• Journal of Korean Ophthalmic Optics Society
• /
• v.17 no.1
• /
• pp.75-81
• /
• 2012

Purpose: The study tried to figure out accommodative changes by measuring accommodative response, appearing on the full vision correction and low vision correction, with both eyes open-view auto-refractometer (Nvision-K5001, Shin-nippon, Japan). Methods: It carried out objective and subjective refractions, targeting 79 college students (58 males and 21 females) aged between 20 and 30($21.14{\pm}2.00$), by measuring accommodative changes with fixation distance at 1.0 m for eyesight of 1.0 after full version correction. The distances of 5.0 m, 1.0 m, 0.50 m, 0.33 m and 0.25 m for eyesight of 0.8, 0.7 and 0.6 after low vision correction arbitrarily added plus lens were applied. Results: the shorter measure fixation distances were, the greater changes accommodative response showed a tendency in the state of both full vision correction and low vision correction(0.7). The state of full vision correction showed a greater change of accommodative response than that of low vision correction(0.7). Both right and left eyes showed low accommodative responses in the state of low vision correction(0.7) than that of full vision correction. As a result of analyzing accommodative response at an eyesight of 0.8, 0.7, and 0.6 after low vision correction, the poorer eyesight was the lower accommodative response. Conclusions: Low vision correction from a near distance is expected to avoid unnecessary accommodative response, make eyes relaxed and prevent accommodative function disorder.

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.1
• /
• pp.79-85
• /
• 2014

Purpose: This study investigated accommodative changes by measuring accommodative response, appearing on the normal and convergence insufficiency Group, by using both eyes open-view auto-refractometer (Nvision-K5001, shin-nippon, Japan). Methods: It carried out objective and subjective refractions, targeting 74 college students (54 males and 20 females) aged between 19 and 29 ($21.59{\pm}2.53$), spherical equivalent OD $-2.28{\pm}2.03$ D, OS $-2.18{\pm}2.01$ D, by measuring accommodative responses at full correction and under correction with plus lens +0.25, +0.50, +0.75 arbitrarily added. Results: In the group of normal and convergence insufficiency, the shorter fixation distances were, the greater accommodative lags showed. The group of convergence insufficiency showed the lesser changes of accommodative response than those of normal. But we found that the convergence insufficiency group had a little larger accommodative amplitude in the total fixation distances. The full correction of convergence insufficiency group and the under correction (+0.50 D) of normal were alike in the accommodative responses. We have also investigated that the correlation between accommodative responses and fixation distances was decreased steeply at the excessive low vision correction. Conclusions: Under correction (+0.50 D) in a near distance is expected to avoid unnecessary accommodative responses, make eyes relaxed and comfortable.

• Journal of Korean Ophthalmic Optics Society
• /
• v.11 no.3
• /
• pp.187-192
• /
• 2006

The purpose of this research was to measurement real accmmnodative response amount of emmetropia using both eyes open-view auto-refractometer. We classified 377(male 146, female 231)eyes showing good naked vision at least 1.0, with a spherical equivalent refraction of under ${\pm}0.50D$ and cylindercal refraction of under -0.75D, from 10 to 59(mean $25.8{\pm}12.4$) years into 5 groups with 10 year interval and analyzed change of the near astigmatism and accommodative response amount to distinction of age. Age comparison, total mean 1.47D, 10 years age group 1.63D, 20 years age group 1.57D, 30 years age group 1.71D, 40 years age group 0.97D, and 50 years age group 0.05D. It was no difference between 10 to 30 years age group, But it showed the decre8.se which is remarkable from above 40 years age group and it does not almost response from above 50 years age group. Sexual difference, the man appeared some highly in male(mean $26.4{\pm}12.3$ years) 1.56D m female(mean $26.4{\pm}12.3$) 1.43D. Near-astigmatism power change, mean +0.12D, 10 years age group +0.06D, 20 years age group +0.16D, 30 years age group +0.09D, 40 years age group +0.05D, and 50 years age group +0,06D. No significant difference of astigmatism powers among the an groups, but from all years age group the astigmatism power appeared more highly far-astigmatism than near-astigmatism. Near-astigmatism axis change in the far-astigmatism changes at under ${\pm}10^{\circ}$ 103 eyes, above ${\pm}10^{\circ}$ rotation clockwise direction 108 eyes, above ${\pm}10^{\circ}$ rotation counter-clockwise direction 101 eyes. It was analyzed near-astigmatism axis change.

• Journal of Korean Ophthalmic Optics Society
• /
• v.14 no.1
• /
• pp.121-125
• /
• 2009

Purpose: This study has been conducted to know the prevalence of anisometropia and corneal refraction, accommodative response of myopic anisometropia. Methods: The study subject were 67 persons who myopic anisometropia of at least 1.00D, from among 808 total subject without ophthalmic diseases history from age 5 to 89 and the test were used to examine with both eyes open-view autorefractometer (NvisionK-5001). Results: The case which anisometropia were 85(10.5%) persons and myopic anisometropia were 67(78.8%) persons among the anisometropia. Difference between higher myopic eye and lower myopic eye were -1.22D${\pm}$0.94 in spherical equivalent, -0.25D${\pm}$0.72 in accommodative response, 0.04D${\pm}$0.68 in corneal refraction. In addition, the same case of both eyes accommodative response were 33(49.3%) persons, the great case of lower myopic eye accommodative response were 25(37.3%) persons and the great case of higher myopic eye accommodative response were 9(13.4%) persons. Conclusions: Myopic anisometropia was not affected by corneal refraction and both eyes difference of spherical equivalent was less as compared with both eyes difference of accommodative response.

