MR T_2 WI肝脏信号强度指标评估慢性乙型肝炎的价值

目的探讨MR脂肪抑制T2WI肝脏信号强度指标(SII)评估慢性乙型肝炎炎症活动度(G)和纤维化程度(S)的价值。资料与方法慢性乙型肝炎患者32例,正常18例。扫描序列主要为脂肪抑制T2WI,肝脏SII为肝脏与右侧背肌信号强度之比。结果肝脏SII平均0.966±0.172。多因素方差分析G分组F=8.608,P=0.000;S分组F=4.032,P=0.009;G和S交互作用F=2.374,P=0.050。偏相关示SII与G间r=0.622,P=0.000;与S间r=-0.361,P=0.011。接受者工作特性(ROC)曲线示SII诊断中重度肝炎曲线下面积=0.925,P=0.000,最佳诊断界点SII=0.97。结论 MR脂肪抑制T2WI肝脏SII与慢性乙型肝炎炎症活动度呈显著正相关,其判断中重度炎症活动的值为>0.97。     

磁共振灌注成像在鼠肝纤维化、肝硬化病理分级中的价值

目的:分析大鼠肝纤维化、肝硬化磁共振灌注成像(MR-PWI)参数特征,评价PWI对肝纤维化、肝硬化病理分级的价值.方法:清洁级SD大鼠100只,体重约150～200 g,雄性.将大鼠随机分为2组,对照组(n=16),实验组(n=84);实验组腹腔定点注射硫代乙酰胺(TAA),对照组同期腹腔注射相同剂量生理盐水.建模成功后实验组和对照组分批次进行肝脏常规磁共振扫描及PWI扫描.依据病理结果将肝脏损伤分为5组:肝纤维化0期(对照组)、肝纤维化Ⅰ期(S1),肝纤维化Ⅱ期(S2),肝纤维化Ⅲ期(S3),肝硬化结节期(S4),然后分析灌注参数与病理分级的相关性.结果:共69只大鼠(实验组57只,对照组12只)成功获取PWI图像并进行灌注参数测量,成功率69％(69/100).各期门静脉诸灌注参数之间差异有统计学意义(P＜0.05),各期肝实质诸灌注参数之间差异有统计学意义(P＜0.001).门静脉TTP及WOR与肝纤维化分级之间存在相关性(r=0.420、-0.464,P＜0.001).肝实质TTP及WIR与肝纤维化分级之间存在相关性(r=0.424、-0.488,P＜0.001).结论:MR-PWI参数与大鼠肝纤维化、肝硬化的分级有一定相关性.MR-PWI对评价肝纤维化分期具有一定的临床价值.     

慢性乙型肝炎患者的超声综合评分与病理分级分期的相关性

目的:研究慢性乙型肝炎患者超声综合评分与肝纤维化病理分期以及炎症活动度分级的关系.方法:197例慢性乙型肝炎患者经超声引导下肝组织活检,根据肝纤维化的程度和炎症活动度,将患者分为S0、S1、S2、S3、S4组和G1、G2、G3、G4组.活检前行肝脏超声检查,从肝包膜、肝边缘角、肝实质回声、肝静脉壁、胆囊壁5个方面进行综合评分,比较不同组别患者的超声综合评分,并将超声评分与肝组织活检病理结果进行相关性分析.结果:不同组别超声综合评分之间存在显著性差异(t＜0.05),超声综合评分与肝纤维化病理分期以及炎症活动度分级呈正相关(r分别为0.7891和0.6648,P＜0.05).结论:超声综合评分可较好地反映慢性乙型肝炎患者的纤维化程度和炎症活动度.     

