理分析错判率相对较高,若于恶性肿瘤间两两鉴别则错判率可降低(错判率最低为HCC与MET,约11.67%)。结论基于CT图像的纹理分析可以作为肝脏实性局灶性病灶鉴别诊断的辅助手段,尤其是FNH与HEM、良性病灶与恶性病灶、恶性病灶间的两两鉴别;其中基于三期增强扫描的纹理分析较基于平扫图像者效果更优。     

增强CT和MRI轮辐征在诊断肝脏局灶性结节增生中的价值

目的 分析增强CT和MRI轮辐征在鉴别诊断肝脏局灶性结节增生(FNH)和其他肝脏局灶性病变中的价值.方法 回顾性分析经病理证实的210例肝脏局灶性病变患者的增强CT及MRI图像,其中FNH 37例(40个病灶),其他肝脏局灶性病变173例(219个病灶).采用x2检验比较不同检查方式、增强期相FNH轮辐征的检出率,计算...     

大脑中动脉不同部位急性脑梗死的DKI表现特点

目的 比较DKI各峰度参数与扩散参数早期诊断急性脑梗死的能力,评估大脑中动脉供血区不同部位急性脑梗死后DKI峰度参数的变化特点,探究早期诊断不同部位脑梗死的优势参数图。 方法 回顾性收集单侧大脑中动脉供血区的急性脑梗死病人62例（共84个病灶）,男37例,女25例,年龄43~71岁,平均（57.26±6.27）岁。行DKI扫描并获得轴向扩散率（AD）、平均扩散率（MD）、径向扩散率（RD）、轴向扩散峰度（AK）、平均扩散峰度（MK）、径向扩散峰度（RK）图。按梗死部位将所有病灶分为3组,包括皮质（28个）、皮质下白质（25个）和基底节区（31个）组。采用配对t检验比较各参数值患侧与健侧的差异,采用秩和检验比较各峰度参数变化率（Δ参数值%）的差异,采用单因素方差分析比较3组间各峰度参数健侧绝对值的差异。 结果 与健侧对照区相比,所有梗死灶的扩散参数（AD、MD、RD）值均减低,而峰度参数（AK、MK、RK）值均增高（均P<0.05）。其中,扩散参数的变化率均小于其对应峰度参数的（均P<0.05）。健侧对照区中,皮质下白质区和基底节区的MK、RK值均高于皮质区,而基底节区的RK值也高于皮质下白质区（均P<0.05）。皮质、皮质下白质、基底节区病灶的ΔAK%依次增大（P<0.05）。皮质组的ΔAK%、ΔMK%、ΔRK%的差异无统计学意义（P>0.05）;皮质下白质组的ΔAK%与ΔMK%均大于ΔRK%（均P<0.05）;基底节区组的ΔAK%、ΔMK%、ΔRK%数值呈降序分布（均P<0.05）。 结论 DKI峰度参数较扩散参数更易检出梗死病灶。缺血状态下,皮质下白质及基底节区的组织微结构改变较皮质更为复杂,且AK、MK较RK更有评估不同部位缺血损伤的潜力。对位于皮质、皮质下白质的脑梗死评估,MK图具有优势,而对基底节区的脑梗死早期评估,AK图更具优势。     

Gd-EOB-DTPA在肝脏局部结节性病变诊断中的应用

目的 研究肝细胞特异性对比剂Gd-EOB-DTPA在肝脏结节性病变定性诊断中的应用价值.方法 收集经CT或MR(Gd-DTPA)增强检查证实肝内有结节性病变的患者30例,再进行肝细胞特异性对比剂Gd-EOB-DTPA MR增强扫描,采集T1WI、T2WI、DWI、LAVA动态增强扫描,在注射对比剂后15～20 min采集肝胆特异摄取期图像.结果 30例入组患者,共发现36个病灶.其中中低分化肝细胞癌14个,高分化肝细胞癌8个,再生结节或不良性再生结节9个,局灶性再生结节5个.注射肝细胞特异性对比剂Gd-EOB-DTPA后,病灶在动静脉期强化方式与非特异性钆基对比剂Gd-DTPA相同;在对比剂Gd-EOB-DTPA被肝细胞摄取的特异期内观察,不同分化程度的肝细胞癌均表现为境界清晰的低信号,而不同阶段的肝硬化结节信号强度出现分化,肝局灶性结节均表现为等或稍高信号.结论 Gd-EOB-DTPA在肝脏结节性病变的定性诊断中有重要价值.     

