To investigate the accommodative loads change needed to maintain binocular fusion in patients with intermittent exotropia (IXT).
Seventeen consecutive patients with basic IXT and 15 normal controls ...were recruited. The WAM-5500 autorefractor (GrandSeiko, Fukuyama, Japan) was used to measure refractive error (D) under binocular and monocular viewing conditions at 6 m, 50 cm, 33 cm and 20 cm. The difference between binocular and monocular refractive error (D) at each distance defined the change in the accommodative load. The changes in accommodative load were compared between IXT patients and normal controls. We also investigated the change in accommodative loads according to the fixing preference in patients with IXT.
In IXT patients, the mean angles of deviation were 20.2 ± 7.19 and 21.0 ± 8.02 prism diopters at 6 m and 33 cm, respectively. Under binocular viewing, the changes in accommodative loads of each eye in IXT patients were significantly higher at 50, 33 and 20 cm than those of normal controls (p < 0.05, all). The changes in accommodative loads of fixating and deviating eyes at 6 m were not significantly different between IXT patients and normal controls (p = 0.193, 0.155, respectively). The changes in accommodative loads of the fixating eye at each distance were not significantly different from those of the deviating eye in IXT patients (p > 0.05).
The changes of accommodative loads at near fixation increased more in IXT patients than they did in normal controls while maintaining binocular fusion.
To investigate whether three-dimensional (3D) images cause nearwork-induced transient myopia (NITM) more than 2D images and whether there is any difference between 3D images with crossed and ...uncrossed disparities in the development of NITM.
Twenty-five volunteers, enrolled in this study, watched 2D and 3D movies and read 3D texts with crossed and uncrossed disparities for 2 to 3 hours with spectacle correction. The viewing distance was 50 to 70 cm. The refractive error was measured before and after each visual task. If there was a myopic shift after a task, the refractive error was measured at 3-minute intervals until it was resolved. The changes in the refractive error and the amount of NITM were evaluated and compared.
The mean age of volunteers was 27.8 ± 2.87 years, and the mean refractive error before the visual tasks was -4.19 ± 2.87 diopters (D). Thirteen subjects (52%) showed NITM after watching a 2D movie, whereas 20 subjects (80%) had NITM after a 3D movie (P = 0.037). The mean extent of NITM was 0.36 ± 0.27 D after watching a 3D movie and 0.10 ± 0.28 D after a 2D movie (P = 0.002). The 3D text with crossed disparity significantly induced NITM (P < 0.001), but that with uncrossed disparity did not. There was a tendency for the NITM to persist longer after subjects watched a 3D movie than after a 2D movie.
Viewing 3D images with crossed disparity induced a greater degree of NITM than 2D images. These results suggest that the greater NITM induced by 3D images may have a greater effect on the development and progression of permanent myopia.
Watching three-dimensional (3D) images is known to induce ocular and non-ocular symptoms, such as eye discomfort, fatigue, headache, and nausea, which can be referred to as "3D asthenopia". This ...study investigated ophthalmic factors associated with 3D asthenopia.
One hundred fifteen volunteers, aged 18 to 55 years, were enrolled in this study. 3D images were shown to all volunteers with 3D high-definition television for 90 minutes. Subjects who felt eyestrain were assigned to the asthenopia group (14 subjects) and subjects without symptoms were assigned to the control group (22 subjects). Ophthalmic factors including visual acuity, refractive errors, interpupillary distance, intraocular pressure, tear break-up time, near point of accommodation, presence of strabismus, stereoacuity, and retinal abnormalities were evaluated and compared between the two groups.
Six subjects in the asthenopia group had exophoria and 1 subject in the control group had constant exotropia. None of these participants had previously noticed symptoms of strabismus. Only the presence of strabismus was significantly different between the groups (P = .008).
The presence of exophoria may be a risk factor for 3D asthenopia, and 3D television may induce asthenopia by exacerbating this latent problem.
Purpose
To evaluate the effect of interpupillary distance (IPD) on stereoacuity using 2 kinds of stereoacuity tests in a normal population.
Methods
The distance stereoacuities of 33 healthy ...volunteers with no evidence of ocular diseases were measured with the Frisby Davis distance (FD2) stereotest and a 3-dimensional monitor-based distance stereotest (distance 3-D stereotest). These 2 kinds of stereotests were repeated using horizontal periscopes to increase the IPD 2- and 3-fold in order to investigate the effect of IPD increase on stereoacuity.
Results
The mean age of the participants was 28.5 years (range 20–41 years). The mean logarithms of the individual minimum angle of stereodiscrimination (logMAS) were 1.04 ± 0.23 (range 0.70–1.48 logMAS) with the FD2 stereotest and 1.52 ± 0.19 (range 1.00–1.85 logMAS) with the distance 3-D stereotest. As the IPD increased 2- and 3-fold, the logMAS measured with the FD2 stereotest improved from 1.04 to 0.98 and 0.91 (
P
= 0.061 and
P
= 0.003), respectively, and those measured with the distance 3-D stereotest worsened from 1.52 to 1.73 and 1.85 (
P
< 0.001 and
P
< 0.001), respectively.
Conclusions
Changes in IPD measured with the FD2 stereotest exhibited opposite effects to those measured with the distance 3-D stereotest. This reflects what is known to happen in the real world, i.e., that stereoacuity improves as IPD increases.
