Amblyopia is defined as the reduction of best-corrected visual acuity of one or both eyes caused by conditions that affect normal visual development. The basic strategy to treat amblyopia is to obtain a clear retinal image in each eye and correct ocular dominance through forced use of the amblyopic eye. Treatment modalities include correcting any underlying organic disease, prescribing appropriate optical correction, and providing occlusion/penalization therapy for the non-amblyopic eye. Given the success of amblyopia treatment declines with increasing age, the detection and management of amblyopia should begin as early as possible during the sensitive period for visual development. Proper management of amblyopia during childhood can reduce the overall prevalence and severity of visual loss. This study aims to provide an update for the management of childhood amblyopia to provide better visual outcomes.
Amblyopia ; Dominance, Ocular ; Prevalence ; Retinaldehyde ; Visual Acuity

PURPOSE: To investigate the relationship between dominant eye and refractive error in patients with myopic anisometropia. METHODS: This study population consisted of myopes less than 15 years old who were followed up for anisometropia defined as interocular difference of spherical equivalent (SE) ≥1.0 diopter (D). All patients underwent the hole-in-the-card test at far and near to determine ocular dominance. The data were analyzed for statistical significance using Fisher's exact test. RESULTS: A total of 102 eyes in 51 patients were analyzed. The mean age of the patients was 10.4 ± 1.4 years and 54.9% were male. The mean SE was −2.97 ± 1.95 D in the right eye and −3.02 ± 1.92 D in the left eye. The right eye was the dominant eye in 43.1% and 37.3% at distance and near, respectively. The agreement of dominancy between distant and near was 82.4%. The near dominant eyes showed statistically significant accordance with more myopic eyes (p = 0.009). On the other hand, there was no statistically significant relationship between more myopic eyes and distant dominant eyes (p = 0.09). CONCLUSIONS: The near dominant eye was more myopic eye in patients with myopic anisometropia. This was considered to be related with the lag of accommodation in dominant eye with near distance.
Anisometropia ; Dominance, Ocular ; Hand ; Humans ; Male ; Myopia ; Refractive Errors

PURPOSE: The purpose of this study was to evaluate whether eye dominance changes after conventional pseudophakic monovision, and to identify factors that affect changes in eye dominance. METHODS: This retrospective study included 70 patients who underwent bilateral conventional monovision cataract surgery. Patients were divided into two groups based on whether they experienced a change in the dominant eye. We compared patients' uncorrected distance visual acuity (UCDVA), uncorrected near visual acuity (UCNVA), best-corrected visual acuity (BCVA), spherical equivalent, stereopsis, and time interval between cataract surgeries. RESULTS: The mean age was 71.26 ± 10.84 (range, 25–90) years, mean interval between surgery in each eye was 118.46 ± 183.50 (range, 17–1,018) days, and mean postoperative diopter difference was 1.16 ± 0.53 (range, 0.00–2.75) diopters. After bilateral cataract surgery, 22 patients (31.43%) experienced a change in eye dominance, whereas 48 patients (68.57%) experienced no change. There were no differences in the time interval between cataract surgeries, preoperative UCDVA and UCNVA, pre- and postoperative BCVA, or stereopsis in either group. Patients who experienced a change in eye dominance showed smaller differences between preoperative and postoperative spherical equivalent, compared with patients who experienced no change in eye dominance (t-test, p < 0.05). CONCLUSIONS: Twenty-two (31.43%) patients whose nondominant eyes were targeted for near vision showed altered eye dominance after conventional monovision cataract surgery. Eye dominance shows greater plasticity in patients with smaller differences between preoperative and postoperative spherical equivalent.
Cataract ; Clinical Study ; Depth Perception ; Dominance, Ocular ; Humans ; Plastics ; Presbyopia ; Retrospective Studies ; Visual Acuity

