Influence of body parameters on gastric bioelectric and biomagnetic fields in a realistic volume conductor.
Influence of body parameters on gastric bioelectric and biomagnetic fields in a realistic volume conductor.
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DOI：
10.1088/0967-3334/33/4/545
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发表时间：
2012-04
影响因子：
3.2
通讯作者：
Cheng LK
中科院分区：
文献类型：
--
作者：
Kim JH;Pullan AJ;Bradshaw LA;Cheng LK
胃电图（EGG）和胃磁图（MGG）提供了两种互补的方法，用于非侵入性地记录由胃电慢波活动引起的电场或磁场。众所周知，EGG信号相对较弱，难以可靠地记录，而磁场在理论上较少被体内存在的低电导率脂肪层衰减。在本文中，我们量化的脂肪厚度和电导率值对所得磁场和电场的影响，使用解剖学上逼真的躯干模型和列车的偶极子源反映最近的实验结果。结果表明，当脂肪电导率增加时，电位和磁场的变化都很小。然而，当脂肪电导率降低时，磁场基本不变，但电势的模式和幅度发生了显着变化。当脂肪层的厚度增加30 mm时，磁场的幅度比电势降低10%以上，但磁场模式的变化比电势小约4倍。当脂肪层增加30 mm时，使用表面电流密度测量从磁场定位底层源的能力被改变了不到2 mm。总之，结果证实，当脂肪厚度或电导率水平不确定时，MGG提供了一种优于EGG的方法。
Electrogastrograms (EGG) and magnetogastrograms (MGG) provide two complementary methods for non-invasively recording electric or magnetic fields resulting from gastric electrical slow wave activity. It is known that EGG signals are relatively weak and difficult to reliably record while magnetic fields are, in theory, less attenuated by the low-conductivity fat layers present in the body. In this paper we quantified the effects of fat thickness and conductivity values on resultant magnetic and electric fields using anatomically realistic torso models and trains of dipole sources reflecting recent experimental results. The results showed that when the fat conductivity was increased there was minimal change in both potential and magnetic fields. However, when the fat conductivity was reduced the magnetic fields were largely unchanged, but electric potentials had a significant change in patterns and amplitudes. When the thickness of the fat layer was increased by 30 mm the amplitude of the magnetic fields decreased 10 % more than potentials but magnetic field patterns were changed about 4 times less than potentials. The ability to localize the underlying sources from the magnetic fields using a surface current density measure was altered by less than 2 mm when the fat layer was increased by 30 mm. In summary, results confirm that MGG provides a favourable method over EGG when there are uncertain levels of fat thickness or conductivity.
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影响因子：
4.6
作者：
Bradshaw, LA;Ladipo, JK;Richards, WO
通讯作者：
Richards, WO
影响因子：
3.5
作者：
Bradshaw, LA;Myers, AG;Richards, WO
通讯作者：
Richards, WO
影响因子：
3.4
作者：
Du, Peng;O'Grady, Gregory;Pullan, Andrew J.
通讯作者：
Pullan, Andrew J.
DOI：
10.1136/jamia.1996.96236280
发表时间：
1996-03-01
影响因子：
6.4
作者：
Spitzer, V;Ackerman, MJ;Whitlock, D
通讯作者：
Whitlock, D
影响因子：
3
作者：
HINDER, RA;KELLY, KA
通讯作者：
KELLY, KA