• Journal of Korean Ophthalmic Optics Society
• /
• v.10 no.4
• /
• pp.323-328
• /
• 2005

The purpose of this research was to measurement real Accommodative response amount using both eyes open-view autorefractometer. Compared each Accommodative response amount to distinction of sex, age, kind of ametropia, amount of astigmatism and kind of astigmatism. The subjects were 153 healthy men and women between the age of 20~80 years. Age comparison, 20 years 1.15D, 30 years 1.23D and above 40 years 0.60D. It was no difference between 20 to 30 years old. But, is decrescent remarkably above 40 years old. Ametropia examined by hypermetropia 1.78D, emmetropia 1.51D, low myopia 1.08D, middle myopia 0.72D, high myopia 0.643D. Myopia increased, Accommodative response amount was expose that decrease. Astigmatism examined by non astigmatism 1.13D, low astigmatism 1.12D, middle astigmatism 0.85D, high astigmatism 0.83D. Astigmatism increased, Accommodative response amount was expose that decrease. The sex and astigmatism type difference appeared with the fact that the result is not a difference.

• Journal of Korean Ophthalmic Optics Society
• /
• v.12 no.2
• /
• pp.25-36
• /
• 2007

We researched the change of astigmatism power when the fixation point moved from far distance to near distance. Astigmatism power was measured by using both eyes open-view auto-refractometer. We divided the ages between 5 and 67 years old into 12 groups with 1,598 healthy eyes(male-698 eyes and female-900 eyes) without eyes problems and experiences of eyes operations. The mean power in far astigmatism showed that with-the-rule of the total astigmatism: -0.79D, with-the-rule of the corneal astigmatism: -1.07D and against-the-rule of the residual astigmatism : -0.79D were found most respectively. The correlation between cornea astigmatism and total astigmatism was y=0.7493 x + 0.5661 r=0.6510, residual astigmatism and total astigmatism was y=0.248 x - 0.5926 r=0.2598 and corneal astigmatism and residual astigmatism was y=-0.4439 x - 0.1813 r=-0.5551 in the far distance. The mean power in near astigmatism showed that with-the-rule of total astigmatism : -0.92D, with-the-rule of corneal astigmatism : -1.12D, against-the-rule of residual astigmatism : -0.87D were found most respectively. In the near distance, The correlation between corneal astigmatism and total astigmatism was y=0.6872 x + 0.5934 r=0.6204, residual astigmatism and total astigmatism was y=0.303 x - 0.6066 r=0.3165, corneal astigmatism and residual astigmatism was y=-0.46 x - 0.0626 r=-0.5322. When the fixation point moved far distance to near distance, the differences of power according to the type of astigmatism were total astigmatism: $-0.07D{\pm}0.44D$, corneal astigmatism: $-0.04D{\pm}0.54D$ residual astigmatism:$0.01D{\pm}0.53D$. Most of astigmatism refractive power was increased except for oblique-the -astigmatism. When the fixation point moved far distance to near distance, the change of astigmatism refractive power showed total astigmatism: 540 eyes(33.7%), corneal astigmatism: 638 eyes(39.9%), residual: 841 eyes(52.6%).

• Journal of Korean Ophthalmic Optics Society
• /
• v.19 no.2
• /
• pp.217-224
• /
• 2014

Purpose: This study was conducted to compare and analyze the accommodative system (accommodative response and accommodative lag) according to the material and font size of near visual media that we often encounter in daily life. Methods: Forty adult men and women aged 20 to 30 who not had specific ocular diseases and refractive surgery experience were examined to measure and compare the accommodative response according to the material of near visual media (print paper, newspaper, magazine, the I-Phone, LCD monitor) and font size (6, 8, 10, 12) by using both eyes open-view auto-refractometer. Results: The accommodative stimulus was $2.28{\pm}0.11D$ and the accommodative response was $1.66{\pm}0.30D$. The accommodative lag namely the difference between accommodative stimulus and accommodative response was $0.62{\pm}0.28D$. The accommodative response according to material of visual media using LCD monitor was $1.35{\pm}0.26D$ (p=0.00) and using the I-Phone was $1.55{\pm}0.25D$ (p=0.04). Both of them were statistically significant lower. The accommodative lag using LCD monitor was $0.93{\pm}0.24D$ (p=0.00) and using the I-Phone was $0.73{\pm}0.25D$ (p=0.04) and they were statistically significant higher. The accommodative response and accommodative lag according to font size were not statistically significant (p>0.05). Conclusions: During near working, the accommodative system was more affected by material than font size of visual media. Especially, visual media of non-luminous material (print paper, newspaper, magazine) are considered fewer burdens on eyes than luminous material (I-Phone, LCD monitor) in terms of accommodative system.