【作者】 齐晓辉；

【导师】 时高峰；

【作者基本信息】 河北医科大学 ， 影像医学与核医学， 2010， 硕士

【摘要】 目的:通过对伴肝硬化的临床诊断或可疑小肝癌患者进行CT增强扫描、CT灌注成像、MR扩散加权成像及MR动态增强扫描,评价各种检查技术对肝脏小病灶的检出能力;得出CT灌注参数值及ADC值诊断小肝癌的最佳界值;综合多种影像学对比研究,评价不同影像学方法对小肝癌的诊断价值。方法:42名临床诊断或怀疑小肝癌患者,进行CT增强、CT灌注、MR弥散成像、MR多期增强4种检查方法。CT灌注成像采用GE公司的Lightspeed 32排多层螺旋CT机,造影剂剂量50ml,注射速率5.0ml/s。CT三期增强扫描:经肘静脉注入造影剂后分别延时25s、60s、110s对肝脏进行动脉期、门脉期及延时期扫描。造影剂剂量90ml,注射速率3.0 ml/s。MRI扫描采用SIEMENS AVANTO 1.5T超导磁共振成像仪,行常规MRI及DWI扫描,弥散加权成像于增强检查前进行,取b值为0、800s/mm2。随后行T1WI压脂及T2WI压脂序列的扫描。MR动态增强扫描:MR增强扫描采用顺磁性对比剂钆喷酸葡胺(Gd-DTPA,0.1mmol/kg),用磁共振专用高压注射器经肘静脉注影,流速3ml/s,同时注入生理盐水30ml。由两名有多年工作经验的放射学医师采用盲法对CT及MR采集的图像进行分析,包括病变的部位、大小、密度(信号)程度。测量病灶和硬化肝实质的CT灌注值、ADC值及时间-密度(信号)曲线类型分布。以病理结果或临床诊断为金标准对CT和MR增强扫描的诊断价值进行评价。结果:42名患者共检出52个病灶,其中手术病理或结合临床实验室检查结果证实小肝癌41例,不典型增生结节4例,血管瘤7例。1 CT增强共检出52个病灶,平扫检出36个病变,35个病变表现为低密度,16个病变表现为等密度、1个病变表现为高密度;动脉期检出42个病变, 11个病灶为低密度,10个病灶为等密度,31个病灶显示为高密度;门脉期检出35个病变,30个病灶为低密度,17个病灶为等密度,5个病灶为高密度;延迟期检出41个病变,41个病灶表现为低密度,11个病灶为等密度。平扫、动脉期、门脉期及延迟期各期的检出率分别为69.23%、80.77%、67.31%、78.85%。2小肝癌的BF、BV、MTT、PS、HAF、HAP、HPP值分别为(270.792±168.110)ml.min-1、(22.713±10.298)ml.100g-1、(10.347±5.048)s、(41.752±25.408)ml.min-1.100g-1、0.810±0.231、181.986±148.230、48.805±85.780,肝硬化肝质的BF、BV、MTT、PS、HAF、HAP、HPP值分别为(181.990±136.763) ml.min-1、(18.232±8.848) ml.100g-1、(11.839±5.899)s、(41.270±16.081) ml.min-1.100g-1、0.323±0.250、62.983±96.138、119.007±121.189,小肝癌与肝硬化肝质的灌注参数测量结果显示小肝癌的HAF、HAP大于瘤周肝组织,HPP小于肝实质的HPP,且两者间差异有统计学意义(p<0.05),余灌注参数值在两者间差异无显著性意义。经ROC曲线统计学方法分析,以HAF的诊断效能为最佳, HAF≥0.642时诊断小肝癌,敏感度为88.9%,特异度为88.9%。3时间-密度曲线类型为速升速降型曲线的病灶共有10例,其中9例为小肝癌,1例为良性病变;速升持续型曲线共有16例,15例为小肝癌,1例为良性病变;缓慢上升型曲线有7例,3例为小肝癌,4例为良性病变。经统计学分析病变的良恶性与时间-密度曲线类型之间有关联性,且时间-密度曲线类型为速升速降型和速升持续型有助于对小肝癌的诊断。4 42名患者进行MRI检查,增强扫描共检出病灶52个,DWI检出50个病灶,49个病灶表现为高信号,2个病灶为等信号,1个病灶为稍低信号;T1WI检出42个病灶,15个病灶为高信号,10个病灶为等信号,27个病灶为低信号;T2WI检出44个病灶,38个病灶为高信号,8个病灶为等信号,6个病灶为低信号。DWI、T1WI、T2WI序列对肝脏小病灶的检出率分别为94.34%、79.25%、83.02%。5小肝癌与肝实质的ADC值测量结果显示,小肝癌的ADC值为1.071±0.248×10-3 mm2/s,肝实质的ADC值为1.185±0.273×10-3 mm2/s,良性病变的ADC值为1.490±0.562×10-3 mm2/s,小肝癌的ADC值小于肝硬化实质和良性病变的ADC值,且它们之间差异有统计学意义(p值分别为0.005和0.017)。对其ROC曲线进行数据分析,当诊断良恶性的ADC临界值设为1.176×10-3 mm2/s时,敏感度为70%,特异度为81.2%。6时间-信号曲线类型为速升速降型的有21例,均为小肝癌;速升持续型的有10例,其中7例为小肝癌,3例为良性病变;缓慢上升型的有7例,其中3例为小肝癌,4例为良性病变。经统计学分析病变的良恶性与时间-信号曲线类型之间有关联性,且速升速降型和速升持续型的时间-信号曲线类型有助于小肝癌的诊断。7从单纯三种方法对良恶性的诊断结果来看,MR增强的诊断特异度、阳性预测值及诊断正确率较高,分别是80%、93.75%及95%。联合试验后以CT增强和DWI、MR增强和DWI联合后的特异度、阳性预测值及诊断正确率较高,分别为90%、96.43%、90%和90%、96.55%、92.5%,且高于其他方法。但是经过配对四格表的卡方检验得出P值均>0.05,它们对小肝癌的诊断结果之间无显著差异。结论:1 CT多期增强扫描中动脉期及延迟期有助于小病灶的检出。2 CT灌注成像有助于小肝癌的诊断,尤其是肝动脉分数的测定,当其值≥0.642时,诊断敏感度为88.9 %,特异度为88.9 %。3小肝癌的时间-密度(信号)曲线类型分为三型:速升速降型、速升持续型、缓慢上升型,病变的良恶性与时间-密度曲线类型之间有关联性。如果病变的曲线类型为速升速降或速升持续型,有助于小肝癌的诊断。4 MR弥散成像对肝脏病变的检出率高于常规T1WI和T2WI。5小肝癌的ADC值小于良性病变,ADC值有助于良恶性的诊断,将诊断界值定为1.176×10-3 mm2/s时,敏感度为70%,特异度为81.2%。6 CT增强、MR增强和MR扩散加权成像及两两联合试验对小肝癌的诊断结果之间差异无统计学意义,尚不能认为它们对小肝癌的诊断结果不同。7临床怀疑小肝癌的患者在经济情况允许下可行MR增强扫描,弥散成像可做补充检查技术;如果患者经济情况不允许的情况下可行CT增强扫描,诊断困难时加做MR弥散成像。更多还原

