An evaluation of dipole reconstruction accuracy with spherical and realistic head models in MEG
An evaluation of dipole reconstruction accuracy with spherical and realistic head models in MEG
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DOI：
10.1016/s1388-2457(99)00174-1
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发表时间：
1999-12-01
影响因子：
4.7
通讯作者：
Pernier, J
中科院分区：
文献类型：
--
作者：
Crouzeix, A;Yvert, B;Pernier, J
本文用边界元法（BEM）和一个非常精细的三层真实感头部模型，求解了大约2000个偶极子在脑表面的脑磁图正演问题。对于每个偶极子，球模型，一层真实感边界元模型和粗糙的三层真实感边界元模型，被用来重建偶极子。结果发现，由使用头部的球形模型引起的定位偏差从头部上部的2.5 mm增加到下部的12 mm，平均。还发现，对于相同的计算时间，头部的3层模型平均比头部的单层模型的定位误差好2 mm。小于20度的定向误差只能用3层真实模型来检索。定位和定向误差高度依赖于偶极子在大脑中的位置。(C)1999爱思唯尔科学爱尔兰有限公司保留所有权利。
MEG forward problem has been solved for about 2000 dipoles placed on the brain surface using a very fine 3-layer realistic model of the head and the boundary element method (BEM). For each dipole, spherical models, one-layer realistic BEM models and coarser 3-layer realistic BEM models, were used to reconstruct the dipole. It was found that the localization bias induced by using a spherical model of the head increased from 2.5 mm in the upper part of the head to 12 mm in the lower part, on average. It was also found that, for the same computing time, a 3-layer model of the head gave on average 2 mm better localization errors than a one-layer model of the head. Orientation errors of less than 20 degrees could only be retrieved with a 3-layer realistic model. Localization and orientation errors highly depended on the dipole position in the brain. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.