功能磁共振成像在乙型肝炎相关慢性肝病检测中的应用

目的 探讨功能磁共振成像指标与慢性乙型肝炎、肝硬化程度动态变化的关系，并与血清肝纤维化标志物作对照分析。方法 对47例慢性肝病患者[慢性乙型肝炎6例，肝硬化41例（其中ChildA级14例，ChildB级12例；ChildC级15例）]及10名正常人（对照组）进行扩散加权成像（DWI），用不同的b值及b值差计算肝脏表观扩散系数（ADC）。灌注加权成像（PWI）测量肝脏强化参数：到达灌注峰值时间（TP）、血容量分布及肝脏强化曲线最大上升斜率（MSI）。相位对比法（PC）测门静脉血流速度、每分钟流量。所有入选者同时检测血清肝纤维化标志物：透明质酸（HA），Ⅲ型前胶原（PCⅢ）、层黏连蛋白（LN）和Ⅳ型胶原（CⅣ）。结果 （1）DWI：Child C级肝硬化组与对照组比，ADC3差异有统计学意义（P〈0．01），Child A、B级肝硬化组与对照组之间ADC3差异也有统计学意义（P值均〈0．05）。慢性乙型肝炎组和Child C级肝硬化组间ADC3差异有统计学意义（P〈0．01）。（2）PWI：Child A、B、C级肝硬化较对照组TP明显延长（P值均〈0．01）。肝脏MSI比较，对照组明显大于Child A、B、C级肝硬化组，差异有统计学意义，P值均〈0．01。（3）Child A、B、C级肝硬化组门静脉血流速度较慢性乙型肝炎组和对照组显著下降，差异有统计学意义，P值均〈0．01。（4）Child A、B、C级肝硬化组HA较慢性乙型肝炎组和对照组显著升高，差异有统计学意义，P值均〈0．01）；Child A、B．C级肝硬化组LN也明显高于慢性乙型肝炎组和对照组，P值均〈0．01；Child A，B、C级肝硬化组PCⅢ指标较对照组显著升高，P值均〈0．01。结论 功能磁共振成像指标能反映出慢性乙型肝炎、肝硬化的动态变化，对肝硬化的诊断及临床治疗有重要的参考价值。

Functional MRI in chronic liver disease of hepatitis B patients

OBJECTIVE: To estimate the correlations between functional MRI (fMRI) parameters and the severity of chronic liver lesions of hepatitis B patients. METHODS: 47 hepatitis B patients [6 with chronic hepatitis, 41 with cirrhosis (14 with Child-Pugh class A cirrhosis; 12 with class B cirrhosis; and 15 with class C cirrhosis)] and 10 normal volunteers, referred for measurements of apparent diffusion coefficient (ADC) values of the liver, perfusion imaging parameters, portal flow parameters and serum markers of hepatic fibrosis were included in the study. Diffusion-weighted imaging (DWI) with different b values and b value remainder was performed. Time to peak (TP), maximum slope of increase (MSI) and distribution volume (DV) were measured with dynamic contrast material-enhanced MR imaging. Portal velocity and portal flow with phase contrast (PC) were measured. The patients' serum hepatic fibrosis markers, including hyaluronic acid (HA), type-III-procollagen (PC III), laminin (LN) and type-IV-collagen (C IV), were measured and analyzed together with the fMRI results. RESULTS: (1) The mean ADC3 in Child A, B, C cirrhosis patients was significantly lower than that in the controls (P < 0.05 in Child A, and P < 0.05 in Child B). (2) There was a significant increase of time to peak and a decrease of maximum slope of increase (P < 0.01) in the Child A, B, C patients than in the normal controls. (3) There was a significant decrease in portal velocity in cirrhotic patients as compared to that of the controls and chronic hepatitis patients (P < 0.01). (4) The mean HA in Child A, B, C cirrhosis patients was significantly higher than that in chronic hepatitis patients and in the controls (P < 0.01); The mean LN in Child A, B, C cirrhosis was also significantly higher than that in chronic hepatitis patients and in normal controls (P < 0.01); The mean PC III in Child A, B, C cirrhosis was significantly higher than that in the normal controls (P < 0.01). CONCLUSION: fMRI parameters can reflect some changes of the livers, therefore fMRI parameters are of value in clinical diagnosis and treatment of chronic hepatitis B patients.