肝细胞外基质体积分数定量评价肝纤维化的诊断价值

目的 探讨肝细胞外基质体积分数(fECVs)在无创定量评价肝纤维化程度方面的诊断价值.方法 选取肝脏穿刺确诊肝纤维化并进行常规肝脏多期动态增强CT扫描患者60例,通过平扫及平衡期(注射对比剂3 min后)计算肝实质(Eliver)及主动脉(Eaorta)绝对强化值,并通过以下公式计算fECV值:fECV(％)=Eliver/Eaorta(100-Hct[％]),分析各纤维化组间fECV值差异及其与肝脏纤维化程度的相关性,采用受试者工作特征曲线分析fECV值诊断肝纤维化程度的能力.结果 肝纤维化分期组间fECV值比较差异具有统计学意义(P＜0.05),S0∶S4、S1∶S4及S2∶S4差异有统计学意义;fECV值与肝纤维化程度呈正相关(r=0.468,P=0.001);fECV值诊断重度肝纤维化及早期肝硬化(S≥3及S=4)的敏感性和特异性分别为76％、68％及89％、63％,受试者工作特征曲线下面积分别为0.757及0.775.结论 fECV值可以作为常规肝脏多期动态增强CT检查中无创性评估肝纤维化的方法.     

The association of enlarged periportal lymph nodes on T2 WI with chronic hepatitis B

目的:探讨T2 WI肝门区淋巴结与慢性乙肝炎症活动度(G)和纤维化程度(S)的关系.方法:经病理证实的慢性乙型肝炎32例,健康成人18例(对照组).在MR脂肪抑制T2 WI上观察肝门区短径＞5 mm淋巴结的数目、大小和相对信号强度,并分析其与慢性乙型肝炎G和S的关系.结果:肝门区短径＞5 mm的淋巴结预示G2及以上炎症活动(P＜0.05),淋巴结数目≥2为最佳诊断点,敏感度和特异度分别为79.31％和90.47％;淋巴结的存在与S无关.淋巴结的大小与G有相关性(r=0.362,P=0.010),与S无相关性(r=-0.046,P=0.753);淋巴结的相对信号强度与G(r=0.260,P=0.071)和S(r=0.031,P=0.831)均无相关性.淋巴结的大小预示G2及以上炎症活动准确性较高(ROC曲线下面积=0.920,P＜0.001),以＞90 mm2为最佳诊断点,敏感度和特异度分别为89.66％和80.95％.结论:MR脂肪抑制T2 WI能显示慢性乙肝肝门区肿大淋巴结.肝门区出现2个及以上、短径＞5 mm淋巴结或淋巴结大小＞90 mm2提示G2及以上炎症活动.     

T_2WI肝门区淋巴结和慢性乙型肝炎的关系

目的:探讨T2WI肝门区淋巴结与慢性乙肝炎症活动度(G)和纤维化程度(S)的关系。方法:经病理证实的慢性乙型肝炎32例,健康成人18例(对照组)。在MR脂肪抑制T2WI上观察肝门区短径>5mm淋巴结的数目、大小和相对信号强度,并分析其与慢性乙型肝炎G和S的关系。结果:肝门区短径>5mm的淋巴结预示G2及以上炎症活动(P<0.05),淋巴结数目≥2为最佳诊断点,敏感度和特异度分别为79.31%和90.47%;淋巴结的存在与S无关。淋巴结的大小与G有相关性(r=0.362,P=0.010),与S无相关性(r=-0.046,P=0.753);淋巴结的相对信号强度与G(r=0.260,P=0.071)和S(r=0.031,P=0.831)均无相关性。淋巴结的大小预示G2及以上炎症活动准确性较高(ROC曲线下面积=0.920,P<0.001),以>90mm2为最佳诊断点,敏感度和特异度分别为89.66%和80.95%。结论:MR脂肪抑制T2WI能显示慢性乙肝肝门区肿大淋巴结。肝门区出现2个及以上、短径>5mm淋巴结或淋巴结大小>90mm2提示G2及以上炎症活动。     