LI-RADS辅助征象替代阈值增长对HCC的诊断效能

目的 探讨2018版肝脏影像报告和数据系统（LI-RADS v2018）中肝细胞癌（HCC）的特异性辅助征象替代主要征象中的阈值增长后,其中的LR-5对HCC的诊断效能。方法 回顾性收集未经治疗并行钆塞酸二钠增强MRI（Gd-EOB-MRI）且经病理证实的HCC和其他肝内恶性肿瘤（OM）病人262例共262个病灶。由2名放射科医师依据LI-RADS v2018对病灶进行分析,采用t检验比较HCC和OM病灶中伴和不伴阈值增长的病灶大小;分析HCC和OM病灶间主要和辅助影像征象的差异,并确定HCC特异性辅助征象。分别计算标准LI-RADS v2018以及HCC特异性辅助征象替代阈值增长后LR-5对HCC的诊断效能,并采用McNemar检验比较其差异。结果 262个病灶中,HCC 187个（71.4%）,OM 75个（28.6%）。共47个HCC和29个OM病灶用于阈值增长评价,其中22个HCC和14个OM病灶出现阈值增长。HCC和OM病灶中,伴有阈值增长的病灶直径均小于不伴阈值增长者（均P<0.05）。主要征象中,OM较HCC更常见阈值增长;辅助征象中,HCC较OM更常见结中结和病灶内含脂（均P<0.05）。以结中结和病灶内含脂作为特异性辅助征象替代阈值增长,诊断HCC的敏感度、特异度、准确度分别为75.4%、88.6%、81.0%和74.9%、89.3%、81.0%,诊断效能与标准LI-RADS v2018（74.3%、88.6%、80.4%）的差异没有统计学意义（均P>0.05）。结论 当阈值增长被HCC特异性辅助征象替代后,并未影响LI-RADS v2018诊断HCC的效能,即阈值增长可以被结中结和病灶内含脂替代。     

超顺磁性氧化铁在肝脏局灶性病变中的定性研究

目的 探讨超顺磁性氧化铁（SPIO）增强MRI在肝脏局灶性病变的定性能力。材料与方法 43例怀疑肝占位者经常规MRI和Gd-DTPA增强后1－7后,行SPIO增强检查。其中31例经手术病理证实,12例经随访、实验室生化检查及临床资料证实。分析平扫MRI及SPIO增强后病灶的信号变化,并与Gd-DTPA动态增强结果相对照。结果 43例共12种病变、单发病灶21例,多病灶22例。包括原发性肝细胞肝癌22例,血管瘤5例,囊肿4例,转移性肝癌5例,肝硬化结节4例,局灶性结节增生（FNH）5例,其他病变6例。22例多发病灶中有8例合并1或2种病变。SPIO增强后,肝细胞肝癌T1WI为等或略高信号,T2WI为较高信号;血管瘤T1WI为较高信号,T2WI信号同平扫为高信号;囊肿T1WI、T2WI信号无改变;肝硬化结节T2WI为等信号同正常肝实质;FNH T2WI信号明显下降。其余病变的诊断SPIO增强不具有特征性,须与Gd-DTPA动态增强相结合。结论 SPIO具有一定的定性能力Gd-DTPA增强相结合,可帮助提高肝局灶性病变诊断和鉴别诊断的准确性。     

Effect of superparamagnetic iron oxide-enhanced MRI of the liver with hepatocellular carcinoma and hyperplastic nodule

PURPOSE: To evaluate the possibility of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) of the liver in predicting the histologic grade of hepatocellular carcinoma (HCC) and differentiating HCC from benign hyperplastic nodule (HPN). MATERIALS AND METHODS: Thirty patients with 31 histologically proved HCC and HPN underwent MRI (1.5 Tesla). HCCs were graded into well-differentiated HCC (HCCw; n = 10) and moderately to poorly differentiated HCC (HCCmp; n = 15). HPN was categorized into dysplastic nodule (DN; n = 1) and focal nodular hyperplasia (FNH; n = 6). T2-weighted fast spin echo images were obtained before and after administration of SPIO. Signal-to-noise ratios (SNR) of the lesion and surrounding liver parenchyma and contrast-to-noise ratios (CNR) were calculated pre- and postcontrast study. Relative enhancement ratios (RER), also known as signal intensity reduction ratios of the lesions, were also calculated. RESULTS: HCCw, HCCmp, DN, and FNH decreased in SNR after injection of SPIO. RER of HCCw was 19.5 +/- 13.3%, that of HCCmp was 6.8 +/- 5.8%, DN was 44.0%, and FNH was 42.9 +/- 4.8%. Significant statistical differences were seen between HCCw and HCCmp and HCC and HPN in RER. HCCw, HCCmp, and DN increased in CNR, and FNH decreased in CNR, but no lesion showed a statistically significant difference in CNR. CONCLUSION: SPIO-enhanced MR images may help to predict the histologic grade of HCC and distinguish HCC from HPN.     

