One-Year Results of a Posterior Chamber Toric Phakic Intraocular Lens Implantation in Patients with Keratoconus.

Purpose: To determine clinical and refractive results after the implantation of EyeCryl Phakic Toric intraocular lens in patients with stable keratoconus. Methods: The study included all patients diagnosed with keratoconus who underwent implantation of an EyeCryl Phakic Toric intraocular lens (Biotech Healthcare Holding; Ahmedabad, India) in at least one eye and had a follow-up of at least 12 months. Visual and refractive data were collected for all patients, along with corneal tomography measurements using Pentacam, and vault measurement using optical coherence tomography. This retrospective study was conducted at a high-volume private refractive surgery center in Medellín, Colombia. Results: A total of 83 eyes from 47 patients were included in the study. The majority (71.1%) were female, with a mean age of 31.2 ± 5.1 years. After 12 months of follow-up post-surgery, the spherical equivalent improved significantly from -8.19 ± 4.04 D to -0.06 ± 0.48 D (p < 0.001). Furthermore, 77% of eyes had a post-surgical spherical equivalent within ±0.50 D, while 92% had residual astigmatism ≤0.50 D. Twelve months after surgery, mean manifest astigmatism was -0.28 ± 0.27 D. Uncorrected visual acuity also showed improvement, from 1.11 ± 0.35 LogMAR to 0.14 ± 0.11 LogMAR. Moreover, 52.4% of eyes demonstrated an improvement of at least one line in best-corrected visual acuity. Notably, no intraoperative or postoperative complications were observed in the study population. Conclusion: The implantation of EyeCryl Phakic Toric intraocular lenses represents a highly effective and safe option for correcting refractive errors in patients with a history of keratoconus. Refractive accuracy is excellent, and a significant proportion of patients experienced an improvement in their best-corrected vision by at least one line.

Refractive errors, amblyopia risk factors and vision screening in children aged 7-10 years in Aotearoa New Zealand.

CLINICAL RELEVANCE: Vision screening is important for detecting undiagnosed vision conditions that are common in school-aged children. However, current vision screening protocols are poor at detecting vision conditions that are most common in the Aotearoa New Zealand paediatric population. BACKGROUND: Uncorrected refractive error and amblyopia are the most common causes of visual impairment in children. The most appropriate vision screening method depends on the refractive error profile of the population. This study aimed to: estimate the prevalence of refractive errors and amblyopia risk factors among children living in Aotearoa New Zealand; describe previous participation in preschool vision screening and determine the diagnostic accuracy of potential screening methods. METHODS: Children aged 7-10 years received comprehensive eye examinations, including cycloplegic refraction, in their school. Eye examination results were assessed for refractive error and amblyopia risk factors. The sensitivity and specificity of individual vision tests for detecting any vision conditions was calculated to assess the most effective tests for vision screening. RESULTS: Eye examinations were completed for 237 children and cycloplegic refraction data was available for 220 of these children. Significant refractive error (need for glasses) was detected in 23.6% of children (7.7% myopia, 7.7% hyperopia, 15.0% astigmatism). Amblyopia risk factors were detected in 9.1% of children. Preschool vision screening had been completed by 78.5% of children. Distance visual acuity screening alone had a sensitivity of 39% for detecting vision conditions, with addition of the Spot Vision Screener improving sensitivity to 65%. CONCLUSION: Astigmatism is the most frequent refractive error among children aged 7-10 years living in Aotearoa New Zealand. Distance visual acuity screening alone is ineffective in detecting refractive error in children in Aotearoa New Zealand. Further research investigating refractive errors across the paediatric population in Aotearoa New Zealand is required to determine the optimal timing and appropriate protocols for school-aged vision screening.

Prevalence of visual abnormalities detected through paediatric vision screening in Queensland, Australia.

