增强MRI扫描在乙型肝炎肝硬化背景下对原发性肝癌的诊断价值分析*

目的 研究采用钆塞酸二钠(Gd-EOB-DTPA)增强磁共振成像(MRI)对乙型肝炎肝硬化背景下原发性肝癌(PLC)的诊断价值。方法 2018年12月～2020年12月我院收治的乙型肝炎肝硬化背景下肝脏局灶性病变患者147例,均行Gd-EOB-DTPA肝脏增强MRI扫描,观察病灶强化特点和各序列信号强度,包括T1加权像(T₁WI)、T2加权像(T₂WI)及动脉期、门脉期、肝胆特异期和磁共振弥散加权成像(DWI)病灶的信号强度。采用受试者工作特征(ROC)曲线下面积(AUC)分析上述信号特征对PLC的诊断效能。结果 在147例患者中,发现PLC者102例,病灶大小为0.9～2.9 cm,平均为(1.8±0.6)cm,肝脏异型性增生结节45例,病灶大小为0.8～2.5 cm,平均为(1.4±0.2)cm;增强MRI扫描显示,84例表现为动脉期病灶呈低或等强化,门静脉期或延迟期呈低强化,63例表现为动脉期明显强化,门静脉期或延迟期未廓清;PLC组病灶T₁WI低信号、T₂WI高信号、DWI高信号、动脉期高强化和肝胆期低信号表现占比分别为50.0%、79.4%、82.4%、52.9%和94.1%,显著高于非PLC组(20.0%、20.0%、26.7%、20.0%和20.0%,P＜0.05);ROC分析结果显示病灶T₁WI低信号(AUC=0.670,敏感度=0.451)、T₂WI高信号(AUC=0.817,敏感度=0.745)、DWI高信号(AUC=0.754,敏感度=0.863)、动脉期高强化(AUC=0.693,敏感度=0.520)和肝胆期低信号(AUC=0.891,敏感度=0.892)对PLC具有一定的诊断效能(P＜0.05)。结论 增强MRI扫描在乙型肝炎肝硬化背景下早期发现PLC具有重要的诊断价值,临床应不断总结其特点变化,提高早期诊断率。     

多模态MRI对肝硬化增生性结节与小肝癌的鉴别诊断价值探讨

目的 探讨应用多模态磁共振成像(MRI)鉴别诊断肝硬化增生性结节(DN)与小肝癌(sHCC)的价值。方法 2016年12月～2021年12月我院收治的肝硬化伴肝内结节病变患者71例,以细针穿刺或术后组织病理学检查为金标准诊断。所有患者接受多模态MRI检查,比较动态增强(DCE-MRI)扫描参数,记录纯扩散系数(D值)、伪扩散系数(D*值)和表观扩散系数(ADC)变化。结果 在71例患者中,经病理学检查诊断sHCC者45例(63.4%),DN者26例(36.6%);sHCC病灶ADC值、D值和D*值分别为(0.81±0.19)×10^-3mm²/s、(0.91±0.21)×10^-3mm²/s和(46.26±10.13)×10^-3mm²/s,显著小于DN病灶【分别为(1.34±0.33)×10^-3mm²/s、(1.22±0.24)×10^-3mm²/s和(80.69±13.24...     

