New technology using crystalline lens autofluorescence for presbyopia and cataract grading.

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 (R2 = 0.637; ß coefficient = 1.009; 95% CI, 0.748 to 1.271; p < 0.001) and nuclear cataract grade (R2 = 0.661; ß 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.

Adhesion after Y-split procedure can affect its mechanism for treating overshoots in Duane's syndrome.

PURPOSE: To investigate the extent of adhesion and changes in the Y configuration after the Y-split procedure, compared with the posterior fixation suture. METHODS: Twelve New Zealand white rabbits were included in the study. The 10-mm Y-split procedure was performed in the superior rectus muscle (SR) of one eye, and the 10-mm posterior fixation suture was made in the SR of the other eye. Six weeks after surgery, the Y arm lengths and lengths of adherence to the sclera were measured. If the adhesion involved the whole Y arm, the distance between the original SR insertion and most proximal part of the adhered SR was measured. In the eyes with posterior fixation suture, the distance between the SR insertion and most proximal part of the adhered SR was evaluated. RESULTS: The average nasal and temporal Y arm lengths were 6.37 ± 0.65 and 6.54 ± 0.63 mm, respectively, a significant decrease from those measured immediately after surgery (P = 0.002 and 0.002, respectively). Adhesions involved the entire Y arms in 11 of 12 SRs (91.7%), with an average adhesion length of 7.01 ± 1.04 mm. In SRs with posterior fixation sutures, the average adhesion was 9.18 ± 0.62 mm from the insertion, which was only 2.17 mm posterior to proximal portion of adhesion in Y-split SR (P < 0.001). CONCLUSIONS: Healing process reduces the Y arm length. Adhesion may involve the entire Y arm and could weaken or alter the therapeutic mechanism after the Y-split procedure.

Effect of Ambient Light Exposure on Ocular Fatigue during Sleep.

BACKGROUND: To investigate the influence of nocturnal ambient light on visual function and ocular fatigue. METHODS: Sixty healthy subjects (30 men and 30 women) aged 19 through 29 years with no history of ocular disease were recruited. All subjects spent 3 consecutive nights in the sleep laboratory. During the first and second nights, the subjects were not exposed to light during sleep, but during the third night, they were exposed to ambient light, measuring 5 or 10 lux at the eye level, which was randomly allocated with 30 subjects each. The visual function and ocular fatigue were assessed at 7 a.m. on the 3rd and 4th mornings, using best-corrected visual acuity, refractive error, conjunctival hyperemia, tear break-up time, maximal blinking interval, ocular surface temperature, and subjective symptoms reported on a questionnaire. RESULTS: Three men and three women subjects failed to complete the study (4 in the 5 lux; 2 from the 10 lux). For the entire 54 subjects, tear break-up time and maximal blinking interval decreased (P = 0.015; 0.010, respectively), and nasal and temporal conjunctival hyperemia increased significantly after sleep under any ambient light (P < 0.001; 0.021, respectively). Eye tiredness and soreness also increased (P = 0.004; 0.024, respectively). After sleep under 5 lux light, only nasal conjunctival hyperemia increased significantly (P = 0.008). After sleep under 10 lux light, nasal and temporal conjunctival hyperemia, eye tiredness, soreness, difficulty in focusing, and ocular discomfort increased significantly (P < 0.05). CONCLUSION: Nocturnal ambient light exposure increases ocular fatigue. Avoiding ambient light during sleep could be recommended to prevent ocular fatigue.

Clinical exhibition of increased accommodative loads for binocular fusion in patients with basic intermittent exotropia.

BACKGROUND: To investigate the accommodative loads change needed to maintain binocular fusion in patients with intermittent exotropia (IXT). METHODS: 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. RESULTS: 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). CONCLUSION: The changes of accommodative loads at near fixation increased more in IXT patients than they did in normal controls while maintaining binocular fusion.

Stability of Y-splitting procedure combined with hang-back recession of the rectus muscle in rabbit eyes.