BACKGROUND: Vision screening programs can provide epidemiological information regarding visual impairment in children. This study aims to report the characteristics of visual abnormalities diagnosed through the Primary School Nurse Health Readiness Program (PSNHRP) in Queensland, Australia. METHODS: A retrospective review of vision screening records from the PSNHRP between January 2017 and December 2020 was undertaken. Children aged between 4 and 7 who underwent vision screening were included for review. Children with a visual acuity of worse than 6/9-1 using the Parr 4 m letter-matching chart or those who failed the SPOT Vision Screener were referred to an optometrist or ophthalmologist for review. RESULTS: 164 890 children underwent vision screening. 12148 children failed visual screening (7.4%) and were referred for an eye assessment. 6011 (69.4%) of the 8659 children who attended ophthalmic review had a confirmed visual abnormality. Of 164 890 screened children, 1187 (0.72%) were confirmed to have anisometropia, 3843 (2.33%) had refractive error, 194 (0.12%) had strabismus, 755 (0.46%) had anisometropic amblyopia, 136 (0.08%) had strabismic amblyopia, and 1356 (0.82%) had an unspecific abnormality. There was no statistically significant difference in the age at screening between any visual abnormality (p = 0.94). Anisometropia, refractive error, and strabismus were significantly more common in females than males (p = 0.03, p < 0.01, and p = 0.03 respectively), whereas anisometropic amblyopia was more common in males (p < 0.01). CONCLUSIONS: We report the prevalence of visual abnormalities detected through the PSNHRP vision screening program. Identification of medical or socioeconomic risk factors that are likely to be associated with visual abnormalities can help to optimise vision screening programs.

Comparison of the PlusoptiX A16 and vision screener V100.

Clinical relevance: This study compares a novel photoscreening device with a previously validated one in a school-age population. It highlights a tendency of the new device to underestimate myopic spherical equivalent and overestimate hyperopic cases. Purpose: To compare the PlusoptiX A16 and Vision Screener V100 photoscreeners in a study population of school-age children. Methods: One hundred and thirty-three children, with a mean age of 6.4 ± 0.5 years, were evaluated using both the PlusoptiX A16 and Vision Screener V100 photoscreeners. The measurements were taken in random order in a room with diminished ambient lighting. Results: The mean refractive error values for the M component were 0.27 ± 0.67D (PlusoptiX A16) and 0.21 ± 0.58D (Vision Screener V100). For the J0 component, means were 0.16 ± 0.38D (PlusoptiX A16) and 0.06 ± 0.33D (Vision Screener V100) and for theJ45 component the means were 0.03 ± 0.17D (PlusoptiX A16) and 0.06 ± 0.22D (Vision Screener V100). When compared both instruments, statistically significant differences were observed for the M (p=0.017) and J0 (p=0.004) components. The agreement rates between PlusoptiX A16 and Vision Screener V100 across different refractive components were 80.5% for sphere, 82.0% for cylinder, and 40.6% for axis when considering a range of ±0.75 D for sphere and cylinder and ±25.0 degrees for cylinder axis. Simultaneously considering all three conditions, the overall agreement was 73.7%. Conclusion: The Vision Screener V100, while generally aligning well with PlusoptiX A16, tends to underestimate myopic spherical equivalent, overestimate hyperopic cases, and underestimate J0 astigmatism.

Study of Visual Evoked Potentials in Schoolchildren: A Promising Aid to Pediatric Ophthalmology.

Background Visual evoked potential (VEP) is a noninvasive investigation conducted to identify abnormalities in the visual system. It is especially suitable for young children who are unable to express visual symptoms or participate in conventional vision tests. This study was undertaken to examine the VEP among schoolchildren to assess the functionality of their optic pathway. Methodology This short-term observational study was performed in the Clinical Neurophysiology Unit of the Physiology Department of a rural medical college. The study population consisted of 60 schoolchildren aged 7-12. Both eyes were examined for transient pattern reversal VEP recordings using a Recorders & Medicare Systems Electromyography-Evoked Potential recorder (RMS EMG-EP MARK-II Pvt. Ltd., Chandigarh, India). Results VEPs were analyzed for latency and amplitude of the main components, namely P100, N70, and N155. The results showed markedly extended P100 latency in 33.33%, i.e., eight out of 24 eyes of standard (std.) III children. Similar latency prolongation was obtained in 36.36% (eight out of 22) eyes of std. IV, 30% (six of 20 eyes) of std. V, 13.63% (three of 22 eyes) of std. VI, and 50% (eight of 16 eyes) in std. VII and VIII children. A markedly reduced P100 amplitude was observed in two of 20 eyes (10%) of std. V, two of 16 eyes (12.5%) in std. VII and VIII children, amounting to a P100 amplitude abnormality in 5% eyes in toto. The interocular differences in all VEP parameters among the subjects were statistically insignificant. Conclusion In schoolchildren in whom normal latencies and amplitudes were obtained, the presence of reproducible VEPs indicated the normal functional status of their visual pathway. On the other hand, in those children where altered VEP findings were found, it hinted toward complementary information that they may have underlying ocular disorders that were yet to be diagnosed. Hence, this study provides insight into the assessment of visual system function, which is primarily difficult in young children.

