Kajita Eye Clinic, Kyoei Building, 4F, 3-6-3, Shibaura, Minato-ku, Tokyo, Japan.
CooperVision Japan, Inc., 2-36-13, Ebisu, Shibuya-Ku, Tokyo, Japan.
Cont Lens Anterior Eye. 2020 Oct;43(5):493-496. doi: 10.1016/j.clae.2020.03.003. Epub 2020 Mar 19.
Accommodative micro-fluctuations (AMF) are small dioptric changes during accommodation. The aim of this study was to evaluate and compare changes in AMF when wearing silicone hydrogel contact lenses of two different optical designs.
A multi-centre, randomised, cross-over, non-dispensing study was conducted on 68 adapted contact lens wearers aged 25-35 years to compare AMF responses to a spherical and aspheric silicone hydrogel (comfilcon A) lens designs. A Righton Speedy "i" series Auto Refractometer in accommodation analyser mode was utilized before and after reading a standard text in font size 8 on an iPhone 5 for 20 min at a 25 cm viewing distance. Phone screen brightness was set by automatic adjustment mode and ambient illumination was controlled at all sites.
Mean ± SD AMF change from before to after the reading task was 2.25 ± 5.6 and 0.13 ± 5.7 (relative values) for the spherical and aspheric lens designs, respectively. The difference was statistically significant (P = 0.017, Paired t-test).
The smaller change in AMF when using an aspheric lens design suggests reduced ciliary muscle stress when reading print on a smart phone at a close distance for short periods (20 min). Contact lens wearers who frequently use digital devices and are experiencing eye strain may benefit from switching from a spherical design to one that incorporates aspheric optics.
调节性微波动（AMF）是调节过程中的微小屈光度变化。本研究旨在评估和比较两种不同光学设计的硅水凝胶隐形眼镜佩戴者的 AMF 变化。
一项多中心、随机、交叉、非处方研究招募了 68 名年龄在 25-35 岁之间适应接触镜佩戴的患者，比较了 AMF 对球面和非球面硅水凝胶（comfilcon A）镜片设计的反应。使用 Righton Speedy“i”系列自动折射仪在调节分析器模式下，在阅读 iPhone 5 上 8 号字体的标准文本 20 分钟（在 25cm 的观看距离）前后进行测量。手机屏幕亮度设置为自动调节模式，所有地点的环境照明均受控制。
阅读任务前后的平均 AMF 变化分别为球面和非球面镜片设计的 2.25±5.6 和 0.13±5.7（相对值）。差异具有统计学意义（P=0.017，配对 t 检验）。
在使用非球面镜片设计时，AMF 的变化较小，这表明在智能手机上近距离阅读短时间（20 分钟）内睫状肌的压力较小。经常使用数字设备并出现眼睛疲劳的隐形眼镜佩戴者可能会从球面设计切换到包含非球面光学元件的设计中受益。
