Bartolić Andrej, Santić Mihovil, Ribaric Samo
Institute of Pathophysiology, Medical Faculty, Zaloska 4, SI-1000 Ljubljana, Slovenia.
Comput Methods Programs Biomed. 2009 Apr;94(1):77-87. doi: 10.1016/j.cmpb.2008.10.007. Epub 2008 Dec 9.
Analysis of tremor amplitude and frequency is often done in frequency domain from tremor power spectra. Several methods for tremor amplitude estimation from power spectra were described but have not been systematically compared and evaluated. In addition, current methods for tremor amplitude estimation from power spectra do not correct tremor amplitude when power spectra of adjacent peaks overlap and this could contribute to an overestimation of tremor amplitude. We developed a computer application for automated analysis of tremor power spectra that corrects tremor amplitude, when power spectra of adjacent peaks overlap, with a Gauss curve fitting method. The accuracy of previously described methods and new methods for tremor amplitude estimation from power spectra was evaluated by 78 simulated power spectra and 900 tremor power spectra records of 25 patients with Parkinson's disease. Thus the influence of peak amplitude, number of peaks and degree of peak overlapping on tremor amplitude estimation could be systematically evaluated and compared. We conclude that the Gauss curve fitting method (Gauss 1) enables a more accurate estimation of tremor amplitude than previously described methods.
震颤幅度和频率的分析通常在频域中通过震颤功率谱进行。已经描述了几种从功率谱估计震颤幅度的方法，但尚未进行系统的比较和评估。此外，当前从功率谱估计震颤幅度的方法在相邻峰值的功率谱重叠时不会校正震颤幅度，这可能导致震颤幅度的高估。我们开发了一种用于自动分析震颤功率谱的计算机应用程序，当相邻峰值的功率谱重叠时，该程序使用高斯曲线拟合方法校正震颤幅度。通过78个模拟功率谱和25例帕金森病患者的900个震颤功率谱记录，评估了先前描述的方法和从功率谱估计震颤幅度的新方法的准确性。从而可以系统地评估和比较峰值幅度、峰值数量和峰值重叠程度对震颤幅度估计的影响。我们得出结论，与先前描述的方法相比，高斯曲线拟合方法（高斯1）能够更准确地估计震颤幅度。
