MRI对肝脏上皮样血管平滑肌脂肪瘤与肝细胞肝癌鉴别诊断的价值

目的 比较动态增强磁共振成像(DCE-MRI)和扩散加权成像(DWI)对肝脏上皮样血管平滑肌脂肪瘤(HEAML)和肝细胞肝癌(HCC)鉴别诊断的价值.方法 回顾性分析经手术病理证实的15例HEAML患者和50例HCC患者MR资料,术前均行DCE-MRI和 DWl扫描.观察记录2组病灶的大小、部位、边界、平扫信号特点(包括T1WI、T2WI及DWI),增强模式、中心血管影、有无早期静脉引流、"假包膜",计算表观扩散系数(ADC)值,并对2组病例上述MR征象进行统计学比较分析.结果 所有病例均为单发病灶.15个HEAML病灶8个显示早期静脉引流、11个显示中心血管征、6个有假包膜、5个为"快进快出"强化模式、10个为"快进慢出"强化模式,ADC平均值为(1.15±0.31)×10-3 mm2/s;50个HCC病灶中,6个显示早期静脉引流、5个显示中心血管征、45个有"假包膜"、29个为"快进快出"强化模式,ADC平均值为(1.23±0.29)×10-3 mm2/s.两者在病灶中心血管影、早期静脉引流、"假包膜"征方面差异有统计学意义(P<0.05),在病灶部位、大小、边界、平扫信号特点(包括T1WI,T2WI及DWI)、强化模式、ADC值方面差异无统计学意义(P>0.05).结论 DCE-MRI较DWI更有助于鉴别HEAML和HCC.     

肝脏上皮样血管平滑肌脂肪瘤的MRI征象分析

目的:分析肝脏上皮样血管平滑肌脂肪瘤(Epi-AML)的MRI特点。方法:回顾性分析经手术病理证实的10例(共11枚)肝脏Epi-HAML患者MRI资料,包括病灶的数目、部位、大小、外形、病灶实质部分T1、T2及扩散加权信号强度、是否含有脂肪成分、强化特征、病灶内血管、引流静脉情况、有无假包膜及周围肝实质有无肝硬化、脂肪肝背景。结果:9例患者为单发病变,1例为两枚病灶。7枚位于右叶,4枚位于左叶;10枚病灶呈圆形或椭圆形,境界清晰,T1WI低信号,T2WI高信号,9枚DWI高信号,3枚病灶内含有少量脂肪;动脉期11枚病灶均明显强化,强化模式9枚为"快进慢出"型;9枚病灶内可见点条状血管影,6枚病灶周边可见"早期引流静脉",3枚在门脉期和延迟期"假包膜"征;各有1例有肝硬化及脂肪肝背景。结论:少或无脂肪的境界清晰的富血供肿块、"快进慢出型"强化特征、病灶内血管影及早期引流静脉是肝脏,Epi-AML一定特征的MRI征象。     

肝脏血管平滑肌脂肪瘤的CT和MR表现

肝脏血管平滑肌脂肪瘤(HAML)是少见的肝脏间叶性肿瘤,肿瘤由厚壁血管、平滑肌和脂肪三种成分以HMB45组成103平滑肌细胞成分对于诊断有AML,虽然其有多种形态HAML细胞黑色素瘤相关单克隆抗体HMB45和A 103免疫组化染色阳性对于确定AML的诊断有重要意义.HAML的影像特征与其不同的组织成分构成相关,血管、平滑肌和脂肪三种成分构成的比例不同,其影像表现不同.尽管肝血管平滑肌脂肪瘤影像表现多样,但在动态增强成像表现为富血供且显示病灶内点条状血管影以及脂肪成分的存在是其重要的影像特征.一旦诊断肝脏血管平滑肌脂肪瘤,就应该予以积极随访或外科手术治疗.     

肝脏上皮样血管平滑肌脂肪瘤的影像学诊断

目的 研究肝上皮样血管平滑肌脂肪瘤的影像特征,以减少对该病的误诊.方法 对8例经手术病理证实为肝脏上皮样血管平滑肌脂肪瘤的临床及影像学资料进行回顾性分析.女6例,男2例,年龄56～68岁,平均62.5岁.7例肝上皮样血管平滑肌脂肪瘤行CT平扫及增强扫描,其中1例曾行MRI检查,1例仅行MRI检查.8例均误诊,其中4例术前误诊为肝癌(HCC)和肝血管瘤,3例误诊为局灶性结节增生(FNH),1例误诊为血管肉瘤.结果 肝上皮样血管平滑肌脂肪瘤具有一定特征性的表现:(1)CT、MRI平扫呈等低、低或等高密度(信号),边界光整,圆形或类圆形,大小约5～8 cm;(2)增强扫描动脉期呈明显或较明显均匀强化,少数可不均匀明显强化,中央或周边有明显强化的粗大畸形的血管;(3)强化方式为快进快出或快进慢出、持续性强化,仍有畸形血管可以辨别.结论 影像学结合临床资料对正确诊断肝脏上皮样血管平滑肌脂肪瘤有重要价值,少部分需要进行穿刺活检.     