Ocular manifestations of craniosynostosis in Saudi Arabia.

PURPOSE: Visual and motility disorders have been reported in cases of syndromic and non-syndromic craniosynostosis. However, to the best of our knowledge, no regional or local studies have addressed the prevalence of ocular manifestations in craniosynostosis among Middle Eastern populations. The purpose of this study was to describe the frequency and nature of ophthalmic abnormalities in Arab children with craniosynostosis and to evaluate these findings pre- and post-craniofacial surgery. MATERIALS AND METHODS: A prospective cohort study of 31 children with craniosynostosis. Demographic information was gathered along with genetic results and ophthalmic evaluations, including cycloplegic refraction. RESULTS: Age at presentation to the ophthalmology service ranged from 14 months to 8 years, with a median of 3 years. Sixteen patients were female (52%), and 24 patients had undergone a cycloplegic refraction. Of these, 20.8% had significant refractive errors; of those with refractive errors, 40% were myopic and 60% were hyperopic. Eight patients (25.8%) had papilledema, with significant improvement after craniofacial surgery. Five patients (16%) had visual acuity≤20/30 in at least one eye at baseline with improvements in follow-up visits. CONCLUSION: Craniosynostosis has a significant impact on visual function in the Arab population. Potentially correctable cases of visual impairment, such as those caused by amblyogenic refractive error and papilledema, are commonly encountered; therefore, timely referral and regular ophthalmic evaluation are recommended for these patients.

Refractive Error in Inherited Retinal Disease.

PURPOSE: Inherited retinal dystrophies (IRDs) lead to significant vision impairment. Refractive errors (RE) are also associated with vision impairment and an increased risk of ocular comorbidities and may compound impairment caused by IRDs. Identifying the pattern of RE in IRDs may assist in the better management of patients with IRD and provide insights into understanding genetic associations with RE. The aim of this study was to investigate the patterns of RE in patients with IRD from three academic ophthalmology referral centers. DESIGN: Retrospective tri-center cohort study. METHODS: Chart review of clinically and molecularly confirmed IRD cases seen at the University of California San Diego, Oregon Health & Science University, and Children's Hospital Los Angeles. Data retrieved included: demographics, disease phenotype, genotype, best-corrected visual acuity, objective, and/or subjective refraction. RESULTS: A total of 1942 patient notes were reviewed, of these 634 patients (1255 eyes) had refractive data. For genes associated with myopia, NYX (n=14 [1%]) was associated with the highest SER of myopia (mean -9.26 diopters (D) [95% CI -11.867, -6.651], P<0.001) followed by IMPG2 (n=16 [1.1%]) (mean -4.062 D [95% CI -6.254, -1.871], P=0.002), then RPGR (n=104 [7.2%]) (mean -2.664 D [95% CI [-3.618, -1.710], P=0.016) and for genes associated with hyperopia, BEST1 (n= 38 [2.6%]) had the highest SER for hyperopia (mean 2.996 D [95% CI 1.830, 4.162], P<0.001) followed by RS1 (n=26 [1.8%]) (mean 2.562 D [95% CI 1.454, 3.671], P<0.001), then CNGA3 (n=28 [1.9%]) (mean 0.603 D [(95% CI -0.48, 1.686]), P=0.009). Overall patients with IRD were significantly more myopic than age matched population controls. (n=eyes) CONCLUSION: By combining genetic testing with refraction data from a large cohort of patients, we identify IRD genes associated with myopia and hyperopia. However, we find that the pattern of ametropia varies widely not only by gene but also within a gene cohort. The genes identified to be associated with RE are candidates for further in-depth investigation to understand their functional role in RE.

Late Bedtime and Altered Diurnal Axial Length Rhythms of the Eye.

