磁共振T2值评估大鼠肝纤维化的应用价值

摘要

目的 探讨磁共振T2值评价大鼠肝纤维化的应用价值.材料与方法 连续注射四氯化碳诱导大鼠生成肝纤维化动物模型,根据病理结果对模型动物及其正常对照进行肝纤维化程度分期(S)、炎症活动分级(G)和肝脏脂肪变性分度(F).利用磁共振多回波梯度-自旋回波序列分析大鼠肝脏T2值与肝纤维化程度分期之间的关系.结果 肝纤维化模型建模成功的大鼠肝纤维化程度分期为S1～S4期,其炎症活动度分级均为G0或G1级,肝脏脂肪变性分度均为F3或F4级,肝纤维化模型动物的炎症活动度分级及肝脏脂肪变性分度差异无统计学意义(P＞0.05).各纤维化分期动物的T2值依次为:S0期(正常对照大鼠)(38.27±1.45) ms、S1期(42.08±2.63) ms、S2期(45.93±3.61) ms、S3期(50.23±2.23) ms和S4期(57.79±5.40) ms,各期T2值差异有统计学意义(F=31.903,P＜0.01);除S0期与S1期T2值差异无统计学意义(P＞0.05)外,其余各期两两比较差异均有统计学意义(P＜0.01);T2值与肝纤维化分期之间呈正相关(rs=0.921,P＜0.01).结论 T2值能定量评估肝纤维化程度.%Purpose To evaluate the feasibility of magnetic resonance T2 values in diagnosing hepatic fibrosis (HF).Materials and M1etdheds The models of HF were induced in rats by repetitive dosing of carbon tetrachloride.The stage of hepatic fibrosis (S),grade of inflammation (G) and degree of fatty liver (F) for the HF model animals and their normal controls were evaluated by pathology.The relationship between T2 values and liver fibrosis was analyzed by using multiple echo gradient spin echo sequences.Results According to the stage of hepatic fibrosis,the HF model rats were staged into S1-S4.The grade of inflammation of the HF model rats was G0 or G1,and the degree of fatty liver was F3 or F4,both of which had no statistical differences among the HF model rats at different fibrosis stages (P＞0.05).The T2 values for all rats including normal control rats in the stage of liver fibrosis from S0 to S4 were (38.27±1.45) ms,(42.08±2.63) ms,(45.93±3.61) ms,(50.23 ± 2.23) ms and (57.79± 5.40) ms,respectively,with a significant difference (F=31.903,P＜0.01).Except the T2 values had no significant difference between the S0 and S 1 stages (P＞0.05),the pairwise comparisons of the T2 values between the rest stages were statistically significant (P＜0.01).The T2 values were positively correlated with the stages of hepatic fibrosis (rs=0.921,P＜0.01).Conclusion The T2 value can quantitatively reflect the degree of hepatic fibrosis.