【摘要】 目的 :探讨磁共振成像 (MRI)与1 H磁共振波谱 (1 HMRS)在定量研究人脑的正常生理生化进程以及正常老年脑与老年性脑疾病的鉴别等方面的应用价值。方法 :选择 180例经临床及MRI检查并除外精神神经疾患病史的健康志愿者。年龄 18～ 80岁。按年龄分为六组 ,每组 30例。同时选择 6 0例进行1 HMRS检查 ,每组 10例 ,1 HMRS采用定点分辨波谱序列 ,测定N -乙酰基天门冬氨酸 (NAA)、胆碱复合物 (CHO)、肌酸复合物 (CR)、肌醇 (MI)、乳酸 (LAC)、谷氨酸及谷氨酰胺 (Glu -n)等。结果 :(1) 180例正常成人在同一年龄组以深部灰质核团T2 值为最低 ;不同年龄组同一部位灰质的比较中 ,T1 值先降后升 ,深部灰质核团T2 值随年龄的增长而下降。 (2 ) 6 0例正常成人1 HMRS中 ,波幅从高至低的顺序为NAA、CR、CHO、MI、Glu -n。同一年龄组1 HMRS波形及波幅排列次序无显著变化 ;不同年龄组同一部位所获取的1 HMRS波形与波幅略有不同。正常成人脑灰质中NAA CR及Glu -n CR均值随年龄的增长其比值逐渐呈上升趋势 ;MI CR随年龄的增长而下降 ,CHO CR先下降后上升。同一年龄组不同部位从前至后NAA CR及MI CR的比值逐渐下降 ;CHO CR以枕叶为最高 ;而Glu -n CR无一定规律。灰质T1 弛豫时间及部分代谢物比值与年龄具有相关性。结论 :MRI?更多还原

【Abstract】 Objective:To evaluate magnetic resonance imaging(MRI) and 1 H magnetic resonance spectroscopy( 1HMRS)in the study of normal biochemical process of the brain as well as differentiation of normal senile brain from cerebral diseases related to senility.Methods:180 cases of healthy adults were selected to perform MR examination,in which,none of the subjects had the history of neurological and psychotic diseases according to MRI and clinical results.Meanwhile,60 healthy subjects were selected to perform 1 HMRS examination.The ages ranged from 18 to 80 years.They were divided into six age groups purposely.Point resolved spectroscopy sequence was required for 1 HMRS.The metabolites in the spectra included:N-acetylaspartate(NAA),choline compounds(CHO),creatine compounds(CR),myo-inosito(MI),glutamate and glutamine(Glu-n).Results:(1)In 180 cases of MRI,T 2 relation time was lowest in the deep gray matter in the same age group;T 1relation time was in low-high order,while T 2 relation time was decreased with the increase of age in the different age group.(2)The amplitudes in high-to-low order were as follows in 60 cases of 1 HMRS:NAA、CR、CHO、MI、Glu-n.No prominent difference of shape and peak arrangement was seen at the different ipsilateral site in the same age groups;while slight difference at the same site in the different age groups was present.The ratio of NAA/Cr and Glu-n CR was higher in senile age group;while that of MI/Cr was lower.The ratio of CHO/CR was in low-to high order with the difference of age.The ratio of NAA/CR and MI/CR was gradually lower from anterior to posterior part of the brain;the ratio of CHO/CR was highest in occipital cortex however,no definite changing rule was observed in the ration of Glu-n/CR.Correlation of T 1 relation time and partial metabolite ratio with age was present in gray matter.Conclusion:Quantitative study of MRI and 1 HMRS is essential for determination of normal myelinization and neuronal integrity and age-related biochemical changes in the brain.更多还原