Pohlmeier R, Buchner H, Knoll G, Rienäcker A, Beckmann R, Pesch J
Department of Neurology, RWTH Aachen, FRG.
Brain Topogr. 1997 Spring;9(3):157-62. doi: 10.1007/BF01190384.
The electric conductivities of different tissues are important parameters of the head model and their precise knowledge appears to be a prerequisite for the localization of electric sources within the brain. To estimate the error in source localization due to errors in assumed conductivity values, parameter variations on skull conductivities are examined. The skull conductivity was varied in a wide range and, in a second part of this paper, the effect of a nonhomogeneous skull conductivity was examined. An error in conductivity of lower than 20% appears to be acceptable for fine finite element head models with average discretization errors down to 3 mm. Nonhomogeneous skull conductivities, e.g., sutures, yield important mislocalizations especially in the vincinty of electrodes and should be modeled.
不同组织的电导率是头部模型的重要参数，准确了解这些参数似乎是在脑内定位电源的先决条件。为了估计由于假设电导率值的误差而导致的源定位误差，研究了颅骨电导率的参数变化。颅骨电导率在很宽的范围内变化，并且在本文的第二部分中，研究了非均匀颅骨电导率的影响。对于平均离散化误差低至3mm的精细有限元头部模型，电导率低于20%的误差似乎是可以接受的。非均匀颅骨电导率，例如缝合线，会导致重要的定位错误，尤其是在电极附近，因此应该进行建模。
