三道导纳胃动图的原理、方法与意义

3-Channel Admittance Motorogastrography: the Principle, Method and Significance

在机体躯干两侧导入高频微弱恒定电流时,由胃投影部位皮肤电极可测得与胃运动相关的阻抗和导纳变化。本文建立一种导纳法检测胃运动的数理模型。生物物理分析表明,在腹壁两个检测电极间距(L)不变,且相应腹部组织及胃内容物电阻率(ρ1)稳定的情况下,△V=ρ1L2f穴△Y雪。即腹壁电极测得的导纳变化的函数f穴△Y雪与电极相关部位胃体积改变△V呈正比。依据本原理成功研制三道导纳胃动图仪熏可非侵入性检测与胃运动相关的导纳变化。记录的波形作频谱分析,报告胃运动的频率与强度,并判断胃蠕动波的移行方向与速度。该原理及由此研制的胃动图仪可在消化道生理、病理生理、药理及临床应用上发挥重要作用。

When high frequency feeble constant current is imported to body trunk from sides, the change of impedance and admittance correlative with stomach's motility can be measured through the electrodes put on the corresponding skin area of stomach's projection part. This article has established a mathematic-physics model in order to measure stomach motility. Biophysics analysis shows that under the condition that the distance between 2 detecting electrodes(L) do not change and that the corresponding resistivity of abdominal tissue and gastric contents(ρ1)is steady, then△V=ρ■L2f(△Y), that is, the function of the change of admittance f(△Y)measured through the electrodes on the surface of abdominal wall and the change of stomach volume △V related with the position of electrodes are in positive correlation. According to this theory, we developed an admittance testing system for 3-channel stomach motility, which can non-intrusively detect the change of admittance correlative with stomach motility. The waveform recorded can be analyzed by power spectrum analysis, and the equipment can get data of the frequency and intensity of stomach motility, and estimates the migrating direction and speed of stomach peristalsis. This theory and the motorogastrogram equipment developed according to this theory can play an important role in physiology, pathophysiology, pharmacology and clinic application of the area of alimentary tract.