PURPOSE: Affecting one-third of the population worldwide and increasing, the sight-threatening condition myopia is causing a significant socio-economic burden. To better understand its etiology, recent studies investigated the role of ocular and systemic rhythms, yet results are conflicting. Here we profiled 24-h variations of axial length of the eye and salivary melatonin concentration in young adults with and without myopia and explored the potential impacts of bedtime on these rhythms. METHODS: A total of 25 healthy young adults (age 25.0 ± 4.8 years, 13 females) completed this study, including 13 myopes (mean spherical equivalent refractive error -2.93 ± 1.46 diopters) and 12 non-myopes (0.14 ± 0.42 diopters). Saliva sample collection and axial length measurements were repeated for seven times over 24 h starting from 8 am. Information on sleep and chronotype was collected at first visit with the Pittsburgh Sleep Quality Index and the Morningness-Eveningness Questionnaire. RESULTS: Significant diurnal rhythms of axial length and salivary melatonin concentration were identified in both refractive groups (both p < 0.001), with no myopia-related rhythm difference (interaction of measurement time-point × myopia, p = 0.9). Late bedtime was associated with altered rhythms (p = 0.009) and smaller diurnal change (p = 0.01) in axial length. Elevated melatonin levels were observed in myopes (p = 0.006) and in late sleepers (p = 0.017). CONCLUSIONS: These findings suggest that sleep/wake cycles may be involved in the regulation of axial length rhythms. Further research is needed to determine if there exists a causal relationship between the two.

Prevalence of Amblyogenic Risk Factors Among School Children in India Using the Spot Vision Screener.

INTRODUCTION: Amblyopia is a common cause of preventable visual impairment in children, affecting 1% to 6% globally. This study assesses amblyopia prevalence and risk factors among school children in rural Telangana, India, using the Spot Vision Screener (Welch Allyn, Inc., Skaneateles Falls, New York, USA), a portable, noninvasive device recommended for automated vision screening. METHODS: A cross-sectional study was conducted on 714 schoolchildren aged 5-10 years. Screening was performed using the Spot Vision Screener, evaluating refractive errors, ocular alignment, and other amblyopia risk factors. Children identified with potential amblyogenic factors were referred for comprehensive ophthalmological evaluation to confirm diagnosis. RESULTS: Out of 714 children screened, 84 were referred by the Spot Vision Screener for further evaluation. Subsequent examination by ophthalmologists confirmed amblyopia in 65 children, resulting in a prevalence of 9.10%. Myopic refractive error was the most prevalent (69.23%), followed by astigmatism (21.53%) and hypermetropia (9.23%) among amblyopia cases. CONCLUSION: The Spot Vision Screener proved to be a reliable tool for identifying amblyopia risk factors in school children, facilitating early detection and referral for appropriate management. This study underscores the importance of implementing effective vision screening programs in rural settings to mitigate preventable childhood blindness.

Prevalence and risk factors for refractive error in older adults in eight ethnicities in China: The China national health survey.

