Fink B A, Hill R M, Carney L G
College of Optometry, Ohio State University, Columbus.
Optom Vis Sci. 1993 Oct;70(10):781-4. doi: 10.1097/00006324-199310000-00001.
To evaluate the effects of base curve radius, overall diameter, and axial edge lift on rigid contact lens tear pump efficiency, corneal oxygen uptake rates were measured on six eyes under three conditions: normal open eye, after 5 min of static (without blinking) wear, and after 5 min of dynamic (with blinking once every 5 s) wear. The three parameters were varied one at a time from a standard lens design. Differences in corneal oxygen demands between the static and dynamic rates provided quantitative measures of the tear pump efficiency for each lens design. Tear exchange was found to be most sensitively related to changes in base curve radius, followed by overall diameter changes (66.9% as effective) and axial edge lift changes (64.6% as effective). Design equivalencies (to produce identical tear exchange to a 0.05-mm flattening of base curve toward alignment) were 0.07-mm steepening of the base curve toward alignment, 0.35-mm decrease in overall diameter, or 0.037-mm increase in axial edge lift.
为评估基弧半径、总直径和轴向边缘抬高对硬性角膜接触镜泪液泵效率的影响，在三种情况下测量了六只眼睛的角膜氧摄取率：正常睁眼、静态（不眨眼）佩戴5分钟后以及动态（每5秒眨眼一次）佩戴5分钟后。这三个参数每次从标准镜片设计开始逐一变化。静态和动态速率之间角膜氧需求的差异为每种镜片设计的泪液泵效率提供了定量测量。发现泪液交换与基弧半径变化最敏感相关，其次是总直径变化（有效性为66.9%）和轴向边缘抬高变化（有效性为64.6%）。设计等效性（产生与基弧向对齐方向扁平化0.05毫米相同的泪液交换）为基弧向对齐方向变陡0.07毫米、总直径减小0.35毫米或轴向边缘抬高增加0.037毫米。
