Change of Fixation Disparity and Accommodation when the Fusion Contrast Varied

융합대비에 따른 주시시차와 조절의 변화

  • 서재명 (광주보건대학 안경광학과)
  • Received : 2009.10.31
  • Accepted : 2009.12.08
  • Published : 2009.12.31

Abstract

Purpose: To study the change of fixation disparity and accommodation as fusion contrast is deteriorated. Methods: 16 subjects who had above 20/20 and stereopsis took part. Monocular and binocular refraction were done with Zeiss Polatest Classic whereas the critical angle for stereopsis was done with TNO. A computer programmed with Random-Dot stereogram and vernier test managed a precise change of the fusion contrast and exposure time. Results: The fixation disparity was influenced by reduction of fusion contrast and had tendancy to exophoria (p=0.0004), especially it is considerably higher when uncrossed disparity was shown to exophoric subjects. Although accommodation was not influenced by a change of fusion contrast (p=0.803), vernier acuity was influenced (p=0.0000). Conclusions: Exophoric trend arose as the fusion contrast was reduced, nevertheless there was no accommadative change.

목적: 융합대비의 변화에 따른 주시시차를 추적하며 동시에 버전스 체계와 밀접한 조절의 관계를 확인해 보고자 한다. 방법: 양안 교정시력이 1.0이상이며 입체시 지각이 확인된 16명을 대상으로 하였다. 굴절 및 양안시 검사는 Zeiss Polatest Classic을 사용하였으며 입체시차는 TNO를 사용하여 측정하였다. 난점 입체시표와 배열시표는 프로 그램화 된 컴퓨터를 사용하여 대비의 변화와 시간을 정확히 제어하였다. 결과: 주시시차는 융합대비의 감소에 따라 안구는 외전성 경향을 보였다(p=0.0004). 외사위안에서 비교차성 비대응 결상시 융합대비가 감소할수록 외전현상이 더욱 두드러졌다. 융합대비의 변화는 조절에 영향을 주지 않았지만(p=0.803) 배열시표에는 영향을 주는 것으로 밝혀졌다(p=0.0000). 결론: 융합대비가 저하될수록 안구는 외전성 경향을 보이나 조절의 변화는 없다.

Keywords

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