肝脏上皮样血管平滑肌脂肪瘤的影像学表现与病理对照分析

目的探讨肝脏上皮样血管平滑肌脂肪瘤(epithelial angiomyolipomas,EAML)的影像学表现及病理特征,提高对该病诊断的准确性。方法回顾性分析9例经病理证实的肝EAML的临床表现及影像学资料。其中3例行MRI平扫和多时相动态增强扫描,5例行CT平扫和三期动态增强扫描,1例同时行CT和MR检查。9例均误诊,其中6例术前误诊为肝癌,1例误诊为血管瘤,1例误诊为局灶性结节增生(FNH),1例误诊为转移瘤。结果 9例肝EAML均为单发的类圆形肿块,边界清楚;6例位于肝右叶,3例位于肝左叶。CT平扫呈稍低密度;MRI平扫T1WI呈稍低信号,T2WI呈稍高信号;增强扫描动脉期呈明显不均匀强化,少数可均匀明显强化,6例动脉期可见早期引流静脉,8例动脉期或门脉期中央或周边可见明显强化的粗大畸形的血管;强化方式为快进快出或快进慢出。结论 EAML影像学表现具有一定特征性,结合临床资料,对术前正确诊断具有重要意义,但诊断有赖于穿刺活检。     

肝脏上皮样血管平滑肌脂肪瘤的影像学表现

目的 探讨肝脏上皮样血管平滑肌脂肪瘤(Epi-HAML)的影像学表现,旨在提高对该病的认识和诊断准确率. 方法 同顾性分析经手术病理证实的8例Epi-HAML的影像学及临床资料.其中4例行CT平扫和三期动态增强扫描,3例行MRI平扫和多时相动态增强扫描,1例行CT和MRI检查.结果 8例Epi-HAML中女7例,男1例.术前均误诊,其中4例术前误诊为肝癌,1例误诊为海绵状血管瘤,1例误诊为局灶性结节增生(FNH),2例误诊为腺瘤5例位于肝右叶,3例位于肝左叶.8例Epi-HAML均为单发,边界清楚.CT平扫呈稍低密度,2例密度均匀;2例病灶中间及边缘分别见局限性斑点及弧线样低密度影,CT值约-13 ～-17HU.MRI平扫T1WI呈稍低信号,T2WI呈稍高信号同反相位末见明显信号改变.增强扫描动脉期肿瘤呈不均匀或均匀明显强化.增强模式为“快进慢出”型5例、“快进快出”型3例.动脉期4例病灶可见“早期引流静脉”,2例在动脉期可见中心强化血管征 结论 Epi-HAML的影像学表现具有一定特征性,可与其他肝脏肿瘤相鉴别,但其诊断与鉴别仍主要依靠组织病理学及免疫组织化学检查.     

肝脏上皮样血管平滑肌脂肪瘤的影像学表现

目的:分析肝脏上皮样血管平滑肌脂肪瘤(HMEA)的影像学表现及其病理,以提高对该病的诊断水平。方法:回顾性分析5例经病理证实的HMEA的影像学表现及其病理。结果:5例均为女性,影像学特征有:①平扫呈低或稍高密度(信号),边缘光整,圆形或类圆形,大小约3.7～9.5cm;②增强扫描动脉期呈较明显或明显均匀强化,少数可不均匀明显强化,中央或周边可见粗大畸形的血管;③强化方式为快进快出或快进慢出、持续性强化,仍有畸形血管可以辨别。结论:HMEA多见于女性,其影像学表现具有一定特征,确诊仍有赖于病理组织学及免疫组织化学检查。     

混合型肝脏血管平滑肌脂肪瘤的CT和MRI诊断

目的 探讨肝脏血管平滑肌脂肪瘤(hepatic angiomyolipoma,HAML)CT和MRI的诊断价值.资料与方法回顾性分析经病理证实的8例肝脏HAML的CT和MRI表现.8例均行CT平扫和多时相动态增强扫描,其中4例同时行MRI平扫和多时相动态增强扫描.结果 8例均为单发混合型HAML,CT平扫均表现为低于周围正常肝组织的混杂低密度,灶内含有不同程度的脂肪密度,CT值-40～40HU.4例MRI平扫表现为稍长T1(含短T1)、稍长T2混杂信号,T1WI上高信号在使用脂肪抑制技术后完全消失.CT与MRI多时相动态增强扫描显示动脉期病灶均呈显著不均匀强化,门静脉期6例CT、3例MRI病灶呈持续或渐进性中重度强化,高于周围正常肝实质,2例CT、1例MRI病灶轻中度强化;3例HAML见假包膜,且在门静脉期及延迟期有轻度强化.结论 CT和MRI能显示混合型HAML的特征性表现并可在术前做出准确诊断.     

