Comparison of Amplitude of Accommodation in Different Room Illumination while Using VDU as a Target

Abstract

illumination. Further, to associate AA among genders, age groups, race and refractive error for different levels of room illumination was not significant (p > 0.05). However, amplitude of accommodation between 15-21years and 22-28 years showed significant (p = 0.047) difference for the first room illumination. CONCLUSION:The illumination has no clinically significant effect on amplitude of accommodation. INTRODUCTIONSince 1972, research into the effects of the VDU on the eye expanded [1] . Due to technological advances, millions of people such as office worker and college students are using computers for prolonged hours. However, after prolonged uses of these visual display units, the symptoms reported were eyestrain, tired eyes, headache, blurred vision, irritation, burning sensation, redness, double vision, neck pain, backache which might caused by combination of individual visual problems, poor workplace conditions and improper work habits [2][3] . On top of that, eye related symptoms reported as the most common health problem among VDT users [4][5][6] . To measure amplitude of accommodation is one of the necessary part of an eye examination to find out optimal refractive corrections and to reduce the eye related symptoms when doing near work especially while using visual display unit as a target. In addition, accommodation was proven to have association with the symptom of visual fatigue and asthenopia while doing near work. Abnormality associated with accommodation such as accommodative insufficiency, accommodative infacility and lag of accommodation reported among video display terminal (VDU) users in Nepal [7] . Several other studies have shown that visual tasks using visual display unit (VDU) terminals may induce temporary effects in the Convenience sampling method applied. The data analysis carried out by using one way repeated measure ANOVA, to look into the changes in amplitude of accommodation in different illuminations (23 Lux, 17 Lux and 4 Lux). RESULT: 32 subjects' data analyzed. Amplitude of accommodation measured via minus-lens method. No significant change noted among three levels of room illumination (p > 0.05) with the mean difference of 0.222DS from the first room illumination to third room

Amplitude of Accommodation among Students of a Malaysian Private University as Assessed Using Subjective and Objective Techniques

“…This study showed no significant difference in AA among ethnicities (Chinese, Malay, and Indian) when using the push-up ( p = 0.539), pull-away ( p = 0.558), minus lens ( p = 0.622), and modified push up ( p = 0.950) methods and dynamic retinoscopy ( p = 0.566). This finding agrees with Majumder [13] that there was no significant difference ( p > 0.05) between the AA according to ethnicity in all three-room illuminations of 24, 17, and 4 lux. In another Malaysian-based study, Majumder and Ying [9] showed a significant difference ( p < 0.05) between the AA at 20-degree downgaze in Chinese and non-Chinese participants.…”

“…However, no significant difference was found for the minus lens ( p = 0.051) or modified push-up ( p = 0.216) technique. Majumder [13] reported no significant difference ( p > 0.05) in AA according to sex for any of the room illuminations ( p = 0.529, p = 0.459, and p = 0.302 for 23, 17, and 4 lux, respectively). In addition, Majumder and Ying [9] showed no significant difference in AA according to sex for all directions of gazes (p = 0.18, p = 0.18, p = 0.68, and p = 0.80) for primary gaze, 20 degrees up gaze, 20 degree downgaze, and 40 degrees downgaze, respectively.…”

“…In comparison, Momeni-Moghaddam et al [12] performed the minus lens technique at 40 cm with addition of the same 2.5 D. In another study, Mathebula et al [6] found that the mean AA for the push-up method (10.22 ± 1.67 D) was highest, followed by the pull-away (9.08 ± 1.44 D) and minus lens (8.43 ± 1.68 D) techniques and dynamic retinoscopy (6.58 ± 1.34 D), which correlates with the present study, even though their mean AA was lower than that here. Majumder [13] conducted a study in Malaysia and reported AA at different room illuminations for a Malaysian population whose age ranged from 22 to 29 years. The AA was measured using the minus lens technique for highest illumination (23 lux) and was determined to be 9.05 ± 0.58 D. However, the present study was conducted at an illumination of 400 lux, and the AA measured using the minus lens technique was 9.24 ± 1.18 D, which is higher due to the young-er age group, testing target, and variation in illumination; a measurement obtained using the minus lens technique at 33 cm and 3 D was added to compensate for the working distance [13].…”

“…Majumder [13] conducted a study in Malaysia and reported AA at different room illuminations for a Malaysian population whose age ranged from 22 to 29 years. The AA was measured using the minus lens technique for highest illumination (23 lux) and was determined to be 9.05 ± 0.58 D. However, the present study was conducted at an illumination of 400 lux, and the AA measured using the minus lens technique was 9.24 ± 1.18 D, which is higher due to the young-er age group, testing target, and variation in illumination; a measurement obtained using the minus lens technique at 33 cm and 3 D was added to compensate for the working distance [13]. In another Malaysian-based study, Majumder and Ying [9] found that the AA for an age group ranging from 18 to 26 years was 9.72 ± 1.77 D for primary gaze and 11.26 ± 1.82 D at a 20-degrees downgaze, which was higher than the present study findings (9.24 ± 1.18 D).…”

“…This test was performed monocularly. The patient was asked to view an N5 target at 33 cm to counteract the effect of minification induced by the minus lens when the target was placed at 40 cm [13]. A-minus spherical lenses were added to the distance correction in 0.25-D steps.…”