Tomii Naoki, Yamazaki Masatoshi, Arafune Tatsuhiko, Honjo Haruo, Shibata Nitaro, Sakuma Ichiro
IEEE Trans Biomed Eng. 2016 Sep;63(9):1795-1803. doi: 10.1109/TBME.2015.2502726. Epub 2015 Nov 20.
Spiral reentry is a recognized cause of tachycardia. Detection and tracking of the spiral core are essential for understanding the spiral wave dynamics. The core of the spiral corresponds to a phase singularity (PS), which can be identified in an optical mapping image by a kernel convolution method. However, because of a large number of false positives, this method cannot automatically and stably track the core of sustaining spiral reentry in optical mapping data.
We developed a new PS detection algorithm that quantifies the variance of phase values in a phase map and identifies the position of PS as its peak.
In comparison with the kernel convolution method, our method improved the precision of detecting a single sustaining spiral wave core from 73.1% to 99.8%. The precision of the proposed method for virtual-electrode-polarization-induced multiple PSs detections was also higher than the convolutional method.
The proposed method detects PS by finding the peaks in the phase variance distribution of cardiac optical mapping image. It improved the precision of the core detection of the spiral wave in cardiac optical mapping images in comparison with the conventional kernel convolution method.
The proposed method will reveal the spiral wave dynamics in optical mapping images better than existing approaches. The objective analysis method of a spiral wave is important for understanding the mechanisms and dynamics of serious heart arrhythmias.
螺旋形折返是心动过速的一个公认原因。检测和追踪螺旋波核心对于理解螺旋波动力学至关重要。螺旋波的核心对应于一个相位奇点（PS），它可以通过内核卷积方法在光学标测图像中识别出来。然而，由于存在大量误报，该方法无法在光学标测数据中自动且稳定地追踪持续螺旋形折返的核心。
我们开发了一种新的PS检测算法，该算法量化相位图中相位值的方差，并将PS的位置识别为其峰值。
与内核卷积方法相比，我们的方法将检测单个持续螺旋波核心的精度从73.1%提高到了99.8%。所提出的方法用于检测虚拟电极极化诱导的多个PS的精度也高于卷积方法。
所提出的方法通过在心脏光学标测图像的相位方差分布中寻找峰值来检测PS。与传统的内核卷积方法相比，它提高了心脏光学标测图像中螺旋波核心检测的精度。
所提出的方法将比现有方法更好地揭示光学标测图像中的螺旋波动力学。螺旋波的客观分析方法对于理解严重心律失常的机制和动力学很重要。