82例脑实质结核和肺癌脑转移瘤的MRI鉴别

目的 探讨MRI,尤其是增强MRI及弥散加权成像（diffusion weighted imaging,DWI）对脑实质结核及肺癌脑转移瘤的诊断与鉴别。方法 对42例脑实质结核和40例肺癌脑转移瘤患者,行MRI平扫、钆喷酸葡胺（Gd-DTPA）增强和DWI扫描。分析2者MRI表现特点,测量病灶各部分的表观扩散系数（apparent diffusion coefficient,ADC）值和病灶与对侧相应部位正常脑实质ADC值的比值（relative apparent diffusion coefficient,rADC值）,采用SPSS 13.0软件进行统计学t检验和卡方检验。结果 42例脑实质结核均为多发性结节,82.56%（374/453）病灶直径<1.0 cm;T₁WI增强图像上33.77%（153/453）的病灶呈均匀结节状强化、66.23%（300/453）呈环形强化,环壁厚薄较均匀、内外壁较光滑,约36.42%（165/453）的病灶周围存在不同程度水肿,以轻、中度为主。而32.50%（13/40）的肺癌脑转移瘤呈单发结节,41.01%(57/139)病灶直径<1.0 cm,T₁WI增强图像上4.32%(6/139)病灶呈均匀结节状强化、9.35%(13/139)呈不均匀斑片状强化、86.33%(120/139)病灶呈环形强化,仅19.17%(23/120)的瘤壁厚薄较均匀,余表现为壁毛糙或伴壁结节,75.54%(105/139)的病灶周围存在水肿,且以中、重度水肿为主。脑实质结核实性部分、壁平均ADC值［分别为（0.97±0.15）×10^-3 mm²/s和（1.07±0.20）×10^-3mm²/s］,均低于肺癌脑转移瘤的实性部分、壁ADC值［分别为（1.10±0.25）×10^-3mm²/s和（1.28±0.32）×10^-3mm²/s］,相应t值分别为3.648、5.051,P值均<0.001,差异有统计学意义。结论 增强MRI可显示脑实质结核及肺癌脑转移瘤病灶的不同形态特点,DWI和ADC值能反应2种疾病组织微观结构变化,有助于两者的鉴别。     

胸膜结核瘤的MRI表现特征分析

目的 探讨胸膜结核瘤的MRI表现特征,以提高其诊断水平。方法 收集湖南省胸科医院2018年1月至2019年12月经病理学和(或)病原学证实或临床诊断(依据临床症状体征、免疫学检查结果,以及诊断性抗结核药品治疗有效进行综合诊断)的87例胸膜结核瘤患者。将其中资料完整的60例患者作为研究对象,男41例,女19例;年龄13~78岁,中位年龄27岁。其中8例胸膜病变经手术后病理检查确诊,43例经胸膜活检病理检查确诊,9例为临床诊断患者。所有患者均进行了结核病相关实验室检查、胸部CT平扫、MRI平扫及增强扫描检查,分析评价患者的临床及胸部MRI表现特征。结果 60例患者MRI表现为单发病灶47例(78.3%),多发病灶13例(21.7%)。共74个病灶,其中右下肺37个(50.0%)病灶,34个病灶(45.9%)呈类圆形;51个病灶(68.9%)与胸膜呈宽基底相贴,边缘光滑,病灶基底部胸膜有移行性增厚。60例患者中,13例(21.7%)为未成熟结核瘤,T₁WI呈等或稍低信号,T₂WI、表现弥散系数(ADC)图像呈稍高信号,弥散加权成像(DWI)呈等信号,弥散不受限;增强检查呈斑点状强化或结节状均匀强化。29例(48.3%)为中心凝固性坏死结核瘤,T₁WI呈等或稍低信号,T₂WI、ADC 图像呈混杂高信号,DWI呈等信号,弥散不受限,增强检查呈不均匀结节状强化或环形强化;18例(30.0%)为中心液性坏死结核瘤,T₁WI呈低信号,T₂WI、ADC图像呈高信号, DWI呈混杂高信号,弥散受限,增强检查呈环形强化。2例(3.3%)可见多个结核瘤灶融合,形成脓肿,破溃至胸膜外脂肪间隙和(或)胸壁,ADC图像呈低信号,DWI呈高信号,弥散受限,增强检查呈环形和分隔样强化。结论 胸膜结核瘤具有一定的MRI表现特征,MRI在判断胸膜结核瘤累及范围及其所处病理阶段有优势。     