BACKGROUND: The Y-splitting procedure has been used both to treat up-shoots and down-shoots in Duane syndrome, and as a substitute for posterior fixation suture. The Y-split is often performed in conjunction with a hang-back recession when a large amount of recession or an adjustable suture is necessary. Herein, we evaluated the stability of Y-splitting hang-back recession in the rectus muscle. METHODS: Under general anesthesia, a 5-mm hang-back recession of the superior rectus muscle (SR) with Y-splitting was performed in ten eyes from ten rabbits (hang-back group). A conventional recession was performed in the SR of the fellow eye (control group). Six weeks after the procedure, the distance between the original insertion and the recessed SR (recession amount) and the width between the nasal and temporal halves of the SR were measured. These values were compared to the measurements taken at the time of surgery. RESULTS: The hang-back group had a significantly larger forward displacement than the control group (P < 0.001 for both the nasal and temporal halves). The width change between the nasal and temporal halves was also significantly larger in the hang-back group (4.94 ± 1.32 mm) than in the control group (1.14 ± 0.60 mm, P < 0.001). Additionally, the Y-configuration appeared to be more collapsed in the hang-back group than in the control group. CONCLUSION: Y-splitting of the rectus muscle may be unstable when it is combined with a hang-back recession. Surgeons should consider this possibility when performing Y-splitting procedures.

Effect of Classroom Illuminance on the Development and Progression of Myopia in School Children.

PURPOSE: To evaluate the effect of classroom illuminance on the development and progression of myopia in elementary school children. METHODS: The daylight factor, a ratio of inside and outside illuminance, was obtained in 50 elementary schools. The firstgrade students in the school with the lowest daylight (LD) factor (LD school, 145 subjects; 0.51%) and with the highest daylight (HD) factor (HD school, 147 subjects; 13.35%) were selected. A survey was conducted to evaluate parental myopia, the amount of near-work and outdoor activities. The refractive error and axial length (AL) were measured at initial and after 6 months. The spherical equivalent, AL, and the survey results were compared between the two schools. The mean AL of the emmetropic children was obtained, and all subjects were divided into two groups, more and less than mean AL. Changes in refractive errors and AL were also compared according to AL. RESULTS: The amount of change in spherical equivalent and AL after 6 months were not different between the two schools. Initial prevalence of myopia was high in the HD school. However, it became similar between the two schools after 6 months. The mean AL of 155 emmetropic children was 22.7 ± 0.63 mm. In the 185 children with AL ≥22.7 mm, there was no difference in the AL change between the two schools. However, the change in AL in 107 children with AL <22.7 mm was significantly larger in the LD school (0.19 mm) than that in the HD school (0.15 mm, p = 0.049). Parental myopia, near-work and outdoor activities were not different between the two schools. CONCLUSIONS: High classroom illuminance during the day reduced axial elongation in eyes of children with a shorter AL. Increase in classroom light level by permitting more sunlight can be a protective measure against the development of myopia.

The effect of botulinum toxin injection on the hang-back recession of rectus muscles.

BACKGROUND: Hang-back recession and botulinum toxin injection are performed as one treatment option for the correction of large angles of deviation. However, the effect of botulinum toxin on hang-back recession has not been thoroughly evaluated. The purpose of this study is to investigate the effect of botulinum toxin on the hang-back recession of extraocular muscles. METHODS: Under general anesthesia, 6-mm hang-back recession of the superior rectus muscle (SR) was performed in all eyes of 12 rabbits. Botulinum toxin (5 IU, 0.1 ml) was injected into the SR of one eye in each rabbit. The inferior rectus muscles (IR) of both eyes were excised to model severe paralysis. The distance between the superior limbus and the new insertion was measured immediately after the procedure and 3 months postoperatively. Changes in the location of the insertion were evaluated and compared between both eyes. RESULTS: After excision of the IR, upward deviation was observed in all eyes. The insertion site of the recessed SR immediately after the procedure and 3 months postoperatively were significantly different in all rabbit eyes with or without botulinum injection (P = 0.002, 0.002); SR advancement was observed in both cases. The amount of advancement was 1.38 ± 0.41 mm in the SR without botulinum toxin injection and 2.29 ± 0.45 mm in the SR with injection; this difference was statistically significant (P = 0.002). CONCLUSIONS: Botulinum toxin injection reduced the amount of hang-back recession in deviated rabbit eyes. Surgeons should be aware that botulinum toxin can diminish the effects of hang-back recession when used simultaneously.

Clinical factors affecting the rate of exodrift after surgery in patients with basic intermittent exotropia.