MR成像在原发性胆汁性肝硬化评估中的综合作用

目的评估原发性胆汁性肝硬化(PBC)病人的MRI表现,判断扩散加权成像(DWI)对肝纤维化的评估价值。材料与方法复习44例病人MRI表现如下:门静脉周围T2WI高信号影、门静脉周围晕征(门静脉周围T1WI和T2WI低信     

ADC值联合肝纤四项对肝纤维化分期的评估

目的 评价MRI扩散加权成像(DWI)联合肝纤四项对肝纤维化评价的准确性.方法 将弥漫性肝病行腹部MRI检查(包括DWI)的患者30例作为研究对象.依炎症活动度(G)、纤维化程度(S)分级,将患者分为G0S0期、G1(S1～S2)期、G2(S1～S3)期、G3(S2～S4)期和G4S4期,分析扩散敏感系数(b值)分别为600 s/mm2和800 s/mm2时,不同病理分期患者表观扩散系数(ADC)值的变化;同时检测患者血清中透明质酸(HA)、Ⅲ型前胶原(PCⅢ)、Ⅳ型胶原(C-Ⅳ)和层黏连蛋白(LN)的变化,结合ADC值进行分析.结果 随肝纤维化程度加重,ADC值依次降低;随ADC值的变化,血清肝纤四项指标水平也呈现不同的变化.结论 ADC值联合血清肝纤维化指标能够准确评估肝纤维化分期.     

经颈静脉肝内门体分流术后肝脏及相关脏器时间-密度曲线变化的临床意义及价值

目的 探讨经颈静脉肝内门体分流术(TIPS)后肝脏及相关脏器时间-密度曲线(TDC)变化的临床意义及价值. 方法 对拟行TIPS的20例肝硬化患者于术前2～3天、术后1周分别行肝脏灌注扫描.记录并观察第一肝门下方(TIPS支架下端)门静脉主干层面门静脉、肝实质、脾实质等3个感兴趣区的TDC形态、达峰时间(TTP)和峰值(PV)的变化情况.结果 与TIPS术前比较,术后门静脉、肝脏、脾脏TTP提前(t/Z=3.322、2.242、-2.298,P=0.004、0.037、0.022)和门静脉PV增高(t=-2.613,P=0.017),差异有统计学意义;肝实质PV降低(t=1.137,P=0.270),脾脏PV升高(t=1.137,P=0.144),差异无统计学意义.脾脏TDC由术前的速升缓降型、缓升平台型、持续缓升型转变为术后速升缓降型.结论 门静脉、肝实质、脾实质TDC变化可直观地反映TIPS术后肝脏血流动力学变化特点.     

代偿期肝硬化MRI常规序列形态学分析和信号测量研究

目的 :探讨MRI常规序列形态学分析和信号测量对代偿期肝硬化的诊断价值。方法 :回顾性分析184例代偿期肝硬化患者(实验组)的上腹部MRI常规T1WI、FS-T1WI、T2WI和FS-T2WI图像,测量其信号强度,并与125例正常人(对照组)进行比较。结果:代偿期肝硬化T1WI及FS-T1WI示肝实质有稍高或高信号小或细小结节139例(75.54%);T2WI、FS-T2WI示肝实质有低信号小或细小结节78例(42.39%);肝脏表面不光滑,呈大小不等结节状或波浪状改变105例(57.07%);肝裂增宽58例(31.52%);肝叶比例失调86例(46.74%);肝脏缩小43例(23.37%);脾大156例(84.78%);门静脉高压征象15例(8.15%),包括门静脉、脾静脉增粗以及食管下段、胃底等静脉曲张。肝脏信号强度T1WI及FS-T1WI实验组显著低于对照组(P<0.05),T2WI及FS-T2WI显著高于对照组(P<0.05)。结论 :MRI常规序列形态学分析对代偿期肝硬化的诊断敏感且操作简便;肝脏信号强度在某种程度上可反映代偿期肝硬化肝脏的病理变化。     

Primary biliary cirrhosis: evaluation with T2-weighted MR imaging and MR cholangiopancreatography

Purpose

The aim of this retrospective study is to evaluate the role of T2-weighted MR imaging (MRI) and MR cholangiopancreatography (MRCP) findings in the diagnosis of primary biliary cirrhosis (PBC).