肝脏血管平滑肌脂肪瘤MRI表现

目的：总结分析肝脏血管平滑肌脂肪瘤（AML）的MRI表现,比较上皮样与非上皮样肝脏AML的MRI表现差异。方法：搜集经手术病理证实的肝脏AML患者15例,1l例行MRI检查,其中上皮样AML5例,非上皮样AML6例,1例非上皮样AML仅行MRI平扫,其余10例均行MRI平扫及动态增强扫描。结果：化学位移成像栓出7例肿瘤的脂肪成分,而频率饱和法仅检出3例肿瘤的脂肪成像。无脂肪型中上皮样与非上皮样AML各2例;少脂肪型中上皮样AML1例,非上皮样AML3例;富脂肪型中上皮样AML2例,非上皮样AML1例;上皮样与非上皮样AML脂肪含量相仿。10例行增强扫描的病例中动脉期强化9例,门脉期强化6例,延迟期强化5例,延迟期环形包膜样强化9例,动态增强曲线8例呈动脉期速升,门脉期及延迟期强化迅速减低。结论：上皮样与非上皮样AML影像学表现差异较小,MRI检出脂肪含量多寡难以作为肿瘤是否为上皮样AML的诊断标准。在MRI动态增强扫描中,上皮样AML与富血管平滑肌的经典型AML强化形式相似。     

Dynamic gadopentetate dimeglumine-enhanced MR imaging of hepatocellular carcinoma

Nineteen patients with 28 histologically proven hepatocellular carcinomas (HCCs) were examined using T1- and T2-weighted spin-echo sequences and dynamic gadopentetate dimeglumine-enhanced magnetic resonance imaging (MRI) performed by fast T1-weighted gradient-echo sequence (100/5/80°) which was performed before and repeatedly (12 sets of images) after intravenous bolus injection of gadopentetate dimeglumine (Gd-DTPA) over a period of 10 min. Enhancement of HCC was heterogeneous in 24 lesions (85.7%). Intra-lesional non-enhancing areas were seen in 18 cases (64%). A late-enhancing pseudocapsule was seen in 12 lesions (42.9%). In addition, two groups were distinguished in the examined HCCs: 16 lesions (57.1%) showed stronger enhancement compared to liver parenchyma with maximum positive lesion-to-liver contrast on the 15-s images, while 12 lesions (42.9%) had an enhancement less than normal liver with a maximum negative contrast on the 15-s images. We conclude that the morphologic features most frequently encountered in HCC on dynamic Gd-DTPA-enhanced MRI are inhomogeneity of enhancement, intra-lesional non-enhancing areas, and relatively late enhancement of a pseudocapsule. Taking the degree of enhancement to be representative of the degree of vascularity, we also conclude that HCC can appear either hypervascular or hypovascular in the early phase of the dynamic study. Correspondence to: B. Hamm     

MR imaging of hepatocellular carcinoma following transcatheter hepatic chemo-embolization

Transcatheter chemo-embolization (TCE) for hepatocellular carcinoma (HCC) was performed on 31 patients, and on 4 of the 31 patients, it was performed twice. The patients were examined by MR both before TCE and after TCE (1 week and 4-5 weeks respectively). On MR images, the change of the tumor signal intensity was classified into 3 groups. In group 1, (G1, 8 cases), obvious change of intensity was seen in the whole tumor. In group 2, (G2, 10 cases), it was seen in some parts of the tumor and in group 3, (G3, 17 cases), only a very slight change of intensity was seen in the whole tumor. In G1 and G2, the rate of AFP decrease was remarkable, but in G3, it was very slight. In G1 and G2, the change of the tumor signal intensity was divided into 2 types on a T2 weighted image. One, is the increase of the intensity, (6 cases). The other, is decrease of intensity, (12 cases). The former seemed to reflect the intra-tumoral hemorrhage accompanying tumor necrosis, the latter, seemed to reflect the coagulation necrosis. The ring of low and high intensity around the tumor appeared anew in 11 cases, and in 2 cases, it increased in size. These changes which have never been recognized on CT images, were thought to be a granulation tissue around the tumor. The influence of the accumulated lipiodol is slight for the change of intensity on the tumor.     

肝脏上皮样血管平滑肌脂肪瘤的MRI表现

目的:探讨肝脏上皮样血管平滑肌脂肪瘤(HEAML)的MRI特征.方法:回顾性分析经病理证实的47例HEAML的MRI平扫及增强扫描资料,其中7例另行钆塞酸二钠增强扫描,并与病理对照.结果:47例共54个病灶,43例(91.5％)单发,4例(8.5％)多发(1例2个,3例3个);位于肝右叶21个(38.9％),左叶29个...     

