Purpose. To investigate the association between refractive error and common binocular vision and accommodative dysfunctions in Chinese adults and to report the percentage of these disorders in this sample population. Methods. This was a single-site, prospective cross-sectional clinic-based study. A total of 415 Chinese participants aged between 21 and 38 years were grouped into 4 refractive error groups (emmetropia, low, moderate, and high myopia) based on the spherical equivalent power of noncycloplegic refraction. Baseline testing including binocular vision and accommodative testing was performed on all eligible participants. A multiple-sign classification system was used to analyze these data for the diagnosis of common nonstrabismic binocular vision and accommodative dysfunctions. Associations between the diagnosis and refractive error groupings were examined by the chi-square test for the linear trend. Results. Associations with refractive error groupings were found for convergence insufficiency (p=0.008, r = −0.13) and divergence insufficiency (p=0.008, r = 0.131). The 3 most common dysfunctions in this sample population were basic exophoria (10.8%), convergence insufficiency (9.6%), and divergence insufficiency (7.0%). Approximately 40% of the sample population demonstrated at least one type of binocular vision dysfunction. Conclusion. Convergence insufficiency and divergence insufficiency were associated with refractive error groupings. Binocular vision dysfunction was a common finding in this sample population.

Background: The physical process of axial length growth among children and its role in the occurrence of myopia remain insufficiently explored. In this study, we investigate the patterns of ocular axial growth among persistent myopia (PM) and persistent non-myopia (PNM) children aged 3 to 15 years. Methods: A group of 6353 children aged 3 to 15 years, selected from rural schools in China, were followed up annually for 2 years. Biometric measurements including axial length (AL) and spherical equivalent refraction (SER) were obtained. Body height was recorded. Children were divided into two groups: PM group defined as SER of −0.50 D or less; PNM group defined as −0.50 D < SER < +3.0 D during follow-up. Results: Annual AL growth was fairly consistent for PNM eyes of children aged 3 to 11 years and then reduced significantly (independent t test, p < 0.001) for children aged 12 years and older. This pattern of AL changes was similar for PM children, although the AL growth was greater among them. Among children aged 6 and older, body height change was concomitant to AL growth (p < 0.01) and SER myopic shift (p < 0.001) until reaching 12 years old (p = 0.308 and p = 0.679, respectively). Conclusions: Stature growth and AL growth are both remarkable and consistent and concomitant but start to attenuate when the children reach 10 to 12 years old among emmetropic children. This observation suggests that AL growth is driven by physical development until 12 years old, whereas its excessive growth is dominated by myopia development.

Purpose: To report baseline information for a medical university cohort with the aim of exploring related factors for adult myopic progression. Methods: This study included Chinese freshmen students from a medical school in Guangzhou, China. All participants underwent detailed eye examinations, including cycloplegic refraction, ocular biometry and swept source optical coherence tomography. Choroidal thickness (CT) measurements were performed at nine locations in the macular area. Eye care habits and physical activities were measured by questionnaire. Results: The mean age of the study population (N = 307) was 18.8 ± 2.3 years, and 46.3% were male. The prevalence of myopia and high myopia was 92.8% and 21.1%, respectively. In emmetropia (spherical equivalent, SE −0.49D to +0.5D), mild to moderate myopia (SE −0.50D to −5.99D) and high myopia groups (SE <-6.00D), the average subfoveal CT was 300.3 ± 62.1 μm, 219.3 ± 65.4 μm and 194.0 ± 59.7 μm, respectively. In all eyes, the temporal CT was the thickest among all of the locations in the macular area, and the CT was thinnest nasally. Gender, axial length (AL), anterior chamber depth (ACD) and intraocular pressure (IOP) were the strongest related factors for subfoveal CT in mild to moderate myopia, while AL was the only significant determinant for subfoveal CT in highly myopic eyes. Conclusions: The prevalence of myopia was high in Chinese medical students. Macular CT was generally thinner in highly myopic eyes. Our study provided baseline information for the medical school cohort, including CT, AL, ACD, IOP and eye care habits.

Introduction. We evaluated the effectiveness of office-based accommodative/vergence therapy (OBAVT) with home reinforcement to improve accommodative function in myopic children with poor accommodative response.Methods. This was a prospective unmasked pilot study. 14 Chinese myopic children aged 8 to 12 years with at least 1 D of lag of accommodation were enrolled. All subjects received 12 weeks of 60-minute office-based accommodative/vergence therapy (OBAVT) with home reinforcement. Primary outcome measure was the change in monocular lag of accommodation from baseline visit to 12-week visit measured by Shinnipon open-field autorefractor. Secondary outcome measures were the changes in accommodative amplitude and monocular accommodative facility.Results. All participants completed the study. The lag of accommodation at baseline visit was 1.29 ± 0.21 D and it was reduced to 0.84 ± 0.19 D at 12-week visit. This difference (−0.46 ± 0.22 D; 95% confidence interval: −0.33 to −0.58 D) is statistically significant (p<0.0001). OBAVT also increased the amplitude and facility by 3.66 ± 3.36 D (p=0.0013; 95% confidence interval: 1.72 to 5.60 D) and 10.9 ± 4.8 cpm (p<0.0001; 95% confidence interval: 8.1 to 13.6 cpm), respectively.Conclusion. Standardized 12 weeks of OBAVT with home reinforcement is able to significantly reduce monocular lag of accommodation and increase monocular accommodative amplitude and facility. A randomized clinical trial designed to investigate the effect of vision therapy on myopia progression is warranted.