We investigated the period of postoperative exodrift during follow-up and clinical factors that affect the rate of exodrift after surgery in the patients with intermittent exotropia (IXT). A retrospective review of medical records of patients with exodrift who underwent bilateral rectus recession for IXT was performed. Exodrift was defined as angle of deviation greater than 10 prism diopters (PD) at distance and near. The median survival period of postoperative exodrift was analyzed using Kaplan Meier survival analysis. The patients were divided into two groups according to the median period of postoperative exodrift (early and late group). The weighted Cox's proportional hazards regression analysis to investigate the risk factors that affect rate of postoperative exodrift was performed. A total of 108 patients was included. The preoperative angle of deviation at distance and near were 30.3 ± 7.2 PD and 29.5 ± 8.6 PD, respectively. The median survival period of postoperative exodrift was 24 months (range, 6-48 months).The angle of deviation at postoperative day 1 in early and late group were - 3.8 ± 5.5 PD (range, - 16-8 PD) and - 7.7 ± 4.6 PD (range, - 16-4 PD) (p < 0.01). Minus value means esodeviation. In regression analysis, the angle of deviation at postoperative day 1 was the significantly related with rate of exodrift (p < 0.01). The median period of exodrift after surgery was 24 months, angle of deviation at postoperative day 1 could affect the rate of exodrift in patients with IXT.

Ultrastructural changes in myotendinous nerve endings induced by injection of botulinum toxin into the extraocular muscle.

BACKGROUND: The myotendinous nerve endings located in the extraocular muscles are considered as proprioceptors. The proprioception of extraocular muscles can be altered if botuminium toxin, which is widely used for the treatment of strabismus, damages the endings. The purpose of this study is to investigate the ultrastructural changes in myotendinous nerve endings after injection of botulinum toxin into the extraocular muscles. METHODS: Under general anesthesia, 5 IU of botulinum toxin (0.1 ml) were injected into the superior and medial rectus muscles of one eye in each of 12 cats, and 0.1 ml of normal saline was injected into the muscles of the other eye. The myotendinous junction was harvested in four cats each at 1, 4, and 12 weeks after injection and examined using electron microscopy. The myotendinous junctions of four normal uninjected cats were also examined as a control group. RESULTS: There were no morphological differences between the control group and saline injection group. In the botox injection group, separation of the myelin sheath and an increase in neurofilaments in axons of myelinated and unmyelinated nerve fibers were observed 1 week after injection and persisted until 12 weeks. Around the terminal nerve endings, incomplete Schwann cells with axonal exposure were observed, and fibroblast-like changes in Schwann cells were detected. These findings were not observed in the control group. CONCLUSIONS: Injection of botulinum toxin into the extraocular muscle induced ultrastructural changes in the myotendinous nerve endings. The possibility that those changes might diminish the proprioceptive abilities of the extraocular muscle should be considered when botulinum toxin is used for the treatment of strabismus.

Vertical Optokinetic Stimulation Induces Diagonal Eye Movements in Patients with Idiopathic Infantile Nystagmus.

Purpose: In patients with early ocular misalignment and nystagmus, vertical optokinetic stimulation reportedly increases the horizontal component of the nystagmus present during fixation, resulting in diagonal eye movements. We tested patients with infantile nystagmus syndrome but normal ocular alignment to determine if this crosstalk depends on strabismus. Methods: Eye movements were recorded in seven patients with infantile nystagmus. All but one patient had normal ocular alignment with high-grade stereopsis. Nystagmus during interleaved trials of right, left, up, and down optokinetic stimulation was compared with waveforms recorded during fixation. Six patients with strabismus but no nystagmus were also tested. Results: In infantile nystagmus syndrome, horizontal motion evoked a mostly jerk nystagmus with virtually no vertical component. A vertical optokinetic pattern produced nystagmus with a diagonal trajectory. It was not simply a combination of a vertical component from optokinetic stimulation and a horizontal component from the subject's congenital nystagmus, rather in six of seven patients, the slow-phase velocity of the horizontal component during vertical optokinetic stimulation differed from that recorded during fixation. In the six strabismus patients without nystagmus, responses to vertical optokinetic stimulation were normal. Conclusions: In patients with congenital motor nystagmus, a vertical noise pattern drives a diagonal nystagmus. This appears to arise because of crosstalk between the vertical and horizontal components of the optokinetic system. This abnormal response to vertical stimulation is not caused by strabismus because it occurs in patients with infantile nystagmus without strabismus. Moreover, it is absent in patients with strabismus and no spontaneous nystagmus.

Papilledema from gain-of-function mutations in the STAT3 gene.