Purpose: This study aimed to investigate the prevalence of refractive error (RE) and risk factors for myopia among older adults in the Han and various minority ethnic groups across seven provinces in China. Methods: This cross-sectional study forms a part of the ophthalmic dataset of the China National Health Survey (CNHS). Face-to-face interviews and ophthalmic examinations were conducted in seven provinces located in western and northern China. The age- and sex-adjusted prevalence of RE among Han and seven other ethnic groups aged 50-80 years were compared. A mixed-effects model was used to identify the risk factors associated with RE. Results: A total of 12,902 participants, including 8800 Han and 4102 from ethnic minorities, were included in the study. The age- and sex-adjusted prevalence of myopia, high myopia, hyperopia, and astigmatism ranged from 15.3 % (Manchu) to 22.9 % (Han), 0.2 % (Yugur) to 2.8 % (Han), 21.6 % (Tibetan) to 48.9 % (Uyghur), and 38.7 % (Yi) to 57.5 % (Manchu) across different ethnicities, respectively. Compared to the Han population, the Mongolian (odds ratios (OR) 0.62, 95 % confidence interval (CI) 0.46-0.84, p = 0.002), Tibetan (OR 0.66, 95 % CI 0.52-0.85, p = 0.001), Uyghur (OR 0.63, 95 % CI 0.49-0.80, p < 0.001), Yi (OR 0.65, 95 % CI 0.46-0.92, p = 0.014), and Yugur (OR 0.65, 95 % CI 0.50-0.85, p = 0.001) ethnicities were less likely to have myopia. There was no significant difference in the prevalence of myopia between the Manchu, Korean, and Han ethnic groups. Factors associated with a lower prevalence of myopia included rural residence (p < 0.001), a body mass index (BMI) > 18.5 kg/m2 (all p < 0.001), residence in higher latitude areas (p = 0.020), and a history of smoking (p = 0.002 in the past smoking group, p = 0.031 in the current smoking group). The Mongolian (p = 0.006) and Yugur (p = 0.007) populations, participants living in rural areas (p = 0.012), and those with a BMI >24 kg/m2 (p = 0.038 in the >24.0 ≤ 27.0 kg/m2 group or p = 0.041 in the >27.0 kg/m2 group) were less likely to have high myopia. Factors associated with a higher prevalence of hyperopia included older age (all p < 0.001), rural residence (p = 0.039), higher latitude areas (p = 0.031), smoking history (p = 0.040), and Mongolian (p = 0.001), Uyghur (p < 0.001), Yi (p < 0.001), and Yugur (p = 0.002) ethnicities. Conversely, the Manchu population (p = 0.004) and individuals with higher education levels than illiteracy (p = 0.024 or p < 0.001) were less likely to have hyperopia. Conclusions: Myopia affected more than one-fifth of the older adults in the Han population in this survey. Significant differences in the prevalence of RE were observed between minority ethnicities and Han individuals, except for the Manchu and Korean groups.

Association Between Eyelid Twitching and Digital Screen Time, Uncorrected Refractive Error, Intraocular Pressure, and Blood Electrolyte Imbalances.

INTRODUCTION:  Previous studies have shown that isolated eyelid myokymia (EM) is usually caused by stress, fatigue, and caffeine consumption. The purpose of this study was to evaluate the association between EM and digital screen time, uncorrected refractive error, intraocular pressure (IOP), and blood electrolyte levels. METHODS: Between February 2023 and June 2024, 103 eyes of 103 patients who applied to the ophthalmology outpatient clinic with complaints of eyelid twitching lasting for more than two weeks and 103 eyes of 103 healthy individuals as a control group were included in the study. All participants were asked to record their daily time spent with digital screens for two weeks. Cycloplegic refractive error, IOP, optic nerve head cup/disc (C/D) ratio, and blood calcium, sodium, potassium, and magnesium levels were recorded and compared between the two groups. RESULTS: Mean digital screen time was 4.84±1.74 hours in the control group and 6.88±2.01 hours in the EM group. It was found that digital screen time was significantly higher in the EM group compared to the control group (p<0.001). There was a strong positive correlation between the duration of eyelid twitching and the time spent in front of digital screens (p<0.001, r=0.670). There was no significant difference in cycloplegic refractive error, IOP, C/D ratio, and blood electrolyte levels between the two groups (p>0.05). CONCLUSION: Prolonged digital screen time might play a role in the development of EM. On the other hand, no relationship was found between eyelid twitching and uncorrected refractive error, glaucoma, or blood electrolyte levels.

Objective Refraction Status before and after Cycloplegia: From Childhood to Young Adulthood.

This study aimed to evaluate the clinical information revealed after cycloplegia and assess how age and non-cycloplegic refractive status influence the classification of types of refractive error, as well as the relationship between age and cycloplegia-induced changes in the power of refractive errors. We analysed the records of 472 non-population-based ophthalmology practice patients aged 3-28 years (mean ± SD: 9.1 ± 4.6). Cycloplegia was induced with one drop of cyclopentolate 1% in each eye, and eye refraction was measured 30 ± 5 min later using an objective autorefractometer. Cycloplegia induced a clinically significant (≥0.50 D) hyperopic shift in the spherical equivalent of 60.2% of participants and a myopic shift in 1%, resulting in a 34.1% increase in the frequency of participants with hyperopia, while the frequency of those with myopia and emmetropia decreased by 5.5% and 23.3%, respectively. The average spherical equivalent difference (mean ± SD) induced by cycloplegia was 0.72 ± 0.73 D, with the highest difference observed in the 3-5 years age group (1.18 ± 0.85 D). The differences in astigmatism power (p = 0.84) and astigmatism axis (p = 0.97) between non-cycloplegic and cycloplegic conditions were not statistically significant.

