围绝经期女性腰椎骨强度磁共振定量研究

Study on MR quantitative technique in evaluating the lumbar spine strength of perimenopausal women

目的探讨基于磁共振脂肪定量技术(mDixon-quant)评估围绝经期女性腰椎骨髓脂肪分数FF值及T2*值进行骨质疏松(OP)诊断的应用价值。方法收集围绝经期女性57人总计228个椎体,均行双能X线吸收法(DXA)和腰椎mDixon-quant序列检查,分别测量L1~L4椎体的骨密度(BMD)、T值、FF值、T2*值。根据T值将所有围绝经期女性分为骨量正常组(116个椎体)、骨量减低组(80个椎体)及骨质疏松组(32个椎体)。3组间FF值、T2*值比较用单因素方差分析,用Spearman相关性分析FF值、T2*值与BMD的相关性,用受试者工作特征曲线(ROC)评价两者对骨量减低的诊断效能。结果FF值、T2*值及BMD 3组间比较差异有统计学意义(P<0.05);FF值与BMD呈负相关(r=-0.614,P<0.05),T2*值与BMD亦呈负相关(r=-0.462,P<0.05);FF值及T2*值诊断骨量减低AUC分别为0.821、0.774,95%CI分别为0.759~0.883、0.706~0.841。结论运用磁共振mDixon-quant技术可以定量测量FF值及T2*值,分别从骨密度及骨质量两方面间接评估围绝经期女性腰椎骨强度的变化特点,为诊断OP提供客观依据。

Objective To evaluate the value of magnetic resonance fat quantitative technique(mDixon-Quant)in diagnosing osteoporosis(OP)in perimenopausal women by measuring the lumbar bone marrow fat fraction(FF)and T2*value.MethodsA total of 228 vertebral bodies were collected from 57 perimenopausal women.All subjects underwent dual energy X-ray absorption(DXA)and lumbar mDixon-Quant sequence scanning simultaneously,and BMD,T,FF and T2*values of vertebral bodies(L1~L4)were measured.The patients were divided into normal bone mass group,low bone mass group and osteoporosis group according to T value and vertebral bodies.One factor analysis of variance was used to compare the FF value and T2*value among three groups,Spearman correlation analysis was used to analyze the correlation between FF value and T2*value and BMD,and the receiver operating Characteristic curve(ROC)was used to evaluate the diagnostic effectiveness of the two groups.ResultsThere were significantly difference in FF,T2*and BMD among three groups(P<0.05).FF was negatively correlated with BMD(r=-0.614,P<0.05),and T2*was negatively correlated with BMD(r=-0.462,P<0.05).The values of FF and T2*were 0.821,0.774,and 95%CI were respectively 0.759~0.883 and 0.706~0.841.ConclusionThe magnetic resonance mDixon-Quant technique can be used to quantitatively measure FF value and T2*value,and it can indirectly evaluate the changes of bone strength in perimenopausal women from bone density and bone mass respectively.It has certain clinical application value and provides objective basis for clinical diagnosis of OP.