Focal nodular hyperplasia-like nodules in alcoholic liver cirrhosis: radiologic-pathologic correlation

OBJECTIVE: The purpose of this study was to describe our experience with three patients who had pathologically proven focal nodular hyperplasia (FNH)-like nodules that radiologically mimicked hepatocellular carcinoma (HCC). CONCLUSION: FNH-like nodules may radiologically mimic HCC, appearing as hypervascular masses on contrast-enhanced CT images and as high-signal-intensity masses on superparamagnetic iron oxide-enhanced MR images. Pathologically, there is the presence of a high number of unpaired arteries and sinusoidal capillarization, which may mimic HCC. Thus, it is important to differentiate FNH-like nodules radiologically, pathologically, and clinically from HCC.     

Incidence for progression of hypervascular HCC in hypovascular hepatic nodules showing hyperintensity on gadoxetic acid-enhanced hepatobiliary phase in patients with chronic liver diseases

Purpose

The purpose of this study was to elucidate the incidence and risk factors for the progression of hyperintense nodules, observed in the hepatobiliary phase of gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid-enhanced magnetic resonance imaging (Gd-EOB-DTPA-enhanced MRI), to hypervascular hepatocellular carcinoma (HCC).

Materials and methods

Hypovascular nodules (n = 157) showing hyperintensity in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were examined in 41 patients. All patients underwent computed tomography (CT) during hepatic arteriography and CT during arterial portography within one month of Gd-EOB-DTPA-enhanced MRI. The incidence of progression to hypervascular or classical HCC was calculated using the Kaplan–Meier method.

Results

Tumor size was determined by univariate and multivariate analysis to be an important risk factor of hypervascularization (p = 0.041, odds ratio 1.135). The cumulative incidences of hypervascularization in hypovascular nodules showing hyperintensity on the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI were 2.4, 4.5, and 6.2 % at 12, 24, and 36 months, respectively. The incidence of hypervascularization was significantly increased in nodules >10 mm in diameter (p = 0.00035).

Conclusion

In patients with chronic liver disease, hypovascular nodules presenting as hyperintense in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI and >10 mm in diameter have malignant potential for progression to hypervascular HCC and require careful management.     

Ring-like enhancement of focal nodular hyperplasia with hepatobiliary-phase Gd-EOB-DTPA-enhanced magnetic resonance imaging: radiological-pathological correlation

We report a case of focal nodular hyperplasia in a patient for whom gadolinium-ethoxybenzyl-diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) and histological analysis results were available. Dynamic contrast-enhanced computed tomography showed a well-defined hypervascular lesion 14 mm in diameter with no visible central scars. Gd-EOB-DTPA-enhanced MRI demonstrated strong peripheral enhancement of the lesion during the hepatobiliary phase, resulting in ring-like enhancement. The pathology examination revealed that the lesion was focal nodular hyperplasia (FNH). Immunohistochemistry showed positive expression of OATP8 in the hepatocytes in the peripheral areas of the lesion, whereas expression of OATP8 was lacking in hepatocytes surrounding the central radiating scar. Ring-like enhancement during the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI may be an important clue for the diagnosis of small FNH.     

Hepatocellular carcinoma in association with hepatic focal nodular hyperplasia

Purpose: To report the association between hepatocellular carcinoma (HCC) and hepatic focal nodular hyperplasia (FNH) and the possible impact on clinical decision-making with regard to resective approaches in patients with FNH.

Material and Methods: We retrospectively analyzed the findings in 77 adult patients who underwent liver resections for FNH between October 1989 and September 2001 at our center. HCC within the confines of FNH was found in two patients. We demonstrate the magnetic resonance imaging (MRI) and macroscopic and microscopic findings.

Results: Presurgical MRI demonstrated heterogeneous signal characteristics of moderately hyperintense FNH on T2-weighted images and, after IV administration of super-paramagnetic iron oxide particles, HCC in FNH was barely delineable. Both patients underwent successful right hemihepatectomy to remove the suspicious FNH with diameters of 12 and 14 cm; intralesional HCC diameters were 3 and 5 cm, respectively. Patients could be rapidly dismissed. However, one patient died after recurrence of HCC 1.5 years after surgery, whereas the other patient continues tumor-free 4 years after surgery. Alpha-feto-protein was normal in both patients.