MRI动态增强联合DWI筛查老年胃癌淋巴结转移

目的观察老年胃癌淋巴结转移患者的磁共振成像(MRI)动态增强表现,分析MRI动态增强联合弥散加权成像(DWI)筛查诊断患者淋巴结转移的价值。方法回顾分析2017年10月至2019年10月经手术病理确诊60例老年胃癌患者,根据术后淋巴结转移情况分为转移组(n=21)与未转移组(n=39),在术前均接受MRI动态增强扫描与DWI扫描,分析MRI动态增强与DWI单独、联合筛查老年胃癌患者淋巴结转移的价值。结果转移组接受MRI动态增强扫描,病灶平均直径为(18.71±7.11)mm;多呈不规则形状,多检出毛刺征,病灶增强早期呈不均匀快速强化,少部分可见集簇状强化,多为肿块样病变;转移组最大增强斜率(MSI)值低于未转移组,当扩散敏感因子b分别为400、800 s/mm~2时,转移组表观扩散系数(ADC)值均低于未转移组,差异均有统计学意义(P0.05);受试者工作特征(ROC)曲线显示,MSI对应的ROC曲线下面积(AUC)为0.886,b值分别为400、800 s/mm~2,对应的ADC相应的AUC分别为0.770、0.952,均0.7,诊断效能高。各参数对应的最佳阈值分别为230.15、1.20、1.12;联合诊断的灵敏度、准确度、阴性预测值高于二者单独使用,且一致性指数Kappa值为0.757,与金标准一致性最好。结论 MRI动态增强联合DWI筛查老年胃癌淋巴结转移准确度、灵敏度更高,与手术病理结果的一致性更好,更具诊断价值。     

MRI检查及ADC值对肝腺瘤诊断的意义

目的分析MRI检查及ADC值对肝腺瘤诊断的意义。方法以21例经病理检查证实的肝腺瘤患者为研究对象,观察患者术前和活检诊断结果、MRI表现,计算表观扩散系数(ADC),对比以上检查与病理检查结果。结果 2例患者存在肝硬化表现,1例患者9个病灶,5例2个病灶,15例患者为单个病灶。26个病灶内脂质成分多,8个病灶脂质成分少。术前19例患者确诊为良性肝腺瘤,2例考虑为局灶性结节增生。18例病灶直径3 cm,10例病灶直径在3~5 cm,6例病灶直径5 cm。T1WI信号低信号30例,高信号4例;T2WI扫描低信号11例,高信号23例;Gd-DTPA增强扫描,动脉期病灶信号明显强化,门静脉期病灶低信号12例,高信号22例;延迟期扫描病灶低信号12例,高信号22例;DWI扫描病灶低信号21例,高信号13例。可见假包膜样强化病灶14例,假包膜样强化未明确20例。34例病灶平均ADC值为(1.704±0.330)×10~(-3)mm~2/s,病灶周边正常肝实质ADC值为(1.357±0.214)×10~(-3)mm~2/s,病灶ADC值与病灶周边肝实质ADC值比值1。结论 MRI检查联合病灶ADC值测量可为诊断肝腺瘤提供更为准确的参考依据,提高临床诊断肝腺瘤的准确率。     

Analysis of MRI characteristics of pleural tuberculoma

目的 探讨胸膜结核瘤的MRI表现特征,以提高其诊断水平。方法 收集湖南省胸科医院2018年1月至2019年12月经病理学和(或)病原学证实或临床诊断(依据临床症状体征、免疫学检查结果,以及诊断性抗结核药品治疗有效进行综合诊断)的87例胸膜结核瘤患者。将其中资料完整的60例患者作为研究对象,男41例,女19例;年龄13~78岁,中位年龄27岁。其中8例胸膜病变经手术后病理检查确诊,43例经胸膜活检病理检查确诊,9例为临床诊断患者。所有患者均进行了结核病相关实验室检查、胸部CT平扫、MRI平扫及增强扫描检查,分析评价患者的临床及胸部MRI表现特征。结果 60例患者MRI表现为单发病灶47例(78.3%),多发病灶13例(21.7%)。共74个病灶,其中右下肺37个(50.0%)病灶,34个病灶(45.9%)呈类圆形;51个病灶(68.9%)与胸膜呈宽基底相贴,边缘光滑,病灶基底部胸膜有移行性增厚。60例患者中,13例(21.7%)为未成熟结核瘤,T₁WI呈等或稍低信号,T₂WI、表现弥散系数(ADC)图像呈稍高信号,弥散加权成像(DWI)呈等信号,弥散不受限;增强检查呈斑点状强化或结节状均匀强化。29例(48.3%)为中心凝固性坏死结核瘤,T₁WI呈等或稍低信号,T₂WI、ADC 图像呈混杂高信号,DWI呈等信号,弥散不受限,增强检查呈不均匀结节状强化或环形强化;18例(30.0%)为中心液性坏死结核瘤,T₁WI呈低信号,T₂WI、ADC图像呈高信号, DWI呈混杂高信号,弥散受限,增强检查呈环形强化。2例(3.3%)可见多个结核瘤灶融合,形成脓肿,破溃至胸膜外脂肪间隙和(或)胸壁,ADC图像呈低信号,DWI呈高信号,弥散受限,增强检查呈环形和分隔样强化。结论 胸膜结核瘤具有一定的MRI表现特征,MRI在判断胸膜结核瘤累及范围及其所处病理阶段有优势。     

