Abstract
Purpose :
In this age of digital devices, failure to successfully manage presbyopia may lead to not only eye strain, but also headache and shoulder and neck pain, resulting in lower productivity. The present study aimed to objectively verify the effect of wearing multifocal soft contact lenses (SCLs; DAILIES TOTAL1 MULTIFOCAL®) on reducing asthenopia in visual display terminal (VDT) workers with pre-presbyopia based on changes in visual function.
Methods :
A total of 20 participants, 6 men and 14 women with a mean age of 44.0 ± 4.2 years, were asked to wear SCL before they began their VDT work for their entire day. The effect of the 60 days SCL wear on asthenopia was evaluated by subjective and objective test. On Days 1, 7, 30, and 60 of SCL wear, visual acuity, phoria, and objective accommodative function (AA-2000©) tests were performed to take measurements of the tonic rest state of accommodation (TA), accommodative power (AP), and accommodative lag (AL) before and after their shift. In addition, the subjects were evaluated by electroencephalography (EEG) (Kansei©) and the Computer Vision Syndrome Questionnaire© (CVS-Q) after their shift.
Results :
On Days 1, 7, 30, and 60, the TA [D] (mean ± standard deviation) was −5.89 ± 3.1 D, −5.77 ± 3.0 D, −5.65 ± 2.9 D, and −5.74 ± 2.9 D, respectively; the AP was 1.83 ± 1.4 D, 1.91 ± 1.4 D, 1.91 ± 1.5 D, and 1.81 ± 1.4 D and the AL was 69.2 ± 19.8%, 67.5 ± 21.7%, 68.5 ± 21.1%, and 69.0 ± 21.9%, respectively. None of the variables showed any significant changes. The CVS-Q score on each day was 1.65 ± 2.3, 1.70 ± 2.4, 1.70 ± 2.4, and 2.05 ± 2.6, respectively, showing a significant increase in the score (p < 0.05). EEG results showed a Stress of 34.6 ± 16 on Day 1 and 35.7 ± 17 on Day 60; a Calmness of 25.3 ± 2 and 28.6 ± 11, respectively; and a Comfortable of 54.4 ± 22 and 47.0 ± 19, respectively, indicating a significant decrease in comfort. The phoria showed a distance phoria of −0.7Δ on Day 1 and +0.1Δ on Day 60 and a near phoria of −3.4Δ and +1.25Δ, respectively, indicating an esophoric shift in near heterophoria (p < 0.05).
Conclusions :
SCL use for 60 days period had no effects on AL, TA, and AL, and little effect on the asthenopia and visual symptoms. Meanwhile, the esophoric shift at near is believed to be an increase in convergence associated with expansion of the near vision zone.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.