【摘要】 目的 探讨在常规MRI扫描的基础上增加DWI序列对乙肝肝硬化背景微小肝癌（≤1 cm）的检测价值。方法 51例乙肝肝硬化患者共54个微小肝癌，同时行常规MRI（T₂WI+T₁WI双回波序列+动态增强）及DWI扫描。由2位阅片者采用双盲法分析常规MRI图像及联合常规MRI+DWI图像，记录病灶的信号特点、强化方式及阅片者的信心评分，比较2种成像模式下阅片者的信心评分及一致性，并通过ROC曲线评估阅片者对微小肝癌的诊断能力，以及检测微小肝癌的敏感性、特异性和阳性预测值。结果 增加DWI图像后：（1） 2位阅片者检测微小肝癌的信心评分提高，差异有统计学意义（P<0.05）,同时，2位阅片者检测微小肝癌的一致性增加。（2） 2位阅片者检测微小肝癌的ROC曲线下面积均提高，差异有统计学意义（P<0.05）。（3） 2位阅片者检测微小肝癌的敏感性及阳性预测值差异均无统计学意义（P>0.05）,特异性差异均有统计学意义（P<0.05）。结论 在常规MRI扫描的基础上增加DWI序列有助于提高对乙肝肝硬化背景微小肝癌诊断能力。更多还原

【Abstract】 Objective To assess the added value of diffusion weighted imaging（DWI）in combination with conventional magnetic resonance imaging（MRI）in detection of micro-small hepatocellular carcinomas（MHCC）.Methods A total of 51 hepatitis B induced cirrhotic patients with 54 MHCC lesions, all underwent conventional MRI（T₂WI+ T₁WI double eho sequences+ dynamic contrast enhancement）and DWI. Two separate blind image analyses of the conventional MRI set and the combined conventional MRI and DWI sets were performed. The signal characteristic of MHCC,the enhancement style, and the confidence scores for MHCC detection were recorded. Confidence scores of the two imaging sets for MHCC detection and consistency of the two observers were compared, diagnostic efficacy of each imaging set was evaluated by receiver operating characteristic（ROC）curve analysis, sensitivity, specificity and positive predictive values（PPV）were calculated and analyzed.Results（1）The addition of DWI led to a significantly（P<0.05）increasing confidence score with higher detecting of MHCC by both observers, and the consistency of two readers also increased.（2） The area under the ROC curve of the second imaging set was significantly higher（P<0.05）than that of the first set by both observers.（3）There were no significant differences（P>0.05）in sensitivity and PPV between the two image sets, significantly differences（P<0.05）was observed in specificity.Conclusion Adding DWI to conventional MRI may improve the diagnostic efficacy of MHCC with hepatitis B induced cirrhotic liver.更多还原