功能性消化不良患者水负荷试验时大脑感知作用的fMRI研究

A fMRI Study on Brain Perception Response during Water Load Test in Patients with Functional Dyspepsia

背景:应用功能性核磁共振成像(fMRI)可提示内脏感觉转导作用和内脏高敏感的中枢机制。目前水负荷试验(WLT)致中枢反应的fMRI研究尚少见。目的:研究功能性消化不良(FD)患者WLT时大脑皮质的信息反应特点,探讨其内脏高敏感的中枢机制。方法:纳入符合罗马Ⅲ标准的11例餐后不适综合征(PDS)、13例上腹痛综合征(EPS)患者以及12名对照者。受试者行WLT时接受fMRI检查。结果:PDS和EPS组胃初次饱足阈值、最大饱足阈值均显著低于对照者(P<0.05)。三组激活脑区大部分集中于双侧大脑半球的前扣带回、颞叶、额叶、岛叶(左侧为主)、楔叶(左侧为主)、丘脑、小脑。PDS组胃初次饱足时颞叶、小脑以及最大饱足时小脑、岛叶的fMRI最大信号变化幅度均显著高于对照者(P<0.05);EPS组胃初次饱足时以及最大饱足时前扣带回、枕叶均显著高于对照者(P<0.05);除最大饱足时枕叶外,两个FD亚组之间均无明显差异(P>0.05)。结论:WLT时FD患者大脑感知作用可能与健康对照者相似,中枢在边缘系统(主要为岛叶、前扣带回)以及颞叶、小脑、枕叶等脑区的加工、处理或调节存在异常,导致内脏敏感性增高:而FD亚型之间无明显差异。

Background：Visceral sensation transmission and central mechanism of visceral hypersensitivity could be examined by functional magnetic resonance imaging（fMRI）,however,few fMRI studies on central response induced by water load test（WLT） have been reported.Aims：To study the characteristics of cerebral cortex response during WLT in patients with functional dyspepsia（FD）,and to investigate the central mechanism of visceral hypersensitivity.Methods：Eleven patients with postprandial distress syndrome（PDS） and 13 patients with epigastric pain syndrome（EPS） diagnosed according to Rome HI criteria were enrolled,and 12 healthy volunteers were served as controls.WLT and fMRI were performed.Results：The initial and maximal gastric satiety thresholds of WLT were significantly lower in PDS and EPS groups than in controls（P0.05）.Activated regions were mostly at anterior cingulate cortex,temporal lobe,frontal lobe, insular lobe（mainly the left）,cuneus（mainly the left）,thalamus and cerebellum.fMRI maximum signal amplitude changes of temporal lobe,cerebellum during initial gastric satiety and of cerebellum,insular lobe during maximal gastric satiety in PDS were significandy higher than those in controls（P0.05）;fMRI maximum signal amplitude changes of anterior cingulate cortex,occipital lobe during both initial gastric satiety and maximal gastric satiety in EPS were significantly higher than those in controls（P0.05）.No statistically significant differences were found between the two FD subgroups except for the occipital lobe during maximal gastric satiety（P0.05）.Conclusions：The brain perception response of FD patients during WLT may be similar with healthy controls,but the processing,managing or regulating activities in limbic system（mainly insular lobe,anterior cingulate cortex） and temporal lobe,cerebellum,occipital lobe are abnormal,resulting in visceral hypersensitivity.However,no significant difference was found between subtypes of FD.