PURPOSE: To measure and analyze ocular deviations between dominant and non-dominant eyes using video-oculography (VOG) in intermittent exotropia. METHODS: Fourteen subjects who were diagnosed with intermittent exotropia from July 2017 to July 2018 with age of 5 or more, visual acuity of 20/30 or better and corrected visual acuity of 20/25 or more and difference in vision of both eyes of 1 line or less on Snellen optotype were included. The subjects were asked to fixate on a black-on-white optotype at 1 m, which subtended a visual angle of 50 minutes of arc. The video files and data about ocular deviations were obtained using VOG with alternate cover test. We analyzed angles of ocular deviations in dominant and non-dominant eyes. RESULTS: Among the 14 subjects in this study, the mean age were 7.6 ± 1.7 (range 5–9 years). Seven of 14 subjects had the right eye dominance. Six of the 14 subjects were men. There was no significant difference of ocular deviations between the dominant and non-dominant eyes in VOG (p = 0.167). Additionally, there was no significant difference of the values of VOG when one eye was exodeviated or re-fixated (p = 0.244), when both eyes were deviated, and when both eyes were re-fixated (p = 0.195, 0.637). CONCLUSIONS: In this study, there was no significant difference of ocular deviations between the dominant and non-dominant eyes, between when an eye was exodeviated or fixated using VOG. Therefore, it may not be a problem even if alternate prism cover test is performed in any eye in intermittent exotropia of more than 50 prism diopter without amblyopia or refraction abnormality that could affect the uncorrected visual acuity.
Amblyopia ; Dominance, Ocular ; Exotropia ; Humans ; Male ; Strabismus ; Visual Acuity

PURPOSE: To evaluate differences between dominant and non-dominant eyes by analyzing angle kappa in dominant and non-dominant eyes. METHODS: Fifty-seven subjects who had best corrected visual acuity 20/20 in the better-seeing eye and no underlying ocular disease were recruited. Ocular dominance was determined using the hole-in-the-card test. Corneal topography, refractive error, intraocular pressure (IOP), and axial length were evaluated in both eyes. RESULTS: On corneal topography examination, the angle kappa and white-to-white measurements were significantly smaller in the dominant eye than the non-dominant eye (p = 0.013 and p = 0.045, respectively). However, no significant differences in sim K's' astigmatism (p = 0.210), central corneal thickness (p = 0.533), and anterior chamber depth (p = 0.216) were observed. In addition, cylindrical powers of the subjects measured by autorefraction (AR) were significantly lower in the dominant eye (p = 0.026); however no differences in spherical equivalent measured by AR (p = 0.061), IOP measured using pneumonic tonometer (p = 0.536), or axial length measured using laser biometry (p = 0.093) were observed. CONCLUSIONS: In this study, we found the angle kappa a new factor in determining the dominant and non-dominant eye. Difference in axial length and spherical equivalent between dominant and non-dominant eye may be associated with the difference in angle kappa.
Anterior Chamber ; Astigmatism ; Biometry ; Corneal Topography ; Dominance, Ocular ; Intraocular Pressure ; Refractive Errors ; Visual Acuity

PURPOSE: To evaluate the anatomical difference between the dominant and nondominant eyes in healthy, young adults by measuring macular, peripapillary retinal nerve fiber layer (PRNFL), and macular ganglion cell layer (MGCL) thicknesses. METHODS: Two hundred healthy adults were recruited and assessed for ocular dominance using 'a hole in the card test'. PRNFL, macular and MGCL thicknesses of both eyes were measured using spectral domain optical coherence tomography (OCT). RESULTS: There were no statistically significant differences for average thicknesses of MGCL in each of the six areas between the dominant and nondominant eyes. No difference was observed between temporal, inferior, average PRNFL thickness and macular thickness in dominant and nondominant eyes. CONCLUSIONS: There was no intraocular anatomical difference between the dominant and nondominant eyes in healthy, young adults.
Adult ; Dominance, Ocular ; Ganglion Cysts ; Humans ; Nerve Fibers ; Retinaldehyde ; Tomography, Optical Coherence ; Young Adult

PURPOSE: To evaluate the association between ocular dominance, hand dominance and eye deviation in orthophoric and strabismus patients under general anesthesia during surgery. METHODS: The subjects were divided into 2 groups. Group 1 was composed of 38 patients who underwent strabismus surgery and group 2 was composed of 107 patients who underwent non-strabismus surgery under general anesthesia. Best corrected visual acuity (BCVA), dominant hand and fixating eye were obtained before surgery, and ocular dominance was assessed using the hole-in-the-card test. Under general anesthesia, we took a digital photo of both eyes, and the deviating eye was determined. RESULTS: Under general anesthesia, the deviated eye showed no statistically significant correlation to the dominant eye and dominant hand in group I, respectively (p = 0.61, 0.74, respectively). In group II, there was no correlation between the deviated eye and the dominant eye (p = 0.65). The deviated eye also showed no correlation to the dominant hand in group II (p = 0.61). CONCLUSIONS: There was no correlation between the dominant and deviated eye under general anesthesia in the strabismus surgery group and the non-strabismus surgery group. Also, there was no correlation between the dominant hand and the deviated eye in patients under general anesthesia in the 2 groups.
Anesthesia, General* ; Dominance, Ocular ; Hand* ; Humans ; Strabismus ; Visual Acuity

