屏气fMRI评价2型糖尿病患者脑血管反应能力

目的 利用fMRI结合屏气方法评价2型糖尿病(T2DM)患者的脑血管反应能力(CVR)。方法 对25例T2DM患者(T2DM组)和25名健康志愿者(对照组)进行屏气条件下的fMRI试验。采用SPM8进行数据处理和统计分析,组内分析采用单样本t检验,组间分析采用双样本t检验。将存在CVR组间差异的脑区建立为ROI,提取所有受试者的BOLD信号变化百分比(PSC),比较组间ROI内平均PSC的差异,并将T2DM组的PSC与临床行为学、心理学及血糖控制水平进行相关分析。结果 无并发症的T2DM患者与对照组的CVR分布均以灰质为主(P<0.05, FWE校正),T2DM组双侧前额叶内侧面及背外侧面的CVR明显高于对照组(P<0.01,AlphaSim校正),该区域的PSC与临床行为学、心理学和血糖控制水平之间无相关性。结论 屏气fMRI可用于评价CVR,无明显并发症的T2DM患者双侧前额叶的CVR升高,可能处于代偿期,有发生记忆和执行功能障碍的风险。

Breath holding fMRI evaluation of cerebrovascular reactivity in patients with type 2 diabetes mellitus

Objective To investigate cerebrovascular reactivity to carbon dioxide (CO2R) in type 2 diabetes mellitus (T2DM) patients using breath holding fMRI (BH-fMRI). Methods Twenty-five T2DM patients (T2DM group) and 25 control subjects (control group) were enrolled and underwent BH-fMRI. SPM8 based on MatLab were used for fMRI data processing and statistical analysis. Differences between intergroup and the two groups were analyzed using one sample t-test and two sample t-test respectively. The percent signal change (PSC) of BOLD was extracted from ROI which built based on intergroup comparison. The relationship between the PSC of the ROI and the indices of behavior, psychology and metabolic control was tested by correlation analysis. Results Both T2DM and control groups exhibited signal changes in gray matter during the breath holding test (P<0.05, FWE corrected). CVR of bilateral prefrontal lobe, mainly in anteromedial part of superior frontal gyrus and dorsolateral part of superior frontal gyrus, were higher in T2DM group than those in control group (P<0.01, AlphaSim corrected). There were no relationship between the PSC of this ROI and the data of clinical and laboratory examinations. Conclusion BH-fMRI offers method for assessing CVR. The CVR of bilateral prefrontal lobe, mainly in anteromedial part of superior frontal gyrus and dorsolateral part of superior frontal gyrus, is higher in T2DM group, which may indicate that patients with T2DM are prone to disfunction of memory and execution.