【Abstract】 Objective:Through the clinical diagnosis small hepatocellular carcinoma or suspicious small hepatocellular carcinoma patients of cirrhosis with,CT scan, CT perfusion imaging, diffusion-weighted imaging and MR dynamic scanning, evaluate the detectability of various checks on small lesions of the liver,comprehensive research on a wide variety of imaging contrast, evaluate diagnosis value of different imaging methods for small hepatocellular carcinoma.Materials and Methods: 42 patients of clinical diagnosis small hepatocellular carcinoma or suspicious small hepatocellular carcinoma patients underwent CT scan, CT Perfusion imaging, DWI and MR dynamic scanning. CT Perfusion using GE Lightspeed32 MSCT,contrast dose was 50ml,the injection rate was 5.0ml/s.CT enhanced scanning:The scan delay time for arterial phase, portal venous phase and lag phase was20 s, 60 s and 110s respectively. Injecting the contrast medium into the ulnar vein with the high– pressure syringe, the rate was 3ml/ s, and the dose was90ml. MRI scans using SIEMENS AVANTO 1.5T scanner, including T1WI,T2WI and diffusion weighted imaging. The DWI was performed with different b value(0 , 800s / mm2). The dynamic MRI examination with gadolinium-DTPA(Gd-DTPA) 0.1ml/kg, the rate was 3ml/ s.Two observers indepently interpreted the images of CT and MRI,separately, Including lesions of parts, size, density (signal) degree. CT Perfusion parameter values ,ADC values , Time-density curve type of lesions and cirrhotic liver parenchyma were measured .Results: 42 patients were checked out 52 lesions, the diagnosis of whieh inelude 41 casesOf SHCC,4 cases of dysplastic nodules ,7 cases of hemangioma.1 52 cases of SHCC were detected totally.in unenhance phase 35 SHCC presented hypoattenuated, 16 SHCC presented isoattenuated,1 SHCC presented hyperattenuated;in artery phase, 11 SHCC presented hypoattenuated, 10 SHCC presented isoattenuated,31 SHCC presented hyperattenuated ;in portal vein phase 30 SHCC presentedhypoattenuated, 17 SHCC presented isoattenuated,5 SHCC presented hyperattenuated and in delayed phase 41 SHCC presented hypoattenuated, 11 SHCC presented isoattenuated. The sensitivity of detection in unenhanced and three phases were 69.23%、80.77%、67.31%、78.85%.2 BF、BV、MTT、PS、HAF、HAP、HPP of SHCC was(270.792±168.110)ml.min-1、(22.713±10.298)ml.100g-1、(10.347±5.048)s、(41.752±25.408)ml.min-1.100g-1、0.810±0.231、181.986±148.230、48.805±85.780 respectively, BF、BV、MTT、PS、HAF、HAP、HPP BF、BV、MTT、PS、HAF、HAP、HPP of cirrhotic liver parenchyma was (181.990±136.763) ml.min-1、(18.232±8.848) ml.100g-1、(11.839±5.899)s、(41.270±16.081) ml.min-1.100g-1、0.323±0.250、62.983±96.138、119.007±121.189 respectively.SHCC’s HAF and HAP higher than those of cirrhotic liver parenchyma ,HPP lower than rhotic liver parenchyma ( p < 0. 05) . Otherwise ,no significant difference was seen in the other perfusion parameters ( p > 0. 05). After a statistical approach to analysis of the ROC curve ,the diagnostic effectiveness of HAF was the best. Using the HAF value of 0. 642 as the diagnostic threshold ,the sensitivity and specificity reached88.9% and 88.9 % respectively.3 The Time-density curve had there types including rapid increase and rapid decrease, slowly initial, sustained enhancement. The type of rapid increase and rapid decrease was 10 cases which 9 SHCC and 1 benign lesion. The type of sustained enhancement was 16 cases which 15 SHCC and 1 benign lesion. The type of slowly initial was 7 cases which 3 SHCC and 4 benign lesion. Through statistical analysis there has relationship between the benign or malignant lesions and time-density curve type, the rapid increase and rapid decrease and sustained enhancement type is helpful to the SHCC’s diagnosis.4 52 cases of SHCC