Derivatives and Fourier Frequency Analysis of Evoked Muscle Potentials

Year 1982, Volume: 35 Issue: 4, 727 - 736, 31.12.1982

İsmail Günay

Abstract

This study evaluates evoked muscle potentials recorded from the extensor digitorum brevis (EDB) using surface electrodes and analyzes them via differentiation and Fourier frequency techniques. A total of 51 cases were divided into four groups: normal (n=21), neurogenic (n=16), myogenic (n=9), and suspected (n=5). Signals were obtained using the DISA 1500 digital EMG system. The derivative method determined rates and amplitudes of potential changes, while Fourier analysis assessed frequency spectra. The mean dominant frequency was 88.4 Hz for the normal group and 61 Hz for the neurogenic group. The most distinguishing parameter was (dx/dt) min, which was significantly lower in neurogenic cases. This parameter is proposed to have practical diagnostic value for identifying neurogenic lesions.

Keywords

kas , potansiyel , frekans

Uyarılmış Kas Potansiyellerinin Türev ve Fourier Frekans Analizleri

Abstract

Bu çalışma, yüzeyel elektrotlarla extensör digitorum brevis (EDB) kasından alınan uyarılmış kas potansiyellerinin türev ve Fourier frekans analizi teknikleriyle değerlendirilmesini amaçlamaktadır. Toplam 51 vaka dört gruba ayrılmıştır: normal (n=21), nörojenik (n=16), miyojenik (n=9), şüpheli (n=5). Elde edilen sinyaller DISA 1500 dijital EMG sistemi ile kaydedilmiş, türev tekniği ile potansiyel değişim hızları ve büyüklükleri belirlenmiş; Fourier analiziyle frekans spektrumları incelenmiştir. Normal grupta dominant frekans ortalaması 88,4 Hz iken nörojenik grupta 61 Hz bulunmuştur. En önemli ayırt edici parametre (dx/dt) min olup nörojenik grupta belirgin şekilde düşük saptanmıştır. Bu parametrenin nörojenik lezyonların tanısında pratik bir değeri olduğu belirtilmiştir.

Keywords

kas , potansiyel , frekans

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