Influence of changing peripheral geometry on electrical impedance tomography measurements
Influence of changing peripheral geometry on electrical impedance tomography measurements
复制标题
改变外围几何形状对电阻抗断层扫描测量的影响
DOI：
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发表时间：
1996
影响因子：
3.2
通讯作者：
M. Osypka
中科院分区：
文献类型：
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作者：
E. Gersing;B. Hofmann;M. Osypka
关于电阻抗断层成像（EIT）中的动态成像，理论推导和实际测量表明，在参考测量和主测量过程中，有必要保持物体横截面的周边几何形状处于恒定的研究之下（a（WEBSTER 1990 a，B HEIMBACK，1990）。然而，在医疗检查程序中一般不能提供这一必要条件。这种困境有两个原因;首先，在测量过程中几乎不可能保持患者不动，因为这只有麻醉患者或姿势稳定的患者才有可能。其次，外围几何形状在检查期间容易受到由于呼吸引起的变化的影响，例如（ADLER等人，1994年）。这导致了这样的问题，即所生成的图像在多大程度上一方面由所研究的横截面中的变化的电阻率分布引起，或者另一方面由外围几何形状的变化（例如，在呼吸期间）引起。在电极5和13（图1）附近的弹性罐的壳体上施加相应的径向力。椭圆的轴线dl位于所施加的力的方向上;轴线d2垂直于dl。da中Dx的相对变化为：
WITH REGARD to dynamic imaging in electrical impedance tomography (EIT), theoretical deduction and practical measurements show that it is necessary to keep the peripheral geometry of the cross-section of the object under constant investigation during the reference and main measurements (a (WEBSTER 1990a, b HEIMBACK, 1990). This necessary condition, however, cannot generally be provided for in medical examination procedures. There are two reasons for this predicament; first it is almost impossible to keep the patient immobile during the measurement procedure as this is only possible with anaesthetised patients or patients with stabilised posture. Secondly, the peripheral geometry is susceptible to changes during the examination due to respiration, for example (ADLER et al., 1994). This leads to the question of the extent to which the generated image is caused by the changed resistivity distribution in the cross-section under investigation on the one hand, or by the changes of the peripheral geometry on the other hand, e.g. during respiration. corresponding radial force on the shell of the elastic tank near electrodes 5 and 13 (Fig. 1). Axis dl of the ellipse is situated in the direction of the force applied; axis d2 is perpendicular to dl. The relative changes Dx in da are