• Journal of Korean Ophthalmic Optics Society
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• v.11 no.4
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• pp.329-335
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• 2006

The aim of this study was to evaluate the relation between Asthenopia of near lateral phoria and fusional reserve and also to provide fundamental clinical data. A total of 97 subjects, aged between 17 and 35 years old, who had no strabismus, an eye trouble or whole body disease, were examined nacked visual acuity, corrected visual acuity, corrected diopter, phoria, fusional reserve tests from October of 2005 to July of 2006. We excluded 8 subjects for the following reasons: if they had an amblyopia affecting binocular vision or inaccurate data. After these exclusions, 87 subjects remained. The results were as follow. According to interview results was that in near works, exophoria and esophoria with asthenopia was 59.6%, 64.7%, and 52.6% respectively. The subjects who have exophoria of $0-6{\Delta}$ in the range of normal state was 19.1%. The subjects who have exophoria of $7{\Delta}$ over in the range of abnormal state was 80.9%. The fusional reserve was in inverse proportion to phoria. The fusional reserve was twice over of phoria were 30.3%, and twice under were 69.7%. The asthenopia complain persons were 33.9% with the twice over fusional reserve of phoria. The asthenopia no complain persons were 66.1% with the twice under fusional reserve of phoria. In conclusion, our research has shown conclusively that there is a link between asthenopia of lateral phoria and fusional reserve and we also find that fusional reserve must be examined when we prescribe for a patient who has phoria.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.661-666
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• 2013

The aim of this study was to evaluate the property of heterophoria and fusional reserve in Adults in Jeon-buk Area. We examined the corrected visual acuity, corrected refractive error, heterophoria and fusional reserve of 116 healthy myopes aged from 20 to 44 old who had no strabismus no ocular and phyisical diseases. Using Von Graefe test of horizontal heterophoria Measurement, we measured orthophoria(26.7%), exophoria(52.5%) and esophoria(20.7%) for at near distance. The subjects who had exophoria of 0-6${\Delta}$ in the range of normal state was 38.8%, while the subjects who had exophoria in the range of abnormal state was 61.2%. Reducing fusional reserve was associated with increasing phoria. We found a relationship between asthenopia and fusional reserve of heterophoria and considered that fusional reserve must be examined when we preserve for a patient with heterophoria. Furthermore, Gradient method AC/A ratio was found 4.03 and its relationship to refractive error could not be determined.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.101-106
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• 2018

We examined refractive error, the corrected visual acuity, phoria and fusional reserve of 114 healthy myopes and hyperopia who had no strabismus, no ocular and physical diseases. We evaluated the occurrence of asthenopia according to phoria and fusional reserve. 41 out of 114 subjects which exophoria was 69% and esophoria was 5.5%, orthophoria was 26% made a complaint against asthenopia. The subjects who had exophoria of $0-6{\Delta}$ in the range of normal state was 61.4%, while the subjects who had exophoria of $7{\Delta}$ or more in the range of abnormal state was 38.6%. Reducing fusional reserve was associated with increasing phoria. The fusional reserve twice or more than phoria were 27.2%, and twice or under were 72.8%. Futhermore, AC/A ratio for heterophoria was found from 1.0 to 12.6 and its relationship to asthenopia of phoria could not be determined.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.1
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• pp.37-43
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• 2013

Purpose: The present study was conducted to investigate whether the directions of eye movement in playing computer games for certain period affected the change of near point of convergence (NPC) and fusional reserve (FR) or not. Methods: Total 40 subjects in 20s who have the visual acuity of 1.0 or higher without any ocular disease and accommodative dysfunction were asked to successively play computer games. After the subjects were moving eyes in horizontal and vertical directions for 40 and 90 minutes, their horizontal fusional reserves, vertical fusional vergence and near point of convergence were measured. Results: The near point of convergence showed a tendency to be receded after computer gaming in the horizontal and vertical directions, and both of horizontal and vertical fusional reserves were significantly reduced. The range of declined fusional reserves and receded near point of convergence after computer gaming for 90 minutes was smaller than those after computer gaming for 40 minutes. The change of binocular vision was affected by the horizontal eye movement rather than the vertical movement when analyzed by the direction of eye movement. Conclusions: This study revealed that the change in FR and NPC was different along with dominant direction of eye movement during visual display terminal (VDT) tasks. Therefore, the adjustment of VDT working time is required to prevent the dysfunction of binocular vision according to the dominant direction of eye movement during VDT task.