阻塞性睡眠呼吸暂停综合征白质损害特点与记忆功能的关系

Correlation between white matter lesion and memory impairment in patients with obstructive sleep apnea syndrome

目的用磁共振弥散张量成像(DTI)方法研究阻塞性睡眠呼吸暂停综合征(OSAS)患者脑白质损害的特点,并分析其与记忆相关性。方法对10例男性OSAS患者和10名年龄及文化程度相当的男性健康志愿者,测试修订韦氏记忆量表(WMS)得分,分别行脑部DTI扫描。选择双侧额叶白质、前部扣带回、前部扣带、半卵圆中心、前角周围白质、后角周围白质、尾状核头部、丘脑、海马旁回以及胼胝体膝部、胼胝体干、胼胝体压部作为兴趣区(ROI),分别测量部分各向异性分数值(FA)、平均扩散系数(ADC)并进行统计学分析,并与WMS得分进行相关性分析。结果OSAS组右侧额叶白质、胼胝体压部、左侧前部扣带回、右侧前部扣带回、左侧前部扣带、右侧前部扣带、左侧半卵圆中心、左侧前角周围白质、左侧后角周围白质、右侧后角周围白质、左侧海马旁回、右侧海马旁回的FA值分别为:0.444±0.025、0.776±0.028、0.154±0.021、0.152±0.017、0.372±0.022、0.351±0.029、0.501±0.029、0.434±0.045、0.338±0.029、0.360±0.022、0.167±0.027、0.177±0.023,与健康对照组相比显著下降(P<0.05),其中右侧额叶白质与联想、理解分值、左侧半卵圆中心与再生分值呈正相关关系(r值分别为0.679、0.642、0.671,P<0.05),而左侧额叶白质、右侧半卵圆中心、右侧前角周围白质、尾状核头部、丘脑、胼胝体膝部、胼胝体干的FA值与对照组相比无显著差异(P>0.05)。右侧额叶白质、胼胝体干、胼胝体压部、左侧前部扣带回、右侧前部扣带回、右侧前部扣带、左侧半卵圆中心、左侧前角周围白质的ADC值分别为:8.589±0.264、8.197±0.253、8.218±0.194、12.151±0.454、12.113±0.524、8.954±0.177、7.333±0.220、9.186±0.465×e-10mm2/s,与健康对照组相比显著升高(P<0.05),与WMS分值无相关关系;而左侧额叶白质、左侧前部扣带、右侧半卵圆中心、右侧前角周围白质、双侧后角周围白质、尾状核头部、丘脑、海马旁回、胼胝体膝部的ADC值与对照组相比无显著差异(P>0.05)。结论(1)OSAS病人同时存在白质和灰质损害;(2)OSAS病人记忆障碍可能是皮质、白质共同受损的结果。

Objective To investigate the nature of white matter lession and correlation to memory impairment in patients with obstructive sleep apnea syndrome （OSAS） by diffusion tensor imaging （DTI）. Methods We conducted a cross-sectional study of 20 middle-aged male people （10 with OSAS and 10 healthy controls） group-matched by age, educational level, and socioeconomic status. DTI was performed on those people with OSAS and on matched controls. Fractional anisotropy （FA） and average diffusion coefficient （ADC） values were measured respectively in bilateral white matter of the frontal lobe, anterior cingnlate gyrus, anterior cingnlum, etc. At the same time, WMS values were detected respectively. Results Relative to controls, patients with OSAS had a lower FA in the white matter of right frontal lobe （0.444±0.025）, splenium of corpus callosum （0.776±0.028）, left anterior cingulate gyrus （0.154±0.021）, right anterior cingulate gyms （0.152±0.017）, left anterior cingulum （0.372±0.022）, right anterior cingnlurn （0.351±0.029）, left centrum semiovale （0.501 ±0.029）, peripheric white matter of left anterior angle （0.242±0.031）, peripheric white matter of left posterior angle （0.338±0.029）, peripheric white matter of right ＇posterior angle （0.360±0.022）, left parahippocampal gyrus （0.167±0.027）, right parahippocarnpal gyrus （0.177±0.023）. Besides, FA values of OSAS patients in the white matter of right frontal lobe and left centrum semiovale were strongly positively correlated with WMS values. While in comparison with that of healthy controls, ADC of OSAS patients was significantly higher in the white matter of right frontal lobe （8.589±0.264xe^-10 mm^2/s）, trunk of corpus callosum （8.197±0.253xe^-10 mm^2/s）, splenium of corpus callosum （8.218±0.194xe^-10 min^2/s）, left anterior cingulate gyrus （12.151±0.454xe^-10 minE/s）, right anterior cingulate gyrus （12.113±0.524xe^-10 mm^2/s）, right anterior cingulum （8.954±0.177xe^-10 mm^2/s）,left centrum semiovale （7.333±0.220xe^-10 mm^2/s） and peripheric white matter of left anterior angle （9.186±0.465xe^-10 mm^2/s）.Conclusions This study indicated that white matter and gray matter was both remarkably damaged in OSAS patients, which could contribute to memory impairment.