PURPOSE: To investigate the comparison of retinal nerve fiber layer (RNFL) thickness and optic disc parameters measured by optical coherence tomography (Cirrus HD-OCT(R)) in dominant and non-dominant eyes. METHODS: Seventy-one subjects without underlying ocular disease were recruited for the present study. Ocular dominance was determined using the hole-in-the-card test. Comprehensive standardized eye examinations were performed. Scans of the optic disc and RNFL were performed using OCT. RESULTS: The mean intraocular pressure (IOP) of the dominant eye was higher than its counterpart (p = 0.025). No significant differences were observed in uncorrected visual acuity, refractive error and axial length between dominant and non-dominant eyes (p = 0.235, 0.180, 0.850). No RNFL and optic disc features were identified in the dominant from non-dominant eyes. CONCLUSIONS: Although dominant eyes tended to have higher IOP than non-dominant eyes, no consistent ocular structural differences between dominant and non-dominant eyes with the use of OCT were found.
Dominance, Ocular ; Eye ; Intraocular Pressure ; Nerve Fibers ; Refractive Errors ; Retinaldehyde ; Tomography, Optical Coherence ; Visual Acuity

Synaptic long-term potentiation (LTP) and long-term depression (LTD) have been studied as mechanisms of ocular dominance plasticity in the rat visual cortex. Serotonin (5-hydroxytryptamine, 5-HT) inhibits the induction of LTP and LTD during the critical period of the rat visual cortex (postnatal 3~5 weeks). However, in adult rats, the increase in 5-HT level in the brain by the administration of the selective serotonin reuptake inhibitor (SSRI) fluoxetine reinstates ocular dominance plasticity and LTP in the visual cortex. Here, we investigated the effect of 5-HT on the induction of LTP in the visual cortex obtained from 3- to 10-week-old rats. Field potentials in layer 2/3, evoked by the stimulation of underlying layer 4, was potentiated by theta-burst stimulation (TBS) in 3- and 5-week-old rats, then declined to the baseline level with aging to 10 weeks. Whereas 5-HT inhibited the induction of LTP in 5-week-old rats, it reinstated the induction of N-methyl-D-aspartate receptor (NMDA)-dependent LTP in 8- and 10-week-old rats. Moreover, the selective SSRI citalopram reinstated LTP. The potentiating effect of 5-HT at 8 weeks of age was mediated by the activation of 5-HT2 receptors, but not by the activation of either 5-HT1A or 5-HT3 receptors. These results suggested that the effect of 5-HT on the induction of LTP switches from inhibitory in young rats to facilitatory in adult rats.
Adult ; Aging ; Animals ; Brain ; Citalopram ; Critical Period (Psychology) ; Depression ; Dominance, Ocular ; Fluoxetine ; Humans ; Long-Term Potentiation ; N-Methylaspartate ; p-Chloroamphetamine ; Plastics ; Rats ; Receptors, Serotonin, 5-HT3 ; Serotonin ; Visual Cortex

OBJECTIVE: To assess the effect of dominant and non-dominant vision in controlling posture in quiet stance. METHOD: Twenty-five healthy elderly subjects aged over 60 years old and twenty-five young subjects aged under 30 years old were assessed by computerized dynamic posturography. Postural stability was measured in two conditions; dominant eye open and non-dominant eye open. We used the sensory organization test (SOT) for evaluating sensory impairment. A SOT assessed the subject's ability to use and integrate somatosensory input, vision, and vestibular cues effectively to maintain balance. The SOT was conducted 3 times, and the average value of the 3 trials was used for data analysis. Equilibrium scores reflected the subject's anteroposterior sway. The highest possible score was 100, which indicated that the subject did not sway at all, and a score of 0 indicated a fall from the footplate. Determination of ocular dominance was performed by a hole-in-the card test. RESULTS: For the twenty-five young subjects in this study, equilibrium score in two conditions did not differ. However, for elderly subjects over 60 years, the equilibrium score in dominant vision was higher than in nondominant vision (p<0.05). CONCLUSION: In young subjects, there were no significant differences in postural control between dominant vision and non-dominant vision. However, in elderly subjects, postural control in non-dominant vision was significantly impaired. Therefore, the evaluation of a dominant eye should be considered in rehabilitation programs for elderly people.
Aged ; Cues ; Dominance, Ocular ; Eye ; Humans ; Posture ; Statistics as Topic ; Vision, Ocular