ADC差值法鉴别乳腺良恶性病变价值研究

目的探讨病灶周围组织与病灶表观扩散系数(apparent diffusion coefficient,ADC)差值在乳腺良恶性病变鉴别诊断中的价值。方法回顾性分析60例经手术及病理证实的乳腺病变患者的MR资料,通过分析病变的弥散加权成像(diffusion weighted imaging,DWI)的ADC值及ADC差值,并经统计学处理,比较两者的差异。结果 60个病灶中有32个恶性,28个良性,应用ADC值法最佳诊断值为1.30×10-3mm2/s,诊断的敏感度、特异度、准确率分别为93.8%、75.0%、85.0%;应用ADC差值法最佳诊断值为0.47×10-3mm2/s,诊断的敏感度、特异度、准确率分别为96.0%、82.1%、90.0%。结论 ADC差值法在评价乳腺良恶性病变有较高的诊断价值,可以有效弥补ADC值法诊断的不足,可作为功能成像DWI分析方法的有效补充,作为乳腺疾病的常规诊断方法。     

扩散加权成像序列图像纹理分析鉴别诊断乳腺良恶性肿瘤的价值

目的探讨扩散加权成像序列(DWI)图像纹理分析鉴别诊断乳腺良恶性肿瘤的价值。 方法回顾性分析泰州市人民医院手术病理证实的28例乳腺良性肿瘤与28例恶性肿瘤的DWI图像的影像特征及纹理特征。采用MaZda软件提取所有患者DWI图像中肿瘤病灶的直方图与灰度游程矩阵参数,包括均值(mean)、方差(variance)、偏度(skewness)、峰度(kurtosis)和第1、10、50、90、99百分位数(Pere.1%、Pere.10%、Pere.50%、Pere.90%、Pere.99%)及短游程因子(SRE)、长游程因子(LRE)、灰度不均匀度(GLNU)、游程长不均匀度(RLNU)、游程中的图像分数(fraction)(包括水平、垂直、45dgr、135dgr 4个方向),采用独立样本t检验(正态分布数据)或非参数检验Mann-Whitney U检验(偏态分布数据)分析良恶性肿瘤病灶DWI图像纹理参数的差异,提取差异有统计学意义的纹理特征参数,使用ROC曲线分析有统计学意义的纹理参数鉴别良恶性肿瘤的诊断效能,运用多变量Logistic回归分析对差异有统计学意义的纹理参数进行建模并绘制ROC曲线评价模型效能。 结果直方图参数中的方差(variance)与灰度游程矩阵参数中的游程长不均匀度(RLNU)(包括水平、垂直、45dgr、135dgr 4个方向)在两组间的差异有统计学意义(P<0.05),其中游程长不均匀度水平方向(HRLNU)以447.5517为阈值时诊断效能最佳,对应的AUC、灵敏度和特异度分别为0.874、85.71%、78.58%;通过对差异有统计学意义的纹理特征参数建立多参数Logistic回归诊断模型,对应的AUC、灵敏度及特异度为0.940、96.40%、82.10%。 结论DWI图像纹理分析鉴别诊断乳腺良恶性肿瘤具有良好的应用价值。     