Materials and methods

The following T2-weighted MRI and MRCP findings: segmental hepatic atrophy/hypertrophy, irregular liver surface, parenchymal lace-like fibrosis, rounded low signal intensity lesions centering portal vein branches (periportal halo sign), periportal hyperintensity (cuffing), splenomegaly, ascites, lymphadenopathy, venous collaterals, and the configuration of intrahepatic biliary ducts were reviewed for their diagnostic significance by two observers in 13 female patients (mean age: 49 years) with PBC. Discordant readings of the observers were resolved at consensus.

Results

When parenchymal lace-like fibrosis and periportal halo sign were seen together the sensitivity of T2-weighted MR images was 69%. In six cases periportal hyperintensity (cuffing) and periportal halo sign were seen together. Segmental hypertrophy was present in nine patients and hepatic surface irregularity due to regenerative nodules were present in 10 patients. Lymphadenopathy was seen in 10, splenomegaly was seen in 5, collateral vascular structures were seen in 2 and minimal perihepatic free fluid was seen in 2 patients. MRCP images revealed various mild irregularity in the intrahepatic bile ducts in 8 patients and focal narrowing at the common bile duct level in 1 patient.

Conclusion

MRI and MRCP may support the clinical and laboratory findings of PBC even in the early stages of the disease. MRI can also be a choice of method for the recommended prolonged follow up.     

Chronic hepatosplenic schistosomiasis mansoni: magnetic resonance imaging and magnetic resonance angiography findings

PURPOSE: To evaluate the hepatosplenic manifestations and the portal venous system in patients with chronic infection by Schistosoma mansoni. MATERIAL AND METHODS: A cross-sectional observational study was performed in 28 patients with chronic hepatosplenic schistosomiasis submitted to magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the abdomen. Images were interpreted independently by two radiologists to determine the reproducibility of image interpretation and who evaluated the presence of morphological alterations in the liver and spleen, such as hepatosplenomegaly, hepatic fissure widening, periportal fibrosis, and the presence of siderotic nodules. Interobserver and intra-observer agreement were measured with the kappa and intraclass correlation tests. Evaluation of venous collateral pathways and portal and splenic veins was done in consensus by both examiners. RESULTS: Observers identified enlargement of the left lobe (78.5-92.8%) and caudate-to-right-lobe ratio (78.5-92.8%), irregularity of hepatic contours (89.2-96.4%), fissure widening (89.2-100%), and splenic siderotic nodules (84.2%). Splenomegaly, heterogeneity of hepatic parenchyma, peripheral hepatic vessels, and periportal fibrosis were observed in 100% of patients. MRI findings presented almost perfect interobserver (kappa = 0.65-1) and intra-observer (kappa = 0.73-1 for observer 1, and kappa = 0.65-1 for observer 2) agreement for the variables analyzed. MRA showed the presence of collateral pathways in the majority of patients (71.4%) along with widening of portal and splenic veins. CONCLUSION: Using MRI, hepatosplenic alterations in schistosomiasis are characterized by heterogeneity of hepatic parenchyma, presence of peripheral perihepatic vessels, periportal fibrosis, splenomegaly, siderotic nodules, and the presence of venous collateral pathways.     

