Kesavaraja C, Sengottuvel S, Patel Rajesh, Selvaraj Raja J, Satheesh Santhosh, Mani Awadhesh
Indira Gandhi Centre for Atomic Research, A CI of Homi Bhabha National Institute, Kalpakkam-603102, Tamil Nadu, India.
SQUIDs Applications section, SQUID & Detector Technology Division, Materials Science Group, Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam-603102, Tamil Nadu, India.
Biomed Phys Eng Express. 2024 Feb 9;10(2). doi: 10.1088/2057-1976/ad233e.
. Magnetocardiography (MCG) is a non-invasive and non-contact technique that measures weak magnetic fields generated by the heart. It is highly effective in the diagnosis of heart abnormalities. Multichannel MCG provides detailed spatio-temporal information of the measured magnetic fields. While multichannel MCG systems are costly, usage of the optimal number of measurement channels to characterize cardiac magnetic fields without any appreciable loss of signal information would be economically beneficial and promote the widespread use of MCG technology.. An optimization method based on the sequential selection approach is used to choose channels containing the maximum signal information while avoiding redundancy. The study comprised 40 healthy individuals, along with two subjects having ischemic heart disease and one subject with premature ventricular contraction. MCG measured using a 37 channel MCG system. After revisiting the existing methods of optimization, the mean error and correlation of the optimal set of measurement channels with those of all 37 channels are evaluated for different sets, and it has been found that 18 channels are adequate.. The chosen 18 optimal channels exhibited a strong correlation (0.99 ± 0.006) between the original and reconstructed magnetic field maps for a cardiac cycle in healthy subjects. The root mean square error is 0.295 pT, indicating minimal deviation.. This selection method provides an efficient approach for choosing MCG, which could be used for minimizing the number of channels as well as in practical unforeseen measurement conditions where few channels are noisy during the measurement.
. 磁心动图(MCG)是一种非侵入性且非接触式的技术,用于测量心脏产生的微弱磁场。它在心脏异常诊断方面非常有效。多通道MCG提供了所测磁场的详细时空信息。虽然多通道MCG系统成本高昂,但使用最佳数量的测量通道来表征心脏磁场,同时又不造成任何明显的信号信息损失,将在经济上带来益处,并促进MCG技术的广泛应用。. 一种基于顺序选择方法的优化方法被用于选择包含最大信号信息且避免冗余的通道。该研究包括40名健康个体,以及两名患有缺血性心脏病的受试者和一名患有室性早搏的受试者。使用37通道MCG系统进行MCG测量。在回顾现有的优化方法后,针对不同的通道集评估了最佳测量通道集与所有37个通道的平均误差和相关性,发现18个通道就足够了。. 在健康受试者中,所选的18个最佳通道在一个心动周期的原始和重建磁场图之间呈现出很强的相关性(0.99±0.006)。均方根误差为0.295 pT,表明偏差极小。. 这种选择方法为选择MCG提供了一种有效途径,可用于减少通道数量,以及在实际中不可预见的测量条件下,即测量过程中少数通道存在噪声的情况。