Accommodative Exercises to Lower Intraocular Pressure.

Thomas J Stokkermans,Chiu-Yen Kao,Carol B Toris,Huachun A Wang,Jeremy C Reitinger,Sangeetha Ragupathy,George Tye,Ciro Costagliola

doi:10.1155/2020/6613066

Abstract

Purpose This study investigated how a conscious change in ocular accommodation affects intraocular pressure (IOP) and ocular biometrics in healthy adult volunteers of different ages. Methods 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 t-tests were used for statistical analyses. Results Following alternating accommodation, IOP decreased by 0.7 mmHg in the right eye when all age groups were combined (p = 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 μm of the scleral spur, a thinner ciliary muscle at 125–300 μm from the scleral spur, narrower anterior chamber angles, shallower anterior chambers, and smaller pupils during accommodation and nonaccommodation (p's < 0.01). Conclusion 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.

Highlights

Slowing of glaucoma progression is accomplished primarily by management of intraocular pressure (IOP) through pharmacological and surgical methods
The subject rotated his/her head to the right so that the right eye could see a distant target on the wall 10 feet away and the temporal ciliary muscle of the left eye was clearly visible on the optical coherence tomography (OCT) screen
Data from the first three subjects were omitted after changes in study design were made to optimize the timing of test periods and physical layout of the lens and OCT imaging. irty-one subjects completed the study with the new study design (Table 1)

Summary

Accommodative Exercises to Lower Intraocular Pressure

Is study investigated how a conscious change in ocular accommodation affects intraocular pressure (IOP) and ocular biometrics in healthy adult volunteers of different ages. IOP was measured immediately after each test. IOP decreased by 0.7 mmHg in the right eye when all age groups were combined (p = 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 μm of the scleral spur, a thinner ciliary muscle at 125–300 μm from the scleral spur, narrower anterior chamber angles, shallower anterior chambers, and smaller pupils during accommodation and nonaccommodation (p’s < 0.01). Alternating accommodation, but not constant accommodation, significantly decreased IOP. A greater accommodative workload and/or longer test period may improve the effect

Introduction

Methods

Results

Test Group