Training regimen involving cyclic induction of pupil constriction during far accommodation improves visual acuity in myopic children
Kenji Yuda1, Hiroshi Uozato2, Naoto Hara3, Wolfram Tetzlaff4, Satoru Hisahara5, Hiroko Horie6, Satomi Nakajima6, Hidenori Horie6,7
1Kikuna Yuda Eye Clinic, Yokohama, Japan; 2Department of Ophthalmology and Visual Science, Kitasato University, Kanagawa, Japan; 3Department of Ophthalmology, Yokohama Dental and Medical Clinic, Kanagawa Dental College, Yokohama, Japan; 4ICORD, International Collaboration on Repair Discoveries, Univ. of British Columbia, Vancouver, BC, Canada; 5Panasonic Shikoku Electronics Co., Ltd., Yokohama, Japan; 6TechnoMaster Co., Ltd., Yokohama, Japan; 7Research Center of Brain and Oral Science, Kanagawa Dental College, Yokosuka, Japan
Purpose: Myopia in school-age children has become increasingly prevalent in industrialized countries, especially in Asia. A large population of school-age children still suffers from low visual acuity. We have developed a novel, safe and noninvasive training method to activate a pupillary constriction response during far accommodation that results in improved visual acuity.
Methods: Myopic children (n = 95) were treated for 3-minute sessions up to twice a week for 12–106 weeks. We stimulated quick cycles of near/far accommodation by displaying a visual object on a LCD screen and moving the screen in cycles from a near (25 cm) to a far (70 cm) point and back, while keeping the retinal projection size and brightness of the object constant.
Results: Mechanistically, we noted pupillary constriction upon far accommodation in trained myopic children, which was not seen in normal subjects or in untrained myopic children. Eighty five percent (52/61) of trained myopic right eyes with two sessions weekly experienced improved visual acuity (VA) by more than 0.1 logMAR units with an average improvement of 0.30 ± 0.03 standard error of mean (SEM) logMAR units. With maintained training, most eyes’ improved VA stayed almost constant, for more than 50 weeks in the case of 12 long trained subjects.
Conclusions: This simple, short and safe accommodation training greatly improves the quality of vision in a large population suffering from refractive abnormalities.
Keywords: accommodation, visual acuity, myopia, pupil constriction, training regimen
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