Stokkermans Thomas J, Reitinger Jeremy C, Tye George, Kao Chiu-Yen, Ragupathy Sangeetha, Wang Huachun A, Toris Carol B
University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA.
Case Western Reserve University, Cleveland, Ohio, USA.
J Ophthalmol. 2020 Dec 18;2020:6613066. doi: 10.1155/2020/6613066. eCollection 2020.
This study investigated how a conscious change in ocular accommodation affects intraocular pressure (IOP) and ocular biometrics in healthy adult volunteers of different ages.
Thirty-five healthy volunteers without ocular disease or past ocular surgery, and with refractive error between -3.50 and +2.50 diopters, were stratified into 20, 40, and 60 year old (y.o.) age groups. Baseline measurements of central cornea thickness, anterior chamber depth, anterior chamber angle, cornea diameter, pupil size, and ciliary muscle thickness were made by autorefraction and optical coherence tomography (OCT), while IOP was measured by pneumotonometry. Each subject's right eye focused on a target 40 cm away. Three different tests were performed in random order: (1) 10 minutes of nonaccommodation (gazing at the target through lenses that allowed clear vision without accommodating), (2) 10 minutes of accommodation (addition of a minus 3 diopter lens), and (3) 10 minutes of alternating between accommodation and nonaccommodation (1-minute intervals). IOP was measured immediately after each test. A 20-minute rest period was provided between tests. Data from 31 subjects were included in the study. ANOVA and paired -tests were used for statistical analyses.
Following alternating accommodation, IOP decreased by 0.7 mmHg in the right eye when all age groups were combined ( = 0.029). Accommodation or nonaccommodation alone did not decrease IOP. Compared to the 20 y.o. group, the 60 y.o. group had a thicker ciliary muscle within 75 m of the scleral spur, a thinner ciliary muscle at 125-300 m from the scleral spur, narrower anterior chamber angles, shallower anterior chambers, and smaller pupils during accommodation and nonaccommodation ('s < 0.01).
Alternating accommodation, but not constant accommodation, significantly decreased IOP. This effect was not lost with aging despite physical changes to the aging eye. A greater accommodative workload and/or longer test period may improve the effect.
本研究调查了有意识地改变眼的调节功能如何影响不同年龄健康成年志愿者的眼压（IOP）和眼部生物特征。
35名无眼部疾病或既往眼部手术史、屈光不正度数在-3.50至+2.50屈光度之间的健康志愿者被分为20岁、40岁和60岁年龄组。通过自动验光和光学相干断层扫描（OCT）对中央角膜厚度、前房深度、前房角、角膜直径、瞳孔大小和睫状肌厚度进行基线测量，同时通过眼压计测量眼压。每个受试者的右眼注视40厘米远处的目标。以随机顺序进行三项不同测试：（1）10分钟的非调节状态（通过允许清晰视力而无需调节的镜片注视目标），（2）10分钟的调节状态（添加-3屈光度镜片），（3）10分钟的调节与非调节交替状态（间隔1分钟）。每次测试后立即测量眼压。测试之间提供20分钟的休息时间。研究纳入了31名受试者的数据。采用方差分析和配对检验进行统计分析。
当所有年龄组合并时，交替调节后右眼眼压降低了0.7 mmHg（P = 0.029）。单独的调节或非调节状态均未降低眼压。与20岁组相比，60岁组在距巩膜突75μm范围内的睫状肌更厚，在距巩膜突125 - 300μm处的睫状肌更薄，前房角更窄，前房更浅，并且在调节和非调节状态下瞳孔更小（P < 0.01）。
交替调节而非持续调节可显著降低眼压。尽管随着年龄增长眼睛会发生生理变化，但这种效果不会因衰老而丧失。更大的调节负荷和/或更长的测试时间可能会改善这种效果。