Analysis of the peripheral refraction in myopic adults using a novel multispectral refraction topography.

Purpose: To determine the distribution and characteristics of peripheral refraction in adults with myopia using the novel multispectral refraction topography. Method: A total of 187 adults with myopia were recruited for this study. This study was conducted in two stages. Part I: participants were divided into 6 groups based on the central refraction of the right eyes, Part II: according to the interocular differences in refractive error (IOD) of the central refraction, we divided the participants into isomyopia group (IOD<1.00 D) and anisomyopia group (IOD≥1.0 D). We surveyed the characteristics of peripheral refraction and relative peripheral refraction (RPR), as well as the correlation between RPR and central refraction, age, sex, and axial length. Result: Part I: With an increase in the degree of myopia, relative peripheral hyperopia developed from the center to the periphery. A statistically significant hyperopia shift compared to the center (P < 0.05) was first observed on the temporal side within a 40° field of view at the posterior pole of the retina. The RPR of the temporal, superior, and inferior retinas positively correlated only with age. Part II: In the isomyopic participants, there was no difference in peripheral refraction between the eyes (P < 0.05). In the anisomyopic participants, the RPR of the more myopic eyes was more hyperopic than that of the less myopic eyes in NRDV40-50, SRDV10-20, SRDV30-50, TRDV20-30, TRDV40-50, and IRDV10-40. Conclusion: With an increase in the degree of myopia, relative peripheral hyperopia developed from the center to the periphery, and peripheral refraction progressed at different rates in various retinal zones.

Prevalence and Pattern of Ocular Diseases Among Children Aged 7-14 Years Visiting a Tertiary Care Teaching Hospital in Central India.

PURPOSE:  Ocular morbidity in children hinders their overall development. The prevalence and pattern vary amongst countries as well as within a country. Many ocular diseases if diagnosed and treated on time can prevent ocular morbidity in children to a large extent. The aim of this study is to determine the prevalence and pattern of ocular diseases in children (7-14 years) presenting to the All India Institute of Medical Sciences, Bhopal, a tertiary care teaching hospital in central India. METHODS:  This is a single-center, hospital-based cross-sectional study conducted from June 2018 to August 2019. A total of 1276 children between 7 and 14 years of age were included. A thorough ocular examination was done and a diagnosis was noted. Statistical analysis was performed using Microsoft Excel, Version 2013 (Microsoft Corp., Redmond, WA) and IBM SPSS Statistics for Windows, Version 23 (IBM Corp., Armonk, NY). A p-value of <0.05 was considered significant.  Results: Out of 1276 children, 505 (39.6%) were of 7-10 years while 771 (60.4%) were of 11-14 years. There were 563 females (44.1%) and 713 males (55.9%). The most common ocular morbidity was a refractive error, (653; 51.1%), it was significantly higher in the age group 11 to 14 years than in children of 7 to 10 years of age (p<0.03). The second most prevalent ocular morbidity was infection/inflammation of the adnexa (18.8%) of which males were affected more than females (p<0.0005). The other morbidities were squint and neuro-ophthalmological-related diseases (8.3%), followed by trauma (3%), congenital diseases (2.6%), amblyopia (2.4%), degenerative diseases (0.7%), neoplastic (< 0.01%), and miscellaneous disorders (1.6%). CONCLUSION: The majority of ocular disorders are preventable and treatable. The most common ocular morbidity in our study is refractive error. We recommend school-based screening programs for timely detection and correction of refractive error and to prevent amblyopia.

Telemedicine integration into the eye health ecosystem in scaling of effective refractive error coverage in Kenya.

