A Study on Classification of Heart Sounds Using Hidden Markov Models

Hidden Markov Model을 이용한 심음분류에 관한 연구

  • 김희근 (계명대학교 전자공학과) ;
  • 정용주 (계명대학교 전자공학과)
  • Published : 2006.04.01

Abstract

Clinicians usually use stethoscopic auscultation for the diagnosis of heart diseases. However, the heart sound signal has varying characteristics due to the noise and/or the conditions of the patients. Also, it is not easy for junior clinicians to find the acoustical differences between different kinds or heart sound signals. which may result in errors in the diagnosis. Thus it will be quite useful for the clinicians to make use of an automatic classification system using signal processing techniques. In this paper, we propose to use hidden Markov models in stead of artificial neural networks which have been conventionally used for the automatic classification of heart sounds. In the experiments classifying heart sound signals. we could see that the proposed methods were quite successful in the classification accuracy.

심장병이 있는 환자들을 진료할 때 의사들은 청진기를 이용하여 심음 (heart sound)을 듣고 이를 기준으로 환자의 병의 유무나 질환의 종류에 대한 기초적인 판단을 하게 된다. 하지만, 심음은 환자의 상태나 외부 잡음의 영향에 따라서 신호의 특성이 변하고 또한 정상적인 심음과 질병을 나타내는 심음과의 차이가 비교적 구분하기 어려울 정도로 작기 때문에 숙달된 전문의가 아니면, 진단의 정확도가 떨어질 가능성이 있다. 따라서 신호처리 기법을 이용하여 심음을 분석해서 심음이 정상적인지의 유무를 자동으로 판단할 수 있다면, 진단을 하는 의사들에게 유용한 정보가 될 것이라 생각된다. 본 연구에서는 심음의 질병유무와 질병종류를 자동으로 판단하기 위해서 기존에 많이 사용되었던 artificial neural network (ANN) 대신에 hidden Markov model (HMM)을 사용하는 방법을 제안하였으며, 기초적인 실험결과 상당히 우수한 성능을 보임을 알 수 있었다.

Keywords

References

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