Scheffler A, Rieger H
Group for Clinical Hemorheology and Experimental Angiology, RWTH Aachen, Engelskirchen, FRG.
Int J Microcirc Clin Exp. 1990 Nov;9(4):357-68.
Results of local skin perfusion measurements performed by laser-Doppler-fluxmetry (LDF) are generally expressed in terms of relative mean values of time constants of signal responses to various procedures. In addition, information is obtained from the frequency and amplitude of temporal signal variations. In this report, a microcomputer system designed for recording, storage, artifact elimination, evaluation, and documentation of LDF measurements will be described. This system consists of a desk-top computer with additional hardware necessary for digital data acquisition and acceleration of mathematical operations. A three-phase model defined by a control, a transient, and an effect interval was programmed in order to standardize calculations within the time domain. For spectral analysis of periodical signal fluctuations, an algorithm was implemented based on a Fast-Fourier-Transformation (FFT) in combination with an optional averaging of several spectra within the frequency domain. Clinical measurements performed on patients with peripheral arterial occlusive disease (PAOD) and healthy volunteers illustrate the features of the system.
通过激光多普勒血流仪（LDF）进行的局部皮肤灌注测量结果通常以对各种程序的信号响应时间常数的相对平均值来表示。此外，还可从时间信号变化的频率和幅度获取信息。在本报告中，将描述一种用于记录、存储、消除伪迹、评估和记录LDF测量结果的微型计算机系统。该系统由一台台式计算机以及数字数据采集和加速数学运算所需的附加硬件组成。为了在时域内规范计算，编制了一个由控制期、瞬态期和效应期定义的三相模型。对于周期性信号波动的频谱分析，基于快速傅里叶变换（FFT）并结合在频域内对多个频谱进行可选平均的算法得以实现。对患有外周动脉闭塞性疾病（PAOD）的患者和健康志愿者进行的临床测量说明了该系统的特点。