This study explored the potential of telemedicine integration into the eye health ecosystem with an aim of scaling effective refractive error coverage in Kenya. This exploratory study was conducted telephonically and through online interviews with key opinion leaders, ophthalmologists, optometrists, ophthalmic clinical officers, optical technicians and beneficiaries of the optical technician's services in rural areas. A telemedicine workflow was developed and validated based on the comments from the key opinion leaders using the Delphi technique. Quantitative and qualitative data were analysed using SPSS and NVivo Software respectively. All of the key opinion leaders agreed that telemedicine is relevant in the eye health ecosystem and recognition of primary vision technicians is critical for effective telemedicine integration. The reasons for the need of telemedicine integration were categorized into; good relationship, organized refractive error service delivery, convenience and availability and cost reduction. The possible factors influencing integration of telemedicine identified were categorized into cost, unwillingness, dominance, perception, lack of technical team, policies and network coverage. The limited human resources in the eye health ecosystem in developing countries cannot effectively deliver refractive error services to the growing population. Hence, integration of telemedicine and establishment of policies recognizing telemedicine are desirable to strengthen task shifting and scale effective refractive error coverage.

Accuracy of intraocular lens power calculation formulae for the Yamane technique of secondary fixation: a systematic review and meta-analysis.

OBJECTIVE: This systematic review and meta-analysis aims to assess the refractive outcomes of the Yamane technique for intrascleral fixation of intraocular lenses (SF-IOL) and compare the predictive ability of the various intraocular lens power calculation formulae commonly used in conjunction with the technique. METHODS: A literature search was conducted in the Medline, Scopus, and Cochrane Library databases for articles published from January 2014 to May 2023. Studies that met the predetermined inclusion criteria were included and subjected to analysis. The primary outcome evaluated was the refractive predictive error, defined as the difference between predicted refraction and post-operative manifest refraction. RESULTS: Eleven studies met the inclusion criteria, with a cumulative sample size of 615 patients (mean age: 66.6 years). Various IOL formulae were used, with SRK/T being the most frequently adopted formula. The overall mean refractive predictive error for all formulae combined was -0.02 D, which was not statistically significant (p = 0.99). Subgroup analysis for individual formulae also showed no significant difference from predicted error for any formula (p > 0.05). CONCLUSION: The Yamane technique for SF-IOL shows promising refractive outcomes, and the choice of IOL power calculation formula should be tailored based on patient characteristics and surgeon preference. No formula demonstrated superior predictive ability over others. Further research is needed to develop formulae specifically for eyes with secondary aphakia and poor capsular support.

Sources of reduced visual acuity and spectacle treatment options for individuals with Down syndrome: Review of current literature.

Individuals with Down syndrome are known to have a greater prevalence of ocular conditions such as strabismus, nystagmus, elevated refractive error, poor accommodative function, elevated higher-order optical aberrations and corneal abnormalities. Related to these conditions, individuals with Down syndrome commonly have reduced best-corrected visual acuity at both far and near viewing distances across their lifespan. This review summarises the various optical sources of visual acuity reduction in this population and describes clinical trials that have evaluated alternative spectacle prescribing strategies to minimise these optical deficits. Although refractive corrections may still have limitations in their ability to normalise visual acuity for individuals with Down syndrome, the current literature provides evidence for eye care practitioners to consider in their prescribing practices for this population to maximise visual acuity. These considerations include accounting for the presence of elevated higher-order aberrations when determining refractive corrections and considering bifocal lens prescriptions, even for young children with Down syndrome.

Characteristics of astigmatism in school-age children aged 5 to 13 years in northeast Sichuan: a cross-sectional school-based study.

Background: Astigmatism is closely associated with myopia progression, vision loss, eye fatigue and amblyopia, which seriously endangers children's eye health. This study aims to investigate the prevalence and characteristic distribution of astigmatism in children in Langzhong City, providing valuable insights for allocating resources and develop prevention and control strategies. Methods: A cross-sectional study and random sampling survey were conducted. Between January and November 2021, 21,415 students aged 5 to 13 years from 14 primary schools in Langzhong City underwent non-cycloplegic refractive testing using autorefraction. The data on myopia were analyzed using SPSS (Statistical Package for the Social Sciences) version 23.0. Results: The inclusion criterion was set at an absolute astigmatism value of ≥0.50D. Among the 21,415 children studied, 61.70% were found to have astigmatism. The prevalence of astigmatism varied significantly across different grades (χ2=501.414, P<0.001). The predominant types of astigmatism were mild astigmatism (0.50-1.00D) and with-the-rule astigmatism. Mixed astigmatism was primarily observed in children in grades 1 and 2, while compound myopic astigmatism was more common in children in grades 3 to 6. These differences were statistically significant. As the degree of astigmatism increased, the proportions