BACKGROUND: Signal Transducer and Activator of Transcription 3 (STAT3) gain-of-function germline mutations are associated with diverse clinical manifestations, including autoimmune cytopenia, lymphadenopathy, immunodeficiency, endocrinopathy, and enteropathy. We describe a new feature: raised intracranial pressure with papilledema. MATERIALS AND METHODS: Report of two cases. RESULTS: The first patient had a de novo heterozygous c.2144C>T (p.Pro715Leu) mutation in the STAT3 gene. At age 1 she had papilledema with marked sheathing of the proximal vessels on the optic discs. Follow-up 8 years later showed chronic papilledema, cystoid macular edema, and vision loss. The second patient had a de novo heterozygous c.2147C>T (p.Thr716Met) mutation. At age 12 he developed papilledema, which recurred despite treatment. In both patients, repeated sampling of the cerebrospinal fluid demonstrated a lymphocytic pleocytosis. CONCLUSIONS: Papilledema can occur as a manifestation of STAT3 gain-of-function mutation, sometimes accompanied by prominent vascular sheathing and cystoid macular edema. The mechanism may be chronic meningeal infiltration by white blood cells, impairing cerebrospinal fluid absorption.

Esodeviation without correction for tapering hyperopia in refractive accommodative esotropia.

OBJECTIVE: To investigate clinical features for prescription of tapered hyperopia in patients with refractive accommodative esotropia (RAET). METHODS: The clinical features in patients with RAET who began tapering of hyperopia were analyzed. Within a range that can sustain corrected visual acuity and stereoacuity, patients were prescribed for tapered hyperopic correction by 0.25-diopters (D) interval, up to a maximum of 1.0 D. At every visit, visual acuity and esodeviation with and without correction, amount of tapered hyperopia, and near stereoacuity were measured. RESULTS: One hundred and six patients were enrolled in this study. The follow-up period was 3.1 ± 0.2 years and frequency of visits was 6.3 ± 0.6. Tapering hyperopia was initiated at 6.1 ± 2.9 years, and baseline refraction was 7.6 ± 1.5 D. The esodeviation without correction was 24.3 ± 8.5 prism diopters (PD), and median near stereoacuity was 400 arc sec. The median amount of tapered hyperopia at visit was 0.5 D. At the final visit, there were no significant deteriorations in visual acuity, esodeviation with correction, or near stereoacuity (p > 0.05, all). The amount of tapered hyperopia was positively correlated with correction and the reduced esodeviation without correction (p = 0.03). CONCLUSIONS: Esodeviation without correction should be considered for tapering hyperopia for patients with RAET. Esodeviation without correction can be easily measured, and its decline may be used as a clinical indicator for tapering hyperopia.

Use of the Posterior/Anterior Corneal Curvature Radii Ratio to Improve the Accuracy of Intraocular Lens Power Calculation: Eom's Adjustment Method.

Purpose: To evaluate the accuracy of IOL power calculation using adjusted corneal power according to the posterior/anterior corneal curvature radii ratio. Methods: 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. Results: 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). Conclusions: 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.

Consecutive esotropia in intermittent exotropia patients with immediate postoperative overcorrection more than 17 prism diopters.

PURPOSE: To report the incidence and the factors of consecutive esotropia (ET) in patients with immediate postoperative overcorrection of at least 17 prism diopters (PD) after surgery for intermittent exotropia (X(T)). METHODS: Four-hundred-five patients under the age of 18 were included in this study. They underwent bilateral lateral rectus recession (LROU-rec) or unilateral recession-resection (R&R) for X(T). On postoperative day one, the patients with at least 17 PD overcorrection were classified as group 1 and those with less than 17 PD as group 2. Age, refractive error, type of surgery, lateral incomitancy, and the incidence of consecutive ET were analyzed for each group. RESULTS: Group 1 consisted of 116 patients (28.6%) and group 2 consisted of 289 (71.4%). At the six-month follow-up visit, consecutive ET had developed in 16 patients (13.8%) in group 1, and in five patients (1.7%) in group 2 (p<0.001). The occurrence of consecutive ET was not related to age at the time of surgery (p=0.46 in group 1; p=0.54 in group 2), refractive error (p=0.18 in group 1; p=0.08 in group 2), or the type of surgery (p=0.69 in group 1; p=1.00 in group 2). The incidence in group 1 was 23.8% in patients with lateral incomitancy and 8.1% in patients without lateral incomitancy (p<0.05). In group 2, the incidence was 4.4% in patients with lateral incomitancy and 0.5% in patients without lateral incomitancy (p=0.04). CONCLUSIONS: Consecutive ET developed in 13.8% of patients with immediate overcorrection of at least 17 PD. Lateral incomitancy was the most important risk factor.

