SIGNIFICANCE The prevalence of myopia and use of electronic displays by children has grown rapidly in recent years. We found that children viewing electronic displays, however, experience hyperopic defocus levels similar to those previously reported for other stimuli. PURPOSE This study aimed to compare accommodative behavior of nonmyopic and myopic children viewing a computer screen or mobile phone. METHODS Accommodative behavior was examined in 11 nonmyopic and 8 myopic children (11.32 ± 2.90 and 14.13 ± 2.30 years, respectively; P = .04; refractions, +0.51 ± 0.51 and −2.54 ± 1.29, respectively) using an open-field autorefractor (Grand Seiko) at target vergences from −0.25 to −5.95 D. Different size (scaled or nonscaled) and type (text or movie) stimuli were presented on an LCD monitor (distant) or an iPhone (near), with subjects viewing monocularly or binocularly in an illuminated or dark room. RESULTS At the typical reading distances (16.8 and 29.8 cm), all 19 children exhibited some amount of accommodative lag. Stimulus type had little impact on accommodation. However, slightly but statistically significant lower slopes were observed (Bonferroni-corrected significance level of P ≤ .01) for low room lighting (0.80 vs. 0.76; t test, t = 3.88; P = .003), nonscaled targets (0.83 vs. 0.77; t test, t = 4.28; P = .001), and monocular viewing (0.83 vs. 0.74; t test, t = 4.0; P = .002) in the nonmyopic group only. When viewing nonscaled stimuli binocularly (natural viewing), the means and standard deviations of accommodative lags (averaged across room lights on and off, and text and movie) were generally larger for the nonmyopes at all distances and were largest at 16.8 cm (1.31 ± 0.32 D for the nonmyopes and 1.11 ± 0.35 for the myopes; t test, t = 2.62; P = .01). CONCLUSIONS Generally small (mostly <1.00 D) amounts of hyperopic defocus are present in children binocularly viewing handheld electronic devices (nonmyopes slightly more than myopes). Modern electronic devices do not expose children to unusually high levels of hyperopic defocus.

To develop an optical model of a child's eye to reveal the impact of target distance and accommodative behaviour on retinal image quality when fitted with multi-zone lenses.Methods: Pupil size, aberration levels and accommodative lag were adjusted for models viewing stimuli at 400, 100, 33 and 20 cm. Distributions of defocus across the pupil and simulated retinal images were obtained. An equivalent 16-point letter was imaged at near viewing distances, while a 0.00 logMAR (6/6) letter was imaged at 400 cm. Multi-zone lenses included those clinically utilised for myopia control (e.g., dual-focus, multi-segmented and aspherical optics). Results:Viewing distance adjustments to model spherical aberration (SA) and pupil radius resulted in a model eye with wider defocus distributions at closer viewing distances, especially at 20 cm. The increasing negative SA at near reduced the effective add power of dual-focus lenses, reducing the amount of myopic defocus introduced by the centre-distance, 2-zone design. The negative SA at near largely compensated for the high positive SA introduced by the aspheric lens, removing most myopic defocus when viewing at near. A 0.50 D accommodative lag had little impact on the legibility of typical text (16-point) at the closer viewing distances.Conclusions: All four multi-zone lenses successfully generated myopic defocus at greater viewing distances, but two failed to introduce significant amounts of myopic defocus at the nearest viewing distance due to the combined effects of pupil miosis and negative SA. Typical 16-point type is easily legible at near even in presence of the multi-zone optics of lenses utilised for myopia control and accommodative lag.

We present an interesting case of a child with Marfan's syndrome with ectopia lentis, who was followed for five years. The changes in refractive and visual findings of this child during this period are discussed. The importance of careful oculo-visual examination and possible management options in such children are highlighted.

Background: Retinopathy of prematurity is a vascular retinal disease that can cause blindness in premature new born babies. Several risk factors are associated with the incidence of ROP. Information and data on risk factors associated with ROP in context to Nepalese population is scarcely documented in literature. Objectives: The purpose of this study was to evaluate the risk factors of retinopathy of prematurity in premature infants admitted in the neonatal intensive care unit of Tribhuvan University Teaching Hospital. Methods: Neonates with gestational age of 36 weeks or less and birth weight of 2000 gram or less admitted to neonatal intensive care unit (NICU), during 2013 to 2015 were screened for retinopathy of prematurity. Risk factors and severity of retinopathy of prematurity were evaluated. The initial examination was carried out at 4-6 weeks after birth by indirect ophthalmoscope and retinopathy of prematurity positive and negative infants were compared subsequently. The Chisquare and independent t-tests were used for statistical analysis. A p value less than 0.05 was considered statistically signifi cant. Results: The incidence of retinopathy of prematurity was 22.6% and severe retinopathy of prematurity requiring treatment was observed in 3.2% of 93 neonates who had eye examinations. There was a signifi cant relationship between the occurrence of ROP and birth weight (p=0.000), gestational age (p=0.000), duration of oxygen therapy (p=0.009) and sepsis (p=0.002). However, insignifi cant relationship was observed between the occurrence of retinopathy of prematurity and gender, type of delivery, multiple gestation, premature rupture of foetal membrane, respiratory distress syndrome and hyperbilirubinaemia. Conclusion: The risk factors contributing to development of retinopathy of prematurity showed signifi cant relationship with immaturity, duration of oxygen supplementation and septicaemia.

Myasthenia gravis is a common disorder of the neuromuscular junction characterized clinically by muscle weakness and fatigability. Ocular myasthenia is often misdiagnosed in the initial stages due to the fluctuating nature of ptosis and diplopia. Here, we describe the clinical characteristics of ocular myasthenia gravis along with the diagnostic difficulties in a tertiary eye care center in Nepal. We retrospectively reviewed the charts of the patients diagnosed as ocular myasthenia gravis in Neuro-ophthalmology clinic, BPKLCOS, from 2010 to 2013. The diagnosis of ocular myasthenia was based on the association of typical history and signs together with at least one of these features: unequivocal improvement of ocular signs after injection of neostigmine, positive response to electrophysiological tests and detection of serum antibodies to acetylcholine receptors. There were 24 cases of diagnosed ocular myasthenia gravis during the 3 years. Among them 11 cases (45.8%) were males and 13 cases (54.1%) were females. The mean age was 32.04±19.56 years with the age range from 9 years to68 years. The most common symptoms among patients were drooping of the lids (45.8%, n=11), followed by both double vision and drooping of the lids (37.5%, n=9) and only intermittent double vision in16.6% (n=4). In two patients (9.09%) CT-scan findings were suggestive of thymoma. The symptoms were resolved with anticholinesterases alone in 66.6% (n=16) and anticholinesterases were supplemented with immunosuppressive drugs in 33.3% (n=8) patients. Ocular myasthenia is often misdiagnosed in the initial stages due to its fluctuating nature. With a high index of clinical suspicion simple clinical tests accompanied by pharmacological tests can be useful in diagnosing the condition.DOI: http://dx.doi.org/10.3126/jcmc.v4i3.11931Journal of Chitwan Medical College 2014; 4(3): 5-8