肝移植后MR征象的探讨

目的:探讨原位肝移植术后MR征象形成及临床意义。方法:13例原位肝移植术后患者均用SE序列及FSE序列常规扫T1WI及脂肪抑制T2WI,部分选用磁共振胰胆管成像(MRCP)、钆喷替酸葡甲胺(Gd-DTPA)动态增强3D MRA检查,分析各序列图像特点。结果:13例患者均在脂肪抑制T2WI上出现门静脉周围间隙增宽,并伴有长T1、长T2信号;1例出现肝内胆管的弥漫性囊柱状扩张;10例出现移植肝周围及叶间裂少量积液,部分患者合并胸腔积液;10例MRCP示胆道明显或稍狭窄,其中5例为吻合口狭窄,2例为肝门部淋巴结压迫所致,3例ERCP结果与之相符;5例见可疑胆湖。2例ERCP发现吻合口胆漏而MRCP表现为阴性;4例追踪发现肝内肿瘤复发或出现远处转移灶;1例诊断为局灶性肝坏死。结论:通过对肝移植术后门周间隙增宽,弥漫性胆管扩张及胆汁瘤等征象进行探讨,为临床评价移植物功能,诊断胆漏提供了一定的信息。     

细胞色素P450 1B1基因多态性与子宫内膜癌易感性研究

目的研究细胞色素P4501B1基因外显子2密码子119（G-T）、外显子3密码子432（C-G）多态性与子宫内膜癌遗传易感性的关系。方法采用等位基因特异性聚合酶链反应（AS-PCR）法对72例子宫内膜癌患者和80例对照者进行CYP1B1基因密码子119（G-T）、密码子432（C-G）突变分析,用SP免疫组化法进一步研究雌激素受体（ER）、孕激素受体（PR）的表达是否受CYP1B1基因多态性的影响。结果CYP1B1基因密码子119、432中等位基因G、T和C、G在子宫内膜癌组和对照组分布的差异有显著性（χ^2=16.817,P=0.000;χ^2=9.133,P=0.003）,其中等位基因T、G使患子宫内膜癌危险性分别增加了3.052和2.213倍。CYP1B1基因密码子119G/T各基因型分布两组间有显著性差异（χ^2=18.267,P〈0.01）,纯合突变T/T、G/G基因型、杂合突变G/T、C/G基因型与野生G/G、C/C基因型相比,患子宫内膜癌的危险度分别提高了4.258、3.871倍和3.235、2.214倍。此外,119T/T、G/T基因型、432G/G、C/G基因型者ER阳性表达率高于119G/G、432C/C野生基因型,有显著性差异（χ^2=6.750,P=0.034;χ^2=6.977,P=0.031）。结论CYP1B1基因密码子119、432突变等位基因与子宫内膜癌的发生有一定关联,突变基因型增加了子宫内膜癌的发病风险,且与ER的表达相关。     

肝星状细胞在非酒精性脂肪性肝炎患者肝组织中的表达

探讨肝星状细胞（HSC）在非酒精性脂肪性肝炎（NASH）患者肝穿组织中的活化情况，并研究HSC的活化与炎症活动度以及纤维化的关系。将40例NASH患者的肝穿刺标本按炎症活动度分为G1和G2组，按照纤维化分级分为S0，S1和S2组，用多克隆抗－突触素标记HSC，采用免疫组织化学检测HSC的表达情况，HSCs主要分布在小叶中央区的窦壁上，HSCs的表达量与炎症活动度平行（G2＞G1，P＜0．05），HSC的活化虽然与纤维化的程度有关，但并不完全匹配，NASH患者的肝穿刺标本中有HSC的活化，NASH的肝纤维化与HSC的活化有密切关系，并且与小叶内和汇管区的炎症活动度呈正比。     

Hepatic iron deposition on magnetic resonance imaging: correlation with inflammatory activity