磁共振扩散加权成像诊断四氯化碳诱导的兔肝纤维化的价值分析

目的探讨磁共振扩散加权成像(DWI)对肝纤维化的诊断价值。方法采用四氯化碳注射法建立家免肝纤维化模型每次实验抽取模型组家免7□8只和对照组家免2□3只进行DWI检查,共对30只肝纤维化成模组和10只对照组家免进行了DWI检查测算不同b值(分别为300、500和1000s/mm~2)时DWI的表观扩散系数(ADC)值;行DWI后12h内处死家免行肝组织病理学检查,按肝纤维化病理分期结果进行分组,比较不同分期动物ADC值的差异,采用Spearman相关分析探讨ADC值变化和纤维化分期之间的相关性,运用受试者工作特性(ROC)曲线评估ADC值预测S_2及以上肝纤维化和S_3及以上肝纤维化的诊断效能。结果ADC值与纤维化分期之间呈负相关性取b值=500 s/mm~2时相关性最高(r=0.795,P=0.000);在不同b值情况下肝纤维化≤S_1与≥S_2之间、纤维化≤S_2与≥S_3之间肝脏ADC值差异均有统计学意义(均P0.05);当b值=500 s/mm~2时,ADC值诊断≥S_2肝纤维化的ROC曲线下面积(AUC)为0.912,以ADC值=1.58×10~(-3)mm~2/s为截断点,其诊断肝纤维化的敏感性为90.2%特异性为75.0%;ADC值诊断≥S_3肝纤维化的AUC为0.920,以ADC值=1.43×10~(-3)mm~2/s为截断点,其敏感性为93.0%特异性为80.0%。结论ADC值可以用于诊断肝纤维化分期值得进一步研究。     

Prediction of different stages of rectal cancer: Texture analysis based on diffusion-weighted images and apparent diffusion coefficient maps

BACKGROUND It is evident that an accurate evaluation of T and N stage rectal cancer is essential for treatment planning. It has not been extensively investigated whether texture features derived from diffusion-weighted imaging(DWI) images and apparent diffusion coefficient(ADC) maps are associated with the extent of local invasion(pathological stage T1-2 vs T3-4) and nodal involvement(pathological stage N0 vs N1-2) in rectal cancer.AIM To predict different stages of rectal cancer using texture analysis based on DWI images and ADC maps.METHODS One hundred and fifteen patients with pathologically proven rectal cancer, who underwent preoperative magnetic resonance imaging, including DWI, were enrolled, retrospectively. The ADC measurements(ADC_(mean), ADC_(min), ADC_(max)) as well as texture features, including the gray level co-occurrence matrix parameters, the gray level run-length matrix parameters and wavelet parameters were calculated based on DWI(b = 0 and b = 1000) images and the ADC maps.Independent sample t-tests or Mann-Whitney U tests were used for statistical analysis. Multivariate logistic regression analysis was conducted to establish the models. The predictive performance was validated by receiver operating characteristic curve analysis.RESULTS Dissimilarity, sum average, information correlation and run-length nonuniformity from DWI_(b=0) images, gray level nonuniformity, run percentage and run-length nonuniformity from DWI_(b=1000) images, and dissimilarity and run percentage from ADC maps were found to be independent predictors of local invasion(stage T3-4). The area under the operating characteristic curve of the model reached 0.793 with a sensitivity of 78.57% and a specificity of 74.19%. Sum average, gray level nonuniformity and the horizontal components of symlet transform(SymletH) from DWI_(b=0) images, sum average, information correlation,long run low gray level emphasis and SymletH from DWI_(b=1000) images, and ADC_(max), ADC_(mean) and information correlation from ADC maps were identified as independent predictors of nodal involvement. The area under the operating characteristic curve of the model reached 0.802 with a sensitivity of 80.77% and a specificity of 68.25%.,CONCLUSION Texture features extracted from DWI images and ADC maps are useful clues for predicting pathological T and N stages in rectal cancer.     

