Evaluation of the Cochlear Electrode Behavior in the 3D Human Cochlea Model by FEM Analysis

3차원 달팽이관 모델에서의 인공와우 전극의 거동에 대한 유한요소해석

  • 임윤섭 (서울대학교 전기컴퓨터 공학부) ;
  • 박세익 (서울대학교 전기컴퓨터 공학) ;
  • 김용협 (서울대학교 기계항공공학) ;
  • 오승하 (서울대학교 의과대학 이비인후) ;
  • 김성준 (서울대학교 전기컴퓨터 공학부)
  • Published : 2004.06.01

Abstract

A finite element analysis is used in this study to model 6 kinds of electrode by a genetic program in order to evaluate the mechanical effect on the 3D human cochlea model and the behavior of electrode. Human cochlea is modeled by the spiral-approximation method and the shape of scala tympani is extracted from the mid section of the human cochlea. Contact pressure at the tip and the insertion force are found to be highest when the wires stack horizontally. Axial rotation of electrode is minimal comparing with the stimulating current spread. The results indicate that the electrode stiffness is important to minimize the trauma.

본 연구에서는 유전 프로그램을 이용하여 6가지 형태의 금속 와이어 배치를 가진 전극을 생성하여 각 전극이 3차원 형태의 달팽이관에 미치는 기계적인 영향과 그 거동을 유한요소법을 이용하여 분석하였다. 그리고 전극이 삽입되는 달팽이관은 helico-spiral 근사방법에 의해 결정된 식을 이용하였으며, 고실계단(scala tympani)의 형태는 실제 고실계단 단면의 영상정보를 추출하여 얻어내었다. 해석결과 금속 와이어가 평행하게 배치될 경우 가장 큰 힘을 달팽이관 외벽에 전달하며, 삽입에도 가장 큰 힘이 필요한 것을 알 수 있었다. 그리고 달팽이관은 3차원 구조이므로 전극이 삽입되면서 삽입 전에 자극 사이트가 바라보도록 설정한 방향보다 조금 돌아감을 확인하였다. 이 연구의 결과로부터 전극의 강성이 외상(trauma)을 줄이는데 중요하다는 것을 알 수 있다.

Keywords

References

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