운동전위 간섭양상 분석방법에 따른 감별진단 능력의 비교

Abstract

[한글]

간섭양상을 정량적으로 분석하기위한 방법들로는 mean ratio, peak ratio및 cloud 방법등이 보고되고 있다. 본 연구는 신경병증 및 근육병증의 감별진단에 있어서 mean ratio, peak ratio 및 cloud 방법과 같은 정량적 분석방법들의 유용성 및 장단점을 비교 검토하

기 위하여 신경병증 12명, 근육병증 8명의 검사결과를 정상 성인 남녀 각 25, 21명의 정상치와 비교하였다. 간섭양상은 상완 이두근에서 임의로 근수축을 증가시키면서 동축 침전극으로 기록하였으며, 500 msec 단위로 분석하여 다음과 같은 결과를 얻었다.

1. mean ratio는 신경병증 환자 12명 모두에서 신경병증에 합당한 소견을 보였으며, 근육병증 환자 8명중 6명에서 근육병증에 합당한 소견을 보였다.

2. peak ratio는 신경병증 환자 12명중 11명에서 신경병증에 합당한 소견을 보였고, 근육병증 환자 8명중 7명에서 근육병중에 합당한 소견을 보였다.

3. cloud 방법은 신경병증 환자 12명 모두에서 신경병증에 합당한 소견을 보였고, 근육병증 환자 8명 모두에서 근육병증에 합당한 소견을 보여 진단의 민감도가 가장 높았고, 병변의 양상도 비교적 정확히 알 수 있었다.

4. 이들 세가지 분석방법들은 검사상 협조가 어려운 소아의 경우에서도 짧은 시간내에 비교적 간단히 간섭양상을 기록할 수 있어 진단에 도움이 되었다.

이상의 결과로 보아 mean ratio 와 peak ratio는 모두 분석방법이 간단하면서 진단의 민감도가 비교적 높아 일반 근전도 검사시에 같이 시행하면 진단에 도움이 될 것으로 생각한다. cloud 방법은 진단의 민감도가 가장 높았고 병변의 양상도 비교적 정확히 반영하여 일반 근전도상 감별이 어려운 신결병증 및 근육병증의 조기진단에도 도움이 될 것으로 생각한다.

Differential diagnostic abilities of quantitative interference pattern analytic

methods

Jun Soo Park

Department of Medical Science The Graduate School, Yonsei University

(Directed by Professor Kyung Ja Cho)

The electromyographic interference pattern, usually assessed by its appearance on

a screen and it's sound on a speaker, is known to be a difficult task to make an

accurate and objective assessment of the interference pattern. To overcome this

problem, several methods to quantify the interference pattern such as mean ratio,

peak ratio and Nandedkar's cloud method have been developed.

So, we used all three of these interference pattern analytic methods

simultaneously in 46 normal subjects, 12 neuropathies and 8 myopathies, to

investigate which of these methods represent the characteristics of the motor unit

action potential (MUAP) in neuropathy and myopathy more accurately.

The interference pattern were measured at the biceps brachii muscle with

concentric needle electrode while the subject contracting the muscle at various

degree, and the number of turn, mean amplitude, complexity, upper centile amplitude

and activity were analysed.

The results are as follows :

1. All 12 patients with neuropathy(100%) and 6 out of 8 patients with

myopathy(75%) had mean ratio above and below the control group range.

2. 11 out of 12 patients with neuropathy(91.7%) and 7 out of 8 patients with

myopathy(87.5%) had peak ratio below and above the control group range.

3. All 12 neuropathy(100%) and all 8 myopathy(100%) patients showed abnormal

findings in the cloud method.

4. These three analysis methods were very useful in uncooperative patients and

children in the conventional needle electromyography.

On the basis of this study, mean ratio and peak ratio methods were found to be a

relatively sensitive tools in the evaluation of neuropathic or myopathic disease

activity and that they could be done with ease. The Nandedkar's cloud method was

most sensitive and represented the characteristics of the MUAP of neuropathy and

myopathy most accurately and ebjectively. Further studies are recommanded for the

evaluation of monitoring the various neuropathic and myopathlc disease activity and

it's progression.

[영문]

The electromyographic interference pattern, usually assessed by its appearance on a screen and it's sound on a speaker, is known to be a difficult task to make an accurate and objective assessment of the interference pattern. To overcome this

problem, several methods to quantify the interference pattern such as mean ratio, peak ratio and Nandedkar's cloud method have been developed.

So, we used all three of these interference pattern analytic methods simultaneously in 46 normal subjects, 12 neuropathies and 8 myopathies, to investigate which of these methods represent the characteristics of the motor unit action potential (MUAP) in neuropathy and myopathy more accurately.

The interference pattern were measured at the biceps brachii muscle with concentric needle electrode while the subject contracting the muscle at various degree, and the number of turn, mean amplitude, complexity, upper centile amplitude and activity were analysed.

The results are as follows :

1. All 12 patients with neuropathy(100%) and 6 out of 8 patients with myopathy(75%) had mean ratio above and below the control group range.

2. 11 out of 12 patients with neuropathy(91.7%) and 7 out of 8 patients with myopathy(87.5%) had peak ratio below and above the control group range.

3. All 12 neuropathy(100%) and all 8 myopathy(100%) patients showed abnormal findings in the cloud method.

4. These three analysis methods were very useful in uncooperative patients and children in the conventional needle electromyography.

On the basis of this study, mean ratio and peak ratio methods were found to be a relatively sensitive tools in the evaluation of neuropathic or myopathic disease activity and that they could be done with ease. The Nandedkar's cloud method was most sensitive and represented the characteristics of the MUAP of neuropathy and myopathy most accurately and ebjectively. Further studies are recommanded for the evaluation of monitoring the various neuropathic and myopathlc disease activity and it's progression.