多回波Dixon与HISTO在儿童急性淋巴细胞白血病中应用价值初探

Preliminary Study on the Application Value of Modified Multiecho Dixon and HISTO in Children with Acute Lymphoblastic Leukemia

目的初步探讨多回波Dixon与高速多回波T_(2)校正(HISTO)磁共振氢质子波谱成像两种定量脂肪技术在儿童急性淋巴细胞白血病(ALL)中的应用价值,并对两种技术所得骨髓脂肪分数(FF)的相关性及一致性进行评价。方法搜集经骨髓穿刺活检证实的初诊ALL患儿33例,年龄5~15岁,平均(8.09±2.73)岁,男21例,女12例;对照组为33例年龄相匹配的同龄正常儿童志愿者,年龄5~15岁,平均(7.67±2.86)岁,男18例,女15例。所有研究对象在Siemens Prisma 3.0T MRI完成扫描后将图像传至Syngo.via工作站,分别于腰椎3(L_(3))、腰椎4(L_(4))椎体正中层面、双侧髂骨、双侧股骨小转子下1 cm处髓腔内选取感兴趣区(ROI),每个ROI测量3次,取其平均值。结果33例ALL组患者分别应用多回波Dixon、HISTO在L_(3)、L_(4)、髂骨、股骨上段水平所测得骨髓FF均明显低于正常对照组,两组之间差异具有统计学意义,应用多回波Dixon两组对比t值依次分别为:24.677、25.057、39.686、37.244,所有P值均<0.01;应用HISTO两组对比t值依次分别为:23.911、24.573、28.770、27.060,P值均<0.01。对照组两种定量脂肪技术在L_(3)与髂骨、L_(3)与股骨上段、L_(4)与髂骨、L_(4)与股骨上段、髂骨与股骨上段之间测得的骨髓FF差异具有统计学意义,所有P<0.05;ALL组两种定量脂肪技术在各部位之间测得的骨髓FF差异无统计学意义,所有P值>0.05。对照组分别应用Dixon、HISTO在L_(3)、L_(4)、髂骨、股骨上段水平所测得骨髓FF之间对比差异无统计学意义,t值依次分别为:1.730、1.807、1.951、1.908,P值均>0.05;ALL组应用Dixon、HISTO两种技术在各部位测得的骨髓FF对比差异亦无统计学意义,t值依次分别为:1.940、1.457、-0.611、1.491,P值均>0.05。对照组采用Dixon与HISTO两种技术所得骨髓FF、ALL组采用Dixon与HISTO两种技术所得骨髓FF进行相关性分析显示分别存在显著相关性,r值分别为0.828、0.774,P值均<0.001。在Bland-Altman分析中,两种定量脂肪技术在对照组Dixon与HISTO、ALL组Dixon与HISTO之间所得的骨髓FF均显示两种方法具有较好的一致性。结论多回波Dixon及HISTO两种定量脂肪测量技术对ALL患者的骨髓受侵具有一定的影像学诊断价值,两种检查技术具有较好的相关性与一致性,可作为ALL患者的临床辅助检查手段。

Objective To explore the value of two quantitative fat techniques by application modified multiecho dixon and HISTO in children with acute lymphoblastic leukemia(ALL),and to evaluate the correlation and consistency of bone marrow fat fraction obtained by the two techniques.Methods 33 cases primary ALL children were confirmed by bone marrow aspiration biopsy in our hospital were collected,aged 5-15 years,meanage 8.09±2.73,21 males and 12 females;the control group consisted of 33 age-matched volunteers of normal children,aged 5-15 years,meanage 7.67±2.86,18 males and 15 females.All the subjects were scanned on Siemens Prisma 3.0 T MRI.After scanning,the images were transmitted to the syngo.via workstation,ROIs were selected in the medullary cavity at the median level of L_(3) and L_(4) vertebrae,bilateral iliac bone,and 1 cm below trochanter of bilateral femur,each ROI was measured three times and the average value was taken.Results Bone marrow FF measured at the level of L_(3),L_(4),iliac bone,and upper femur in 33 patients of ALL group were significantly lower than those in the normal control group by using multi-echo Dixon and HISTO,and there were statistical differences between the two groups,Among them,the comparison t values of the two groups using multi-echo Dixon were 24.677,25.057,39.686,37.244,all P<0.01;the t values of the two groups using HISTO were 23.911,24.573,28.770,27.060,all P<0.01.The bone marrow FF between of L_(3) and the ilium,L_(3) and the upper femur,L_(4) and the ilium,L_(4) and the upper femur,and the ilium and the upper femur that there are statistical differences by using two quantitative fat techniques in the control group,all P<0.05;There was no statistical difference of bone marrow FF between the two quantitative fat techniques in the ALL group,all P>0.05.There was no statistical difference in the comparison of bone marrow FF measured by Dixon and HISTO at the level of L_(3),L_(4),iliac,and upper femur in the control group,the t values were 1.730,1.807,1.951,1.908,all P>0.05;The comparison of bone marrow FF measured by Dixon and HISTO in the ALL group at each site was not statistically difference,the t values were 1.940,1.457,-0.611,1.491,all P>0.05.Correlation analysis of bone marrow FF obtained by Dixon and HISTO techniques in the control group and bone marrow FF obtained by Dixon and HISTO techniques in the ALL group showed significant correlations,respectively,the R values were 0.828 and 0.774,and both P values<0.001.In the Bland Altman analysis,the bone marrow FF obtained by the two quantitative fat techniques between Dixon and HISTO in the control group and ALL group showed that the two methods have good consistency.Conclusion Multiecho Dixon and HISTO two quantitative fat techniques have certain imaging diagnostic value for bone marrow invasion in ALL patients.The two examination techniques have better correlation and consistency,and can be used as clinical auxiliary examination methods for ALL patients.