This study presents a different colloidal silver (Ag)/polymer system where Ag nanoparticles are deposited uniformly onto surface-functional porous poly(ethylene glycol dimethacrylate-
...co-acrylonitrile) (poly(EGDMA-
co-AN)) microspheres. The formation and morphology of the composite microspheres were characterized from electron microscopy and X-ray diffraction analyses. The significance of the present report is that owing to the high affinity between Ag and nitrile group (CN) on the large surface of the microspheres, the Ag nanoparticles having a face-centered cubic phase were incorporated evenly into the deep pores of the microspheres with fine size and size distribution. In the preservation test, the Ag/poly(EGDMA-
co-AN) composite microspheres obtained showed an excellent anti-bacterial performance, elucidating a high applicability for a new preservative.
To evaluate the accuracy of IOL power calculation using adjusted corneal power according to the posterior/anterior corneal curvature radii ratio.
Nine hundred twenty-eight eyes from 928 reference ...subjects and 158 eyes from 158 cataract patients who underwent phacoemulsification surgery were enrolled. Adjusted corneal power of cataract patients was calculated using the fictitious refractive index that was obtained from the geometric mean posterior/anterior corneal curvature radii ratio of reference subjects and adjusted anterior and predicted posterior corneal curvature radii from conventional keratometry (K) using the posterior/anterior corneal curvature radii ratio. The median absolute error (MedAE) based on the adjusted corneal power was compared with that based on conventional K in the Haigis and SRK/T formulae.
The geometric mean posterior/anterior corneal curvature radii ratio was 0.808, and the fictitious refractive index of the cornea for a single Scheimpflug camera was 1.3275. The mean difference between adjusted corneal power and conventional K was 0.05 diopter (D). The MedAE based on adjusted corneal power (0.31 D in the Haigis formula and 0.32 D in the SRK/T formula) was significantly smaller than that based on conventional K (0.41 D and 0.40 D, respectively; P < 0.001 and P < 0.001, respectively). The percentage of eyes with refractive prediction error within ± 0.50 D calculated using adjusted corneal power (74.7%) was significantly greater than that obtained using conventional K (62.7%) in the Haigis formula (P = 0.029).
IOL power calculation using adjusted corneal power according to the posterior/anterior corneal curvature radii ratio provided more accurate refractive outcomes than calculation using conventional K.
Purpose
To investigate whether fundus autofluorescence (FAF) obtained using an ultra-wide field (UWF) fundus camera with an artificial opacity pattern can grade the degree of presbyopia and nuclear ...cataract.
Methods
Sixty eyes of 30 patients were enrolled in this prospective diagnostic study. The nuclear cataract (nuclear color/opalescence (NC/NO)) was graded according to the Lens Opacity Classification System III. The monocular near point of accommodation (NPA) was measured in eyes with NC3/NO3 or less. The mean gray value difference between the central 8 artificial opacity lesions and peripheral 8 artificial opacity lesions in the retinal AF was measured. The correlation between the mean gray value difference, NPA, and nuclear cataract grade was analyzed.
Results
The mean nuclear cataract grade of 60 eyes was 3.2 ± 1.6 and mean NPA of 37 eyes was 45.3 ± 16.1 cm. The mean gray value differences increased with increasing nuclear cataract grade (eyes with NC/NO grade 1, 53.3 ± 11.4; 2, 78.3 ± 13.6; 3, 95.2 ± 12.2; 4, 101.6 ± 11.9; 5, 109.0 ± 22.9; and 6, 121.1 ± 12.0;
p
< 0.001). The mean gray value difference was positively correlated with both the monocular NPA (
R
2
= 0.637;
β
coefficient = 1.009; 95% CI, 0.748 to 1.271;
p
< 0.001) and nuclear cataract grade (
R
2
= 0.661;
β
coefficient = 12.437; 95% CI, 10.097 to 14.778;
p
< 0.001).
Conclusions
The FAF camera with an artificial opacity pattern attached can be used to effectively diagnose the degree of presbyopia and nuclear cataract.
Anti-bone resorption properties of the Korean herbal formulation, Gami-Honghwain (HJ), which comprises
Carthamus tinctorius L. seed and hominis placenta, were investigated. We demonstrate that the ...production of PGE2 is inhibited by 20–100
μg/ml HJ in nontransformed osteoblastic cells (MC3T3-E1 cells), indicating that HJ inhibits PGE2 production. The effect of HJ on the proliferation and osteoblastic differentiation in MC3T3-E1 was also studied. HJ dose-dependently increased DNA synthesis (significant at 20–100
μg/ml), and increased alkaline phosphatase (ALP) and prolyl hydroxylase activities of MC3T3-E1 cells (20–100
μg/ml), while anti-estrogen tamoxifen eliminated the stimulation of proliferation and ALP activity of MC3T3-E1 which was induced by HJ. These results indicate that HJ directly stimulates cell proliferation and differentiation of osteoblasts. Also, when we assessed the effects of HJ on osteoblastic differentiation in MC3T3-E1, HJ enhanced ALP activity and mineralization in a dose- and time-dependent fashion. This stimulatory effect of the HJ was observed at relatively low doses (significant at 20–100
μg/ml and maximal at 100
μg/ml). Northern blot analysis showed that the HJ (60
μg/ml) increased in bone morphogenetic protein-2 as well as ALP mRNA concentrations in MC3T3-E1 cells. HJ (100
μg/ml) slightly increased in type I collagen mRNA abundance throughout the culture period, whereas it markedly inhibited the gene expression of collagenase-1 between days 15 and 20 of culture. These results indicate that HJ has anabolic effect on bone through the promotion of osteoblastic differentiation, suggesting that it could be used for the treatment of common metabolic bone diseases.