正常中年人海马磁共振扩散张量成像相关参数研究

目的探讨正常中年人海马不同年龄组、不同部位表观扩散系数(apparent diffusion coefficient,ADC)、各向异性分数(fractional anisotropy,FA)值的变化规律,为临床早期诊断及治疗海马相关性疾病提供参考依据。材料与方法从社区健康志愿者中选取符合标准者276名,按年龄分3组,A组:壮实期(41~48岁)90名,B组:稳健期(49~55岁)93名,C组:调整期(56~65岁)93名,行常规颅脑MR平扫、双侧海马扩散张量成像(diffusion tensor imaging,DTI)扫描,测量双侧海马头、体、尾部ADC、FA值,分析不同性别间、左右侧别间、各年龄组间及同年龄组不同部位间各参数的差异及各参数与年龄的相关性。结果 ADC、FA值在男女之间、左右侧别间差异无统计学意义(P0.05);各年龄组间相同部位各参数差异有统计学意义(P0.05),ADC值A、B组均低于C组(P0.05),FA值A、B组均高于C组(P0.05);FA值在同年龄组不同部位间差异有统计学意义(P0.05),FA值在A、B、C组海马头部高于体、尾部(P0.05)。FA值与年龄呈负相关(r=-0.813,P0.05);ADC值与年龄呈正相关(r=0.113,P0.05)。结论 DTI能反映正常中年人海马不同部位微环境的变化,为早期临床诊断及治疗海马相关性疾病提供参考依据。

Study of relevant parameters of diffusion tensor imaging in the hippocampus of normal middle-aged group

AbstractObjective:To discuss the change of the brain metabolites on the bilateral hippocampus of different age groups and different parts in normal Chinese middle-aged group by using Diffusion Tensor Imaging (DTI), to provide the reference for early clinical diagnosis and treatment of hippocampal-related diseases.Materials and Methods: From community healthy volunteers, we selected 276 according to the standards, who were divided into three groups according to age, A group: prime period, 41 to 48 years, 90 cases; B group: steady period, 49 to 55 years, 93 cases; C group: adjustment period, 56 to 65 years, 93 cases. All subjects underwent routine conventional MRI and bilateral hippocampal DTI examination. The parameters ADC, FA values were measured. To analyse the differences of the parameters between different genders, sides, groups and parts, and discuss the correlation between parameters and age.Results:There was no statistically signiifcant difference of ADC and FA values of the hippocampus between different sides and genders (P>0.05). The values had statistically signiifcant difference among groups (P<0.05). The ADC value in group A and B was lower than group C (P<0.05), the FA value in group A and B was higher than group C (P<0.05), the FA value had statistically signiifcant difference in the different parts of hippocampal (P<0.05), the FA value in A, B and C group on hippocampal head was higher than on body and tail. The FA values were negatively correlated with age (r=-0.813,P<0.05), the ADC values were positively correlated with age (r=0.113, P<0.05).Conclusion:DTI can help to understand the changes of microenvironment of the hippocampal in normal Chinese middle-aged people, to provide clinical basis for early diagnosis and treatment of the diseases associated with hippocampus.