목적: 콘택트렌즈 착용시 렌즈가 각막에 부착된 상태를 정확하게 파악하기 위해서는 콘택트렌즈 운동에 대한 이해가 필요하다. 이 중 순목에 수반되는 렌즈의 움직임은 각막에 산소 공급 뿐 아니라 안정된 교정시력을 확보할 수 있다는 점에서도 매우 중요하다. 방법: 순목시 콘택트렌즈의 위치 이동은 눈꺼풀이 렌즈를 누르는 압력, 안쪽 눈꺼풀과 콘택트렌즈 사이의 미끄럼 마찰, 순목에 소요되는 시간, 눈꺼풀이 움직이는 최대 수직거리 등에 의해 결정되므로 순목 직후의 콘택트렌즈 위치는 이러한 순목 관련 요소와 함수관계에 있다고 생각할 수 있다. 결과: 눈꺼풀과 렌즈의 마찰력이 관여하는 눈꺼풀의 운동을 설명할 수 있고, 순목시 콘택트렌즈의 직경, 순목시간, 눈꺼풀의 압력 등의 변수에 따른 콘택트렌즈 위치 및 콘택트렌즈 착용시 발생할 수 있는 문제점을 예측할 수 있는 뉴턴의 운동 방정식 모델을 수립하였다. 결론: 본 연구의 운동방정식 모델을 측정 가능한 변수인 순목 속도와 눈꺼풀 두께를 이용한 선행된 임상연구와 비교한 결과 좋은 일치를 보여 타당성을 확인할 수 있었다.

The purpose of this study was to obtain correlation of blinking velocities and RGP contact lens movements, and to understand lens movements related to blinking velocity through the measurement of upper-lid movement. The lens used in this experiment was two types. One was a standard contact lens and another was a fenestrated contact lens that has three holes(diameter of about 200 11m) at optic zone boundary part. But all of parameter were same in two type of contact lens design. With 4 7 subjects(94 eyes), we measured the refractive error, the radius of cornea curvature, the axial length and the thickness of upper-lid. We measured blinking times per second and the contact lens movement after blinking by high speed camera(l frame = 1/60 sec). Blinking average velocity of upper lid and lens movement amount were no significant correlation both two types of contact lenses, but the blinking average velocity and lens reorientation velocity after blinking showed significant correlation (Standard C!L: r = 0.586, Fenestrated C!L: r = 0.504). Mean difference of reorientation velocity between low and high groups in blinking average velocity was significant as well(Standard C/L: p = 0.002, Fenestrated C/L: p = 0.003). There was no statistically different of lens movement amount in standard and fenestrated contact lenses. But reorientation velocity of standard contact lens was faster than fenestrated contact lens(p = 0.002). There was no significant correlation between blinking velocity of upper-lid and lens movement and rotation. While it had strong correlation with blinking velocity and reorientation velocity. lt might be understood through the approach of Bernoulli's equation that is being used commonly in fluid mechanics. As mentioned above, this study is considerably used to evaluate contact lens movements related to blinking and to make some basic information that the upper-lid has an effect on contact lens fitting.