Clinical Features and Surgical Outcome of Triad Exotropia.

PURPOSE: To describe the clinical features and surgical outcome of A-pattern exotropia combined with dissociated vertical deviation and superior oblique overaction. METHODS: The medical records of patients with A-pattern exotropia combined with dissociated vertical deviation and superior oblique overaction who underwent horizontal muscle surgery alone or in combination with superior oblique muscle weakening surgery were retrospectively reviewed. The patients were divided into two groups according to their surgery: the horizontal muscle surgery alone group and the horizontal muscle surgery with bilateral superior oblique weakening surgery (combined surgery) group. The preoperative clinical features and postoperative surgical outcomes at the patients' final follow-up visits were analyzed. RESULTS: A total of 40 patients were included. The mean age at diagnosis was 5.5 ± 4.6 years. Amblyopia and latent nystagmus were observed in 18 (45%) and 10 (25%) patients, respectively. Six (15%) patients were associated with delayed development and hemiplegia. The mean angle of exodeviation was 27.7 ± 11.2 and 28.5 ± 10.9 prism diopters (PD) for distance and near, respectively. The mean degree of superior oblique overaction was 1.9 ± 1.1 and asymmetrical dissociated vertical deviation was observed in 24 (60%) patients. At the final follow-up visit, the horizontal angle of deviation was not significantly different between the groups. The success rates were 57.1% and 80% in the horizontal muscle surgery alone and combined surgery groups, respectively. These differences were statistically significant (P = .04). CONCLUSION: Amblyopia was common and the prognosis of binocularity was poor in triad exotropia. Some patients had neurological deficits. The surgical success rate in this study was variable, ranging from 57.1% to 80%. [J Pediatr Ophthalmol Strabismus. 2017;54(6):363-368.].

Visual Discomfort While Viewing Three-dimensional Television as a Screening Tool for Pediatric Eye Diseases in Children.

PURPOSE: To investigate the efficacy of evaluating 3D asthenopia and 3D perception difficulty for screening of binocular vision abnormalities in children. METHODS: Patients aged 6-12 years with abnormal binocularity, including strabismus, amblyopia, and anisometropia, were included. Age-matched normal subjects without any ophthalmologic abnormality other than a refractive error were also recruited. The best-corrected visual acuity, refractive error, angle of strabismus, and stereopsis were measured. Presenting visual acuity (PVA) was measured as the uncorrected visual acuity for subjects without glasses and spectacle-corrected visual acuity for those with glasses. After watching 3D TV for 30 min, a survey was administered to evaluate the 3D perception and 3D asthenopia. Receiver operation characteristic (ROC) curve analysis was conducted to evaluate the efficacy of the survey for detecting abnormal binocularity and poor PVA. RESULTS: One hundred subjects were enrolled in this study. Among them, 59 had abnormal binocularity (strabismus, anisometropia, or amblyopia), and 41 were normal control. Among the entire subjects, the number of subjects with a PVA of 20/40 or worse in one or both eyes was 24 (7 from the normal control and 17 with abnormal binocularity). ROC curve analysis revealed that the survey did not effectively detect strabismus, anisometropia, or amblyopia. However, for detection of PVA 20/40 or worse in the subjects with abnormal binocularity, the total score of the survey yielded an area of 0.714 under the ROC curve (p = 0.010). The sensitivity was 88.2% and specificity was 61.9% with a cutoff at 0.50. CONCLUSION: The degree of 3D asthenopia and 3D perception while watching 3D TV were not effective for screening of abnormal binocularity. However, evaluation of the severity of 3D asthenopia and the quality of 3D perception can help screen of decrease in PVA that requires correction.

Prevalence and Factors Associated with the Use of Eye Care Services in South Korea: Korea National Health and Nutrition Examination Survey 2010-2012.

