【摘要】 目的应用磁共振成像（magnetic resonance imaging,MRI）和磁共振波谱（magnetic resonance spectroscopy,MRS）技术对职业性慢性铅中毒患者脑海马体积和脑代谢物含量进行检查,探讨职业性慢性铅中毒患者的海马容量和相关区域脑代谢物改变与记忆力改变的关系。方法以8例职业性铅中毒工人为研究对象（工龄6³7年）,按性别、年龄因素匹配健康对照者8例,利用MRS技术检测其相关脑区N-乙酰天门冬氨酸（N-acetyl aspartate,NAA）、脂质（lipid,Lip）、胆碱（choline,Cho）、谷氨酰胺和谷氨酸复合物（glutamate and glutamine,Glx）、乳酸（lactate,Lac）和肌醇（myoinositol,MI）水平,分别与肌酸和磷酸肌酸（creatine and phosphocreatine,Cr）水平相比并以此代表该代谢物的水平。通过三维T₁加权MRI测量海马体积。利用韦氏记忆量表测试记忆能力。结果慢性铅中毒组额叶、基底节和海马的NAA/Cr比值,基底节和海马的MI/Cr比值,以及海马体积显著区别于对照组（P<0.05）。结论职业性慢性铅暴露可以引起脑结构和代谢的改变,这可能是记忆力损伤的原因。更多还原

【Abstract】 Objective We examined typical changes in hippocampus volume and metabolite ratios in the workers chronically exposed to lead,and compared with those of control individuals,using magnetic resonance imaging（MRI） and proton magnetic resonance spectroscopy（1^HMRS）,then,investigated whether an abnormality in brain capacity or metabolism associated with memory changes.Methods The subjects included 8 workers chronically exposed to lead（job years 6- 37） and 8 gender age and matched healthy people,MRS was used in the related region of the brain to detect N-acetyl aspartate（NAA）,lipid（Lip）,choline（Cho）,glutamate and glutamine（Glx）,Lactate（Lac） and myoinositol（mI） levels,and each item was expressed respectively as a ratio to creatine and phosphocreatine（Cr）.We also assessed the hippocampus volume on 3D T₁weighted MRI.Neurobehavioral tests were also performed to define memory status.Results NAA/Cr ratio in the frontal lobe,basal ganglia and hippocampus,MI/Cr ratio in basal ganglia and hippocampus,and the hippOcampal volume were significantly different to those of control subjects（P < 0.05）.For the workers conformed lead poisoned,the blood lead concentration was significantly correlated with Ml/Cr ratio,NAA/Cr ratio in the hippocampus as well as hippocampus volume（P <0.05）.Conclusion Occupational exposure to lead may cause subtle structural and functional alteration in human brains,which may be one reason of memory lost.更多还原