再生障碍性贫血患者的腰椎骨髓MRI表现与氢质子磁共振波谱特征

Magnetic resonance imaging manifestations and ^(1)H-magnetic resonancespectroscopy features of lumbar bone marrow in patients with aplastic anemia

目的探讨再生障碍性贫血(AA)患者的腰椎骨髓MRI表现和氢质子磁共振波谱((1)^H-MRS)特征。方法选取21例AA患者及22例健康志愿者(正常对照组),均行腰椎MRI及(1)^H-MRS检查。总结所有研究对象腰椎骨髓MRI表现及波谱信号。分析AA患者非造血岛骨髓和正常对照组骨髓脂肪分数的影响因素。结果21例AA患者中,腰椎MRI表现为弥漫型3例、灶型4例、混杂型14例。AA患者的非造血岛骨髓(1)^H-MRS特征为脂峰高耸、水峰低平或消失,造血岛骨髓(1)^H-MRS特征为水峰高耸、脂峰低平或消失;正常对照组(1)^H-MRS特征为水峰稍高于(<40岁)或稍低于(>40岁)脂峰。AA患者非造血岛骨髓、正常对照组患者骨髓、AA患者造血岛骨髓的脂肪分数依次降低(均P<0.05)。多重线性回归分析提示AA患者非造血岛骨髓脂肪分数受水峰峰下面积的影响大于脂肪峰的峰下面积,而正常对照组骨髓脂肪分数受脂肪峰峰下面积的影响大于水峰的峰下面积(P<0.05)。结论MRI可以作为评价AA腰椎骨髓类型和状态的无创性检查方法,(1)^H-MRS可在常规MRI基础上无创性评估腰椎骨髓水脂成分,两者可弥补局部骨髓穿刺活检的不足。

Objective To investigate MRI manifestations and (1)^H-magnetic resonance spectroscopy((1)^H-MRS)features of lumbar bone marrow in patients with aplastic anemia(AA).Methods Twenty-one AA patients and 22 healthy volunteers(normal control group)were enrolled and underwent lumbar MRI and (1)^H-MRS examinations.The MRI manifestations and spectroscopic signals of lumbar bone marrow of all subjects were summarized.The factors influencing non-hematopoietic island bone marrow of AA patients and bone marrow fat fraction of the normal control group were analyzed.Results Of 21 AA cases,there were three cases of diffuse type,four of focal type and 14 of mixed type on lumbar MRI.Non-hematopoietic island bone marrow of AA patients was featured by high peak lipid,and low-flat or disappeared peak water on (1)^H-MRS,while hematopoietic island bone marrow was featured by high peak water,low-flat or disappeared peak lipid on (1)^H-MRS;the normal control group was characterized by peak water slightly higher(<40 years)or slightly lower than(>40 years)peak lipid on (1)^H-MRS.Fat fraction decreased in the order of non-hematopoietic island bone marrow of AA patients,bone marrow of patients in the normal control group and hematopoietic island bone marrow of AA patients(all P<0.05).Multiple linear regression analysis indicated that fat fraction of non-hematopoietic island bone marrow of AA patients was affected more by area under peak water than area under peak lipid,whereas fat fraction of bone marrow of the normal control group was affected more by area under peak lipid than by area under peak water(P<0.05).Conclusion MRI can serve as the noninvasive examination method assessing the type and status of lumbar bone marrow of AA,(1)^H-MRS can noninvasively evaluate water-lipid composition of lumbar bone marrow based on routine MRI,the two methods can make up the deficiencies of local bone marrow aspiration and biopsy.