PURPOSE: To estimate the factors and prevalence of eye care service utilization in the South Korean population. METHODS: This cross-sectional, population-based study included data from 22,550 Koreans aged ≥5 years who participated in the Korea National Health and Nutrition Examination Survey from 2010 to 2012. For people aged 5 to 11 years (young children), information was based on self-reports of contact with eye care service in the past year; for people aged ≥12 years (older population), the information was based on the self-reported lifetime contact with eye care service. Univariate and multivariate logistic regression analyses of the complex sample survey data were performed. RESULTS: The prevalence of eye care service use in young children during the past year was 61.1% (95% confidence interval, 58.1%-64.1%), while that in the older population during their lifetime was 73.5%. Subjects aged 7 to 11 years were more likely to have had an eye examination in the past year than subjects aged 5 to 6 years (odds ratio, 3.83; 95% confidence interval, 2.37-6.19). Multivariate logistic regression analysis indicated that higher monthly household income, being a National Health Insurance holder, and having private health insurance were related to more frequent use of eye care services in young children. For the older population and women, those living in an urban area and those with a best-corrected visual acuity less than 20 / 40 in the worse-seeing eye were more likely to have had an eye examination during their lifetime. Low education level was associated with low lifetime use of eye care services in the older population. CONCLUSIONS: There are sociodemographic disparities with use of eye care services in South Korea. This population-based study provides information that is useful for determining different intervention programs based on sociodemographic disparities to promote eye care service utilization in South Korea.

Vision Improvement with Refractive Correction Does Not Completely Exclude Major Eye Diseases: Analyses of Visually Impaired South Korean Population in the Korea National Health and Nutrition Examination Survey 2009-2011.

PURPOSE: To investigate the association between vision improvement with refractive correction in the visually impaired eyes and the prevalence of ocular comorbidities in the South Korean population. MATERIALS AND METHODS: The data of 24,620 individuals in the Korea National Health and Nutrition Examination Survey (KNHANES 2009-2011) were reviewed. Visual impairment was defined as a presenting visual acuity < 20/60. The participants with visual impairment in at least one eye were divided into 3 groups according to the best-corrected visual acuity (group 1: <20/30, group 2: ≥20/30 but <20/25, and group 3: ≥20/25). The prevalence of ocular comorbidities was estimated and compared between the three groups. RESULTS: Visual impairment in at least one eye was found in 3031 individuals. Groups 1, 2, and 3 comprised 23.5%, 22.2%, and 54.3% of these visually impaired eyes, respectively. The prevalence of cataract, diabetic retinopathy, age-related macular degeneration, corneal opacity, blepharoptosis, and pterygium was similar to or even higher in group 2 compared to group 1. The prevalence of glaucoma and age-related macular degeneration was 5.40% and 11.39%, respectively, in group 2 and 3.31% and 3.76%, respectively, in group 3. CONCLUSIONS: Appropriate ophthalmologic examination is necessary even if people exhibit vision improvement after optical correction.

Effects of Head-Mounted Display on the Oculomotor System and Refractive Error in Normal Adolescents.

PURPOSE: To investigate the clinical effects of head-mounted display on the refractive error and oculomotor system in normal adolescents. METHODS: Sixty volunteers (age: 13 to 18 years) watched a three-dimensional movie and virtual reality application of head-mounted display for 30 minutes. The refractive error (diopters [D]), angle of deviation (prism diopters [PD]) at distance (6 m) and near (33 cm), near point of accommodation, and stereoacuity were measured before, immediately after, and 10 minutes after watching the head-mounted display. The refractive error was presented as spherical equivalent (SE). Refractive error was measured repeatedly after every 10 minutes when a myopic shift greater than 0.15 D was observed after watching the head-mounted display. RESULTS: The mean age of the participants was 14.7 ± 1.3 years and the mean SE before watching head-mounted display was -3.1 ± 2.6 D. One participant in the virtual reality application group was excluded due to motion sickness and nausea. After 30 minutes of watching the head-mounted display, the SE, near point of accommodation, and stereoacuity in both eyes did not change significantly (all P > .05). Immediately after watching the head-mounted display, esophoric shift was observed (0.6 ± 1.5 to 0.2 ± 1.5 PD), although it was not significant (P = .06). Transient myopic shifts of 17.2% to 30% were observed immediately after watching the head-mounted display in both groups, but recovered fully within 40 minutes after watching the head-mounted display. CONCLUSIONS: There were no significant clinical effects of watching head-mounted display for 30 minutes on the normal adolescent eye. Transient changes in refractive error and binocular alignment were noted, but were not significant. [J Pediatr Ophthalmol Strabismus. 2016;53(4):238-245.].