Using receiver operating characteristic curves to evaluate the diagnostic value of the combi-nation of multislice spiral CT and alpha-feto-protein levels for small hepatocellular carcinoma in cirrhotic patients

BACKGROUND: The various combination of multiphase enhancement multislice spiral CT (MSCT) makes the diagno-sis of a small hepatocellular carcinoma (sHCC) on the back-ground of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein (AFP) level could increase the diagnostic ef-ficiency for sHCC.METHODS: This study included 35 sHCC patients and 52 cir-rhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists em-ploying a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the diag-nostic value of the three MSCT combination modes (arterial phase+portal-venous phase, arterial phase+delayed phase, arterial phase+portal-venous phase+delayed phase) and AFP levels for sHCC on the background of liver cirrhosis.RESULTS: The area under ROC curve (AUC), sensitivity, and specificity of the combination of arterial phase+portal-venous phase+delayed phase were 0.93, 93%, and 82%, re-spectively. The average AUC of the arterial phase+portal-venous phase+delayed phase combination was significantly greater than that of the arterial phase+portal-venous phase(AUC=0.84, P=0.01) and arterial phase+delayed phase (AUC=0.85, P=0.03). Arterial phase+portal-venous phase had a smaller AUC (0.84) than arterial phase+delayed phase (0.85), but the difference was insignificant (P=0.15). After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC.CONCLUSIONS: The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.     

小肝癌MR信号值与微血管侵犯相关性分析

目的分析小肝癌MR信号值与微血管侵犯(microvascular-invasion,MVI)的相关性。方法收集整理2010年12月至2019年1月解放军总医院第五医学中心小肝癌手术切除且于术前1周至1个月内行MR动态增强扫描检查的患者33例,根据病理诊断分为微血管侵犯组和非微血管侵犯组,进一步分为甲胎蛋白(AFP)阳性组和阴性组,测量并计算术前MR图像T1WI、T2WI、DWI序列及动态增强扫描动脉期、门脉期、延迟期病变信号值与相邻肝背景信号值的比值。结果33例患者中微血管侵犯22例,非微血管侵犯组11例;AFP阳性组17例,AFP阴性组16例。AFP阳性病例微血管侵犯与非微血管侵犯组间动脉期强化和延迟期强化信号特征差异有统计学意义(P<0.05),而T1WI序列、T2WI、DWI序列病变信号特征差异无统计学意义(P<0.05);AFP阴性病例T1WI序列、T2WI、DWI序列及动态增强扫描各期病变信号特征差异无统计学意义(P<0.05)。结论微小肝癌MR动态增强扫描病变强化特征可用于预测病变是否存在微血管侵犯。     

Diffusion-weighted magnetic resonance imaging without bowel preparation for detection of ulcerative colitis

AIM: To evaluate the accuracy of diffusion-weighted imaging(DWI) without bowel preparation,the optimal b value and the changes in apparent diffusion coefficient(ADC) in detecting ulcerative colitis(UC).METHODS: A total of 20 patients who underwent 3T magnetic resonance imaging(MRI) without bowel preparation and colonoscopy within 24 h were recruited.Biochemical indexes,including C-reactive protein(CRP),erythrocyte sedimentation rate,hemoglobin,leucocytes,platelets,serum iron and albumin,were determined.Biochemical examinations were then performed within 24 h before or after MR colonography was conducted.DWI was performed at various b values(b = 0,400,600,800,and 1000 s/mm2).Two radiologists independently and blindly reviewed conventional- and contrast-enhanced MR images,DWI and ADC maps; these radiologists also determined ADC in each intestinal segment(rectum,sigmoid,left colon,transverse colon,and right colon).Receiver operating characteristic(ROC) analysis was performed to assess the diagnostic performance of DWI hyperintensity from various b factors,ADC values and different radiological signs to detect endoscopic inflammation in the corresponding bowel segment.Optimal ADC threshold was estimated by maximizing the combination of sensitivity and specificity.MRfindings were correlated with endoscopic results and clinical markers; these findings were then estimated by ROC analysis.RESULTS: A total of 100 segments(71 with endoscopic colonic inflammation; 29 normal) were included.The proposed total magnetic resonance score(MR-score-T) was correlated with the total modified Baron score(Baron-T; r = 0.875,P 0.0001); the segmental MR score(MR-score-S) was correlated with the segmental modified Baron score(Baron-S; r = 0.761,P 0.0001).MR-score-T was correlated with clinical and biological markers of disease activity(r = 0.445 to 0.831,P 0.05).MR-score-S 1 corresponded to endoscopic colonic inflammation with a sensitivity of 85.9%,a specificity of 82.8% and an area under the curve(AUC) of 0.929(P 0.0001).The accuracy of DWI hyperintensity was significantly greater at b = 800 than at b = 400,600,or 1000 s/mm2(P 0.05) when endoscopic colonic inflammation was detected.DWI hyperintensity at b = 800 s/mm2 indicated endoscopic colonic inflammation with a sensitivity of 93.0%,a specificity of 79.3% and an AUC of 0.867(P 0.0001).Quantitative analysis results revealed that ADC values at b = 800 s/mm2 differed significantly between endoscopic inflamed segment and normal intestinal segment(1.56 ± 0.58 mm2/s vs 2.63 ± 0.46 mm2/s,P 0.001).The AUC of ADC values was 0.932(95% confidence interval: 0.881-0.983) when endoscopic inflammation was detected.The threshold ADC value of 2.18 × 10-3 mm2/s indicated that endoscopic inflammation differed from normal intestinal segment with a sensitivity of 89.7% and a specificity of 80.3%.CONCLUSION: DWI combined with conventional MRI without bowel preparation provides a quantitative strategy to differentiate actively inflamed intestinal segments from the normal mucosa to detect UC.     