Conclusion: In FNH with rapid growth tendency and heterogenic MR appearance, surgical removal should be considered to overcome the risk of inadequate therapy in the very rare group of patients with HCC in association with FNH.     

MRI诊断含脂质肝脏肿瘤的价值

目的:评估MRI诊断含脂质肝脏肿瘤的价值.材料和方法:回顾性分析34例含脂质肝脏肿瘤的MRI表现和术前或穿刺前诊断,并与病理对照.结果:T1WI 32例呈高信号、2例低信号,T2WI 32例呈高信号、1例等信号、1例低信号.用脂肪抑制后,15例肝细胞癌(HCC)、7例血管平滑肌脂肪瘤(HAML)、1例肝腺瘤和1个局灶结节性增生(FNH)T1WI的高信号完全消失,1例不典型腺瘤样增生结节局灶癌变和1例HAML出血囊变T1WI 高信号大部分消失,6例肝腺瘤和1个FNH病灶T1WI高信号无变化 .26例血供丰富,4例血供不丰富.14例HCC、2例腺瘤、7例HAML和1例FNH诊断正确,2例HAML诊断为良性肿瘤.结论:MRI能显示含脂质肝脏肿瘤的特征性表现,并正确诊断多数这类肿瘤.     

Fate of hypointense lesions on Gd-EOB-DTPA-enhanced magnetic resonance imaging

Purpose

To investigate the natural outcome and clinical implication of hypointense lesions in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI.

Materials and methods

Forty patients underwent Gd-EOB-DTPA-enhanced MRI for preoperative evaluation of HCC. Hypointense lesions in the hepatobiliary phase that were hypovascular 5 mm of more were extracted for follow-up. We performed a longitudinal study retrospectively for these lesions regardless of whether classical HCC developed or emerged in a different area from that of the lesions being followed.

Results

Thirty one patients displayed 130 hypointense lesions on MRI and only nine showed no hypointense lesions. In total, 17 (13.1%) of 130 hypointense lesions on MRI developed into classical HCC. The cumulative rates for these lesions to develop into classical HCC were 3.2% at 1 year, 11.1% at 2 years and 15.9% at 3 years. The total occurrence rates of classical HCC (25.8% at 1 year, 52.6% at 2 years and 76.4% at 3 years) were higher compared to those regarding only occurrence of classical HCC from hypointense lesions on MRI (10.0% at 1 year, 35.6% at 2 years and 44.6% at 3 years), although no significant difference was observed (p = 0.073).

Conclusions

Hypointense lesions that are detected in the hepatobiliary phase of Gd-EOB-DTPA-enhanced MRI have some malignant potential, although treating these lesions aggressively in patients who already have HCC may be too severe.     

Characterization of hepatic adenoma and focal nodular hyperplasia with gadoxetic acid

Purpose:

To characterize imaging features of histologically proven hepatic adenoma (HA) as well as histologically and/or radiologically proven focal nodular hyperplasia (FNH) using delayed hepatobiliary MR imaging with 0.05 mmol/kg gadoxetic acid.

Materials and Methods:

Five patients with six HAs with histological correlation were retrospectively identified on liver MRI studies performed with gadoxetic acid, and T1‐weighted imaging acquired during the delayed hepatobiliary phase. Additionally, 23 patients with 34 radiologically diagnosed FNH lesions (interpreted without consideration of delayed imaging) were identified, two of which also had histological confirmation. Signal intensity ratios relative to adjacent liver were measured on selected imaging sequences.

Results:

All six hepatic adenomas (100%), which had histological confirmation, demonstrated hypointensity relative to adjacent liver on delayed imaging. Furthermore, all of the FNH (including 34 radiologically proven, 2 of which were also histologically proven) were either hyperintense (23/34, 68%) or isointense (11/34, 32%) relative to the adjacent liver on delayed imaging. None of the FNHs were hypointense relative to liver.

Conclusion:

Distinct imaging characteristics of HA versus FNH on delayed gadoxetic acid‐enhanced MRI, with adenomas being hypointense and FNH being iso‐ or hyperintense on delayed imaging may improve specificity for characterization, and aid in the differentiation of these two lesions. J. Magn. Reson. Imaging 2012;36:686–696. © 2012 Wiley Periodicals, Inc.