Morad M, Dillon S, Weiss J
Soc Gen Physiol Ser. 1986;40:211-26.
An optical scanning device that combines a voltage-sensitive dye and an acousto-optically steered He-Ne laser beam is described. This device is capable of scanning 128 sites every 4 ms and recording and storing the fluorescence signals for a duration of up to 1 s (several beats). Comparison of an activation map constructed from laser scanning to those obtained from multiple extracellular electrodes suggests that this technique is highly reliable. Although motion-induced light scattering appears to alter the shape of the action potential, the upstroke can be distinguished quite reliably even in a vigorously contracting muscle. This technique provides high resolution (up to 50 micron) and high flexibility (i.e., the scanned sites can be concentrated over a small or very large area) in measuring the spread of activation in heart muscle. By having only one excitation and one measurement element, the approach offers simplicity and high flexibility to the user. We have shown that this system can be readily applied to the task for which it was intended--probing the mechanisms of arrhythmias in the mammalian myocardium. It has been demonstrated, for example, that arrhythmias due to automaticity can be readily distinguished from those due to reentry through the mapping capability of the laser scanner. In addition, the ability of laser scanner to measure membrane depolarization directly during arrhythmias may make this technique superior to conventional electrocardiographic mapping techniques.
本文描述了一种光学扫描装置，它将电压敏感染料与声光控制的氦氖激光束相结合。该装置能够每4毫秒扫描128个位点，并记录和存储荧光信号，持续时间长达1秒（几个心动周期）。将激光扫描构建的激活图与多个细胞外电极获得的激活图进行比较表明，该技术高度可靠。尽管运动引起的光散射似乎会改变动作电位的形状，但即使在剧烈收缩的肌肉中，也能相当可靠地分辨出上升支。该技术在测量心肌激活的传播方面具有高分辨率（高达50微米）和高灵活性（即扫描位点可以集中在小面积或非常大的区域）。通过仅具有一个激发元件和一个测量元件，该方法为用户提供了简单性和高灵活性。我们已经表明，该系统可以很容易地应用于其设计目的——探究哺乳动物心肌心律失常的机制。例如，已经证明，通过激光扫描仪的映射能力，可以很容易地将自律性引起的心律失常与折返引起的心律失常区分开来。此外，激光扫描仪在心律失常期间直接测量膜去极化的能力可能使该技术优于传统的心电图映射技术。
