基于多回波M-Dixon quant技术和T 2-mapping技术鉴别抗肌萎缩蛋白病分型的研究

A study on the identification of dystrophin disease typing based on multiechoic M-Dixon quant technology and T 2-mapping technology

目的:本研究探讨MRI多回波M-Dixon quant技术和T 2-mapping技术鉴别抗肌萎缩蛋白病分型的应用价值。方法:纳入抗肌萎缩蛋白病患儿共75例,其中杜氏肌营养不良(DMD)50例,贝氏肌营养不良症(BMD)25例。所有受试对象均进行大腿肌肉T 1WI-Dixon、多回波M-Dixon quant和T 2-mapping成像,并测量右侧大腿14块肌肉(臀大肌、阔筋膜张肌、股外侧肌、股中间肌、股内侧肌、股直肌、缝匠肌、长收肌、大收肌、股薄肌、半膜肌、半腱肌、股二头肌长头、股二头肌短头)的FF值、T2值。采用两独立样本比较的Mann-Whitney U检验比较DMD组和BMD组各肌肉FF值、T2值及14块肌肉平均FF值、T2值的差异,并绘制14块肌肉平均FF值、T2值的受试者工作特征(ROC)曲线,计算曲线下面积(AUC),分别评估曲线对DMD和BMD的鉴别诊断效能。结果:①DMD组以臀大肌FF值最高,其次是大收肌、股四头肌,以股薄肌、缝匠肌及长收肌最低;BMD组以臀大肌FF值最高,其次是股内侧肌,以股薄肌、长收肌最低。②DMD组以臀大肌T2值最高,其次是大收肌、股四头肌,以股薄肌、半腱肌最低;BMD组以臀大肌T2值最高,其次是股内侧肌,以股薄肌、半腱肌最低。③除缝匠肌及长收肌以外(P>0.05),DMD组其余12块肌肉FF值、14块肌肉平均FF值均高于BMD组,差异具有统计学意义(P<0.05)。DMD组各肌肉T2值及14块肌肉平均T2值均高于BMD组,差异具有统计学意义(P<0.05)。14块肌肉平均FF值、T2值鉴别DMD组与BMD组的AUC分别为0.709(0.591~0.828)、0.924(0.857~0.992),以14块肌肉平均T2值的鉴别二者效能最高,最佳临界值为41.55 ms,灵敏度86%,特异度88%。结论:多回波M-Dixon quant技术和T 2-mapping技术均可高效的鉴别抗肌萎缩蛋白病患儿,基于T 2-mapping技术的肌肉T2值测量具有更高的诊断效能,具有一定的临床意义。

Objective:To investigate the application value of MRI multiecho M-Dixon quant technology and T 2-mapping technology in the classification of dystrophin pathies.Methods:A total of 75 children with dystrophin disease were enrolled,including 50 cases of DMD(duchenne muscular dystrophy,DMD)and 25 cases of BMD(becker muscular dystrophy,BMD).All subjects were imaged T 1WI-Dixon,multiechoic M-Dixon quant and T 2-mapping of the thigh muscles,and the FF values and T 2 values of 14 muscles of the right thigh(gluteus maximus,tensor fascia lata,lateral femoris,middle femoris,medial femoris,rectus femoris,sartorius,adductor longus,adductor major,thin femoris,semimembranous muscle,semitendon muscle,biceps femoris longhead,and biceps femoris brevity)were measured.The Mann-Whitney U test was used to compare the differences in FF value,T2 value,average FF value and T2 value of 14 muscles in DMD group and BMD group,and plotted the working characteristics(ROC)curves of the average FF value and T2 value of 14 muscles,calculated the area under the curve(AUC),and evaluated the differential diagnostic efficacy of the curve for DMD and BMD respectively.Results:①In the DMD group,gluteus maximus FF values were the highest,followed by adductor major,quadriceps,and the lowest in the gracilis,sartorius and adductor longus.In the BMD group,the FF value of gluteus maximus muscle was the highest,followed by the medial femoral muscle,and the lowest was the gracilis and adductor longus.②In the DMD group,the gluteus maximus T2 value was the highest,followed by adductor major and quadriceps,and the lighigis and semitendon muscle were the lowest;In the BMD group,the gluteus maximus muscle T2 value was the highest,followed by the medial femoral muscle,and the lowest.③Except for the sartorius muscle and adductor longus muscle(P>0.05),the FF values of the other 12 muscles and the average FF values of the 14 muscles in the DMD group were higher than those in the BMD group,and the difference was statistically significant(P<0.05).The T2 values of each muscle and the average T2 value of 14 muscles in the DMD group were higher than those in the BMD group,and the differences were statistically significant(P<0.05).The AUCs of the mean FF value and T2 value of 14 muscles were 0.709(0.591~0.828)and 0.924(0.857~0.992),respectively,and the average T2 value of 14 muscles was the most effective,with the best cut-off value of 41.55ms,sensitivity of 86%,and specificity of 88%.Conclusion:Both multiecho M-Dixon quant and T 2-mapping technology can effectively identify children with dystrophin disease,and muscle T2 value measurement based on T 2-mapping technology has higher diagnostic performance and has certain clinical significance.