PURPOSES: To define the relation between pathologic inflammatory activity and magnetic resonance imaging (MRI) grades of iron deposition in patients with liver cirrhosis. PATIENTS AND METHODS: In 53 patients with biopsy-proven liver cirrhosis, T2*-weighted gradient echo MRI (echo time > or =6 milliseconds) was reviewed. Grading of parenchymal iron deposition and siderotic nodules in the liver and liver-to-skeletal muscle signal intensity ratios were compared with pathologically defined inflammatory activity. RESULTS: The MRI grade of hepatic siderotic nodules correlated significantly with the grade of periportal inflammation (r = 0.301, P < 0.05) but not with the grade of piecemeal necrosis. The grade of parenchymal iron deposition was not correlated with the grade of periportal inflammation or piecemeal necrosis. There was a nonsignificant trend toward correlation between the histologic grade of hepatic iron content and the grades of periportal inflammation and piecemeal necrosis. CONCLUSION: MRI grading of siderotic nodules correlates with inflammatory activity in cirrhotic patients.     

Chronic hepatitis B: correlation of abnormal features on T2-weighted imaging and dynamic contrast-enhanced imaging with hepatic histopathology

Objectives

To investigate the correlations between abnormal features on liver magnetic resonance (MR) T2-weighted imaging (T2WI) and dynamic contrast-enhanced (DCE) imaging and the pathological findings in chronic hepatitis B.

Materials and methods

Sixty-seven patients with chronic hepatitis B and 18 normal controls who were undergone an abdominal MR imaging were analyzed retrospectively. Patchy hyperintensities, linear and reticular hyperintensities in liver and periportal edema on T2WI and abnormal intrahepatic enhancement signals on DCE imaging were noted. The correlations between the abnormal features detected on hepatic T2WI and DCE imaging, and the levels of inflammatory activity and fibrosis were determined.

Results

Logistic regression analysis showed increased patchy hyperintensities (B = 1.869, P = 0.001) on T2WI and patchy enhancement (B = 1.596, P = 0.004) at the arterial phase along with increased inflammatory activity. However, linear and reticular hyperintensities (B = 2.356, P = 0.000) on T2WI, and meshwork enhancement (B = 2.191, P = 0.000) at the equilibrium phase, all correlated with fibrosis. Moreover, periportal edema mainly correlated with the inflammatory activities (B = 2.635, P = 0.001).

Conclusions

In chronic hepatitis B patients, patchy hyperintensities on T2WI, periportal edema, and patchy enhancement at the arterial phase can predict moderate-to-severe inflammatory activities, whereas intrahepatic linear and reticular hyperintensities on T2WI, and meshwork enhancement at the equilibrium phase can predict moderate-to-severe fibrosis.

     

超声微泡肝内渡越时间无创性评价肝纤维化程度的可行性

目的探讨超声造影(CEUS)微泡肝内渡越时间评价肝纤维化程度的可行性。方法根据Scheuer评分将83例慢性乙肝患者分为无纤维化组(S0期)、轻度肝纤维化组(S1～S2期)、中度肝纤维化组(S3期)和重度肝纤维化组(S4期),分别行CEUS检查,计算对比剂肝动脉-肝静脉渡越时间(HA-HVTT)、门静脉-肝静脉渡越时间(PV-HVTT)及肝实质-肝静脉渡越时间(PA-HVTT),比较各组渡越时间与肝纤维化程度的相关性。结果无纤维化组HA-HVTT、PV-HVTT、PA-HVTT与对照组无显著差异(P>0.05),轻度肝纤维化组、中度肝纤维化组、重度肝纤维化组HA-HVTT、PV-HVTT、PA-HVTT与对照组均有显著差异(P<0.05)。PV-HVTT在无纤维化组、轻度肝纤维化组、中度肝纤维化组、重度肝纤维化组两两比较均有差异(P<0.05),HA-HVTT、PA-HVTT在无纤维化组与轻度肝纤维化组之间、轻度肝纤维化组与重度肝纤维化组之间有差异(P<0.05)。HA-HVTT、PV-HVTT和PA-HVTT与纤维化程度均呈负相关(r=-0.53,r=-0.71,r=-0.48,P<0.01)。结论 CEUS获取的肝内渡越时间是无创性评价肝纤维化程度的参考依据。