健康成人直肠刺激脑fMRI研究

目的:运用功能磁共振成像(f MRI)探讨健康成年人直肠内气囊扩张刺激后脑内活动区的分布和状况。方法:11例健康志愿者,以不同气体量进行直肠内气囊扩张刺激,以静息-刺激为一个周期,得到脑f MRI图像并将其与T1WI进行图像融合,测量脑内活动区的面积和信号强度并进行统计学分析。结果:直肠内气囊扩张刺激明显激活扣带回前皮层(ACC,11/11),脑岛皮层(IC,11/11),前额叶皮层(PFC,11/11)和丘脑(THAL,9/11)。在注气量达到90ml和120ml时,均以ACC内活动区面积最大,以PFC和ACC内活动区MRI信号强度变化幅度最大。结论:健康成年人直肠内气囊扩张刺激,脑内激活区主要位于ACC和PFC,其次是IC和THAL,提示这些区域是脑内内脏感觉中枢的组成部分。f MRI能够反映大脑中枢的活动。

Brain fMRI Study in Chinese Volunteers During Rectal Balloon-distention

Objective:To study the regional brain activation in healthy volunteers using rectal balloon distention for stimulation.Methods:The study was performed in 11 healthy volunteers during rectal balloon distention with various volume of air for stimulation.Taking rest,stimulate as one cycle,brain images were obtained and were integrated with T_1WI anatomic images.The area and signal intensity of brain activated regions were measured and analyzed statistically.Results: Taking rectal distention as stimulation increased the activity of anterior cingulate cortex (ACC,11/11),insular cortex (IC,11/11),prefrontal cortex (PFC,11/11) and thalamus (THAL,9/11).The area of activation region at ACC is the biggest when 90ml and 120ml air was injected into the rectal balloon.Changes of amplitude of MRI signal intensity was the biggest at the activation region at ACC and PFC with various degree of rectal distension.Conclusion:This study indicates that using rectal balloon distension,fMRI can reflect the brain activation in healthy volunteers.The central activated area mainly located at ACC and PFC,IC and THAL placed secondly.It suggests that these areas are part of the visceral sensation center of brain.