Aldossari Hussain, Suheimat Marwan, Atchison David A, Schmid Katrina L
*PhD †DSc, FAAO School of Optometry and Vision Science and Institute of Health and Biomedical Innovation, Faculty of Health, Queensland University of Technology, Kelvin Grove, Queensland, Australia (all authors).
Optom Vis Sci. 2017 Mar;94(3):361-369. doi: 10.1097/OPX.0000000000001037.
To investigate the effect of accommodation on central and peripheral axial lengths in young adult emmetropes and myopes.
On-axis and peripheral axial lengths were measured with the Haag-Streit Lenstar in 83 young adult participants for 0D and 6D accommodation demands. A Badal system was used to both correct refractive errors and induce accommodation. Participants were emmetropes (n = 29, mean spherical equivalent refraction +0.35 ± 0.35D), low myopes (32, -1.38 ± 0.73D), and higher myopes (22, -4.30 ± 0.73D). Ages were similar for all groups (22 ± 2 years). Pupils were dilated with 2.5% phenylephrine to allow a large field of measurement while maintaining active accommodation. Axial lengths were measured in 5° steps to ±30° across the horizontal visual field.
With accommodation, axial length increased for all refractive groups at all positions, but with lessening effect away from fixation. Axial length changes were greater for higher myopes than for emmetropes on-axis (higher myopes 41 ± 14 μm, emmetropes 30 ± 12 μm, P = .005), for higher myopes than for low myopes at 30° nasal (P = .03), and for the higher myopes than for the other groups at 20° nasal (P < .05). There were significant correlations between myopia and changes in axial length at all positions, with the highest correlation on-axis (R = 0.30, P < .001).
During accommodation, eye length increased out to at least ±30° visual angle in young adult myopes and emmetropes. The increase was significantly greater for higher myopes than for the other groups at some positions. At all positions, there were significant correlations between myopia and accommodation-induced changes in axial length.
研究调节对年轻成人正视眼和近视眼中央及周边眼轴长度的影响。
使用Haag-Streit Lenstar测量83名年轻成人参与者在0D和6D调节需求下的轴上和周边眼轴长度。使用Badal系统矫正屈光不正并诱导调节。参与者包括正视眼（n = 29，平均球镜等效屈光度+0.35±0.35D）、低度近视眼（32人，-1.38±0.73D）和高度近视眼（22人，-4.30±0.73D）。所有组的年龄相似（22±2岁）。用2.5%去氧肾上腺素散瞳，以在保持主动调节的同时获得较大的测量视野。在水平视野中以5°步长测量至±30°的眼轴长度。
随着调节，所有屈光组在所有位置的眼轴长度均增加，但离注视点越远影响越小。在轴上，高度近视眼的眼轴长度变化大于正视眼（高度近视眼41±14μm，正视眼30±12μm，P = 0.005）；在鼻侧30°处，高度近视眼的眼轴长度变化大于低度近视眼（P = 0.03）；在鼻侧20°处，高度近视眼的眼轴长度变化大于其他组（P < 0.05）。在所有位置，近视与眼轴长度变化之间均存在显著相关性，轴上相关性最高（R = 0.30，P < 0.001）。
在年轻成人近视眼和正视眼中，调节时眼轴长度增加至少至±30°视角。在某些位置，高度近视眼的增加幅度明显大于其他组。在所有位置，近视与调节引起的眼轴长度变化之间均存在显著相关性。
