Clinical Ophthalmology (Aug 2021)
Effect of Low-Level Laser Irradiation on Accommodation and Visual Fatigue
Abstract
Ching-Huang Lin,1 Hsien-Chang Lin,2 Chien-Yu Chen,3 Chong-Chung Lih4 1Department of Electronic Engineering, National Yunlin University of Science & Technology, Yunlin, 640, Taiwan; 2Graduate School of Engineering Science and Technology, National Yunlin University of Science & Technology, Yunlin, 640, Taiwan; 3Graduate Institute of Color and Illumination Technology, National Taiwan University of Science and Technology, Taipei, 106, Taiwan; 4Department of Optometry, Central Taiwan University of Science and Technology, Taichung, 406, TaiwanCorrespondence: Chong-Chung LihDepartment of Optometry, Central Taiwan University of Science and Technology, Taichung, 406, TaiwanTel +866 4 22391647 6981Email [email protected]: This study used low-level laser irradiation on auricular points for the eyes of junior college teenagers with myopia to observe the changes in refractive errors and eye accommodation. According to the Sterner’s study, we used the relationship between the amplitude and subjective symptoms to assess the degree of improvement in visual fatigue caused by changes in accommodation.Methods: Participants were 49 healthy junior college teenagers, with an average age of 16.04± 0.80 years old, and the refractive errors of both eyes were between − 1.50 D and − 5.00 D. All participants underwent refractive error tests before and after class and after a 30-min break. In a 30-min break, all participants underwent two tests of with (experimental group) and without (control group) low-level laser irradiation on the auricular points. Then, refractive error tests were conducted to evaluate the participants’ eye accommodation.Results: The results revealed that with treatment of the auricular points with and without low-level laser irradiation, the refractive error of the participants’ binocular left and right eyes decreased by − 0.12 D (− 0.18 D) in the experimental grou and by − 0.05 D (− 0.02D) in the control group. For the amplitudes of accommodation (AA) examination, the AA of the participants’ binocular in the experimental group became 7.98 ± 1.35 D (7.65 ± 1.37 D). The AA of participants’ binocular can recover to the level before the class.Conclusion: The results indicated that low-level laser irradiation at auricular points restored the eye accommodation faster than did natural closing of the eyes.Keywords: low-level laser irradiation, myopia, teenager, accommodation, auricular point