were detected totally.49 lesions showed as hyperintense, 2 lesions showed as isointense,1 lesion showed as hypointense on DWI.15 lesions showed as hyperintense,10 lesion showed as isointense,27 lesions showed hypointense as onT1WI.38 lesions showed as hyperintense,8 lesion showed as isointense,6 lesions showed as hypointense onT2WI.The sensitivity of detection in DWI,T1WI and T2WI were 94.34%、79.25%、83.02%.5 The mean ADC value of SHCC、cirrhotic liver parenchyma、benign lesion was1.071±0.248×10-3mm2/s,1.185±0.273×10-3mm2/s ,1.490±0.562×10-3 mm2/s espectively.There was statistically significant difference in ADC value between SHCC lesions and cirrhotic liver parenchyma,SHCC lesions and benign lesion(p=0.005,p=0.017.When the ADC critical value of diagnosis benign and Malignant lesion was 1.176×10-3mm2/s,the sensitivity and specificity reached 70% and 81.2 % respectively.6 The Time-signal curve had there types including rapid increase and rapid decrease, slowly initial, sustained enhancement. The type of rapid increase and rapid decrease was 21 SHCC lesions. The type of sustained enhancement was 10 cases which 7 SHCC and 3 benign lesion. The type of slowly initial was 7 cases which 3 SHCC and 4 benign lesion.Through statistical analysis there has relationship between the benign or malignant lesions and time-density curve type, the rapid increase and rapid decrease and sustained enhancement type is helpful to the SHCC’s diagnosis.7 the specificity and positive predice value of MR enhancement scanning was 80%、93.75% respectively. The specificity and positive predice value of union CT enhancement scanning and DWI,MR enhancement scanning and DWI was 90%、96.43% and 90%、96.55%,was higher than one method。But p>0.05.Conclusion:1 CT arterial phase imaging and delay phase imaging is useful for finging small lesions.2 CT perfusion imaging ,especially HAF measurement ,was helpful in detecting SHCC. Using the value of 0. 642 as the diagnostic hreshold ,the sensitivity and specificity of HAF reached 88.9%and 88.9% respectively.3 The Time-density(signal) curve had there types including rapid increase and rapid decrease, slowly initial, sustained enhancement.Through statistical analysis there has relationship between the benign or malignant lesions and time-density curve type, the rapid increase and rapid decrease and sustained enhancement type is helpful to the SHCC’s diagnosis.4 The sensitivity of detection in DWI is higher than T1WI and T2WI.5 ADC values of malingnat tumors were lower than that of benign lesions. ADC value was helpful to differentiating malignant tumor from benign lesion. Using the value of 1.176×10-3 mm2/s as the diagnostic hreshold ,the sensitivity and specificity reached 70%and 81.2% respectively.6 The specificity and positive predice value of union CT enhancement scanning and DWI,MR enhancement scanning and DWI was higher than other methods,but can’t think the diagnosis results of three methods and union diagnosis on malingnat and benign lesions have different。7 Clinical suspect small hepatocellular carcinoma patients can does MR enhancement scanning if economic circumstances allowed,DWI can as supplementary inspection technology.If patients’economic circumstances doesn’t allowed,then can does CT enhancement scanning, difficult to diagnose then does DWI.更多还原