磁共振扩散加权成像在前列腺癌诊断和鉴别诊断中的价值

目的 探讨磁共振扩散加权成像(DWI)和表观弥散系数(ADC)值在前列腺癌诊断与鉴别诊断中的应用价值.方法 46例经手术病理或穿刺活检证实的前列腺疾病患者行DWI检查,其中前列腺增生(BPH)21例,慢性前列腺炎9例,前列腺癌16例,扩散敏感分数值800 s/mm2.依病理结果,将前列腺外周带六分区归类为正常区、增生区,炎症区、癌区,测量每个分区的ADC值,癌与非癌组之间进行受试者操作特征曲线(ROC)分析.结果 各组ADC值分别为,BPH外周带(2.20±0.29)×10-3mm2/s,中央带(1.66±0.14)×10-3 mm2/s,炎症区(1.95±0.34)×10-3 mm2/s,癌区(1.24±0.32)×10-3 mm2/s,组间ADC值两两比较,差异均有统计学意义(均P＜0.01);ROC曲线上临界点取1.49×10-3 mm2/s,诊断的敏感性达86.8%,特异性为94.0%,ROC曲线下面积0.945±0.010.结论 前列腺DWI及ADC值可用于前列腺肿瘤的诊断和鉴别诊断,具有很高的临床应用价值.

Abstract：

Objective To explore the application of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) value in the diagnosis and differential diagnosis of prostatic cancer. Methods Diffusion-weighted echo-planar imaging (EPI) sequences were performed in 46 patients, including 21 cases of benign prostatic hyperplasia (BPH), 9 cases of chronic prostatitis and 16 cases of prostate cancer. DWI were obtained with a b-factor of 800 s/mm2. According to the pathological results obtained by ultrasound guided biopsy, the peripheral zone of prostate was divided into six parts by orientations and they were divided into noncancerous, hyperplasia, prostatitis and cancerous groups. The ADC value of each region was measured and analyzed with one-way ANOVA and ROC analysis. Results Acceptable images for ADC measurement were obtained in all cases.The mean ADC values of prostatic peripheral zone, prostatic central gland, inflammatory area and cancerous area were (2.20±0. 29)×10-3 mm2/s, (1.66±0.14)×10-3 mm2/s, (1.95±0.34)×10-3 mm2/s and ( 1.24 ± 0.32) × 10-3 mm2/s, respectively. There were statistically significant differences in ADC values between the inter-groups (P＜0. 01 ). With ROC cut point setting to 1.49 ×10-3 mm2/s, the diagnostic sensitivity and specificity for prostate cancer were 86. 8% and 94. 0%, the area under the ROC curve (AUC) was 0. 945±0. 010. Conclusions ADC value might be useful to evaluate prostate cancer. DWI has an important clinical application value in the diagnosis and differentiation of prostate cancer.