Dynamic 3DFT FISP MR imaging of hepatocellular carcinoma]

Dynamic 3 dimensional Fourier transformation (3DFT) FISP MR imaging was performed in 5 patients with hepatocellular carcinoma before partial hepatectomy. Immediately after 0.1 mmol/kg of Gd-DTPA was administered intravenously, 3DFT FISP images (TR/TE/flip angle/slice thickness, 20 msec/8 msec/30 degrees/2-4 mm) were obtained every 30 seconds until 150 sec. We correlated dynamic MR images of the 5 patients with gross and microscopic findings. Some regions in the tumor corresponding to viable cells showed high intensity enhancement and other regions corresponding to necrotic regions showed no enhancement on the early phase images. We concluded that dynamic 3DFT FISP MR imaging which had good spatial resolution was useful in evaluating the vascularity of the tumor.     

MR imaging of hepatocellular carcinoma

Forty-two patients with hepatocellular carcinoma (HCC) were examined by magnetic resonance (MR) imaging. The presence of tumor was suggested in 41 of 42 cases by a high-intensity area on T2 weighted spin-echo (SE) images with a repetition time (TR) of 1.6 s. Specific findings of HCC such as the presence of a capsule, mosaic pattern, and tumor thrombus in major veins were noted in 10, two, and seven cases, respectively. In six cases the tumor pattern changed from a well-defined mass to an irregular, ill-defined one according to pulse sequence (SE: echo time 35 and 70 ms; TR 1.6 and 0.4 s). In our early experience MR was almost equal to conventional X-ray CT in the detection of main or daughter lesions and in the determination of extent and characterization of HCC.     

MR扩散加权成像在肝细胞癌诊断中的应用价值

目的 探讨核磁共振扩散加权成像（MR DWI）技术在肝细胞癌诊断中的应用价值.方法 选取来我院就诊且经病理检查已证实的患有肝细胞癌的患者40例,患有肝血管瘤、肝囊肿的患者分别20例为研究对象,并选取同期来我院体检的肝脏正常的体检者20例作为健康对照组.对所有患者均进行MR扩散加权成像扫描,测定b值（扩散敏感系数）分别取50、400、800s/mm2时的信号强度、背景噪声等指标及表观扩散系数（ADC）值,比较不同b值时同-病变信号强度、质量指数及信噪比的差异,及最佳b值时不同肝脏病变的平均ADC的差异.结果 不同b值下的RM扩散加权扫描图像显示b=800s/mm2为本研究最佳肝脏扩散加权成像b值.临床应用RM扩散加权成像可以对肝细胞癌实质区和坏死区做出鉴别,且可以将肝细胞癌病症如肝血管瘤和肝囊肿等肝占位性病变相区分.结论 DWI在肝细胞癌诊断中具有特征性影像学表现,且对肝脏病变诊断具有较高检出效率和敏感性.     

肝脏单形性上皮样血管平滑肌脂肪瘤的影像表现

目的提高对肝脏单形性上皮样血管平滑肌脂肪瘤（HMEA）影像表现的认识和诊断准确率。方法对经手术病理证实的4例HMEA进行回顾性分析，讨论影像表现和病理之间的联系。结果4例HMEA中，2例误诊为肝细胞癌，1例误诊为局灶性结节增生，1例诊断正确。影像表现主要为：（1）平扫呈等低或等稍高密度的HMEA2例，强化模式呈“快进慢出”。病理特点足瘤内有丰富的窦隙状薄壁分隔微血管网，无分化成熟的脂肪细胞，1例伴厚壁的血管。（2）平扫呈低密度或低信号的HMEA2例，强化模式呈“快进快出”，中央可见粗大的动脉。病理特点为瘤中央有畸形粗大厚壁的动脉，无脂肪细胞夹杂其间。结论HMEA影像表现与病理结构直接相关，根据影像表现结合临床资料可对该病作出初步诊断，但确诊仍依赖病理组织学检查。     

Bright-dark ring sign in MR imaging of hepatic epithelioid hemangioendothelioma

We describe the imaging findings in a rare case of multifocal nodular form of hepatic epithelioid hemangioendothelioma on ultrasound (US) and dynamic contrast-enhanced spiral computed tomography (CT) and MRI. The nodules showed multilayered target appearance on MR images with prominent peripheral rim with high signal intensity (SI) on T1-weighted and very low SI on T2-weighted images, corresponding to thrombosed vascular channels. The above combination of imaging findings is to our knowledge distinct and should suggest the diagnosis of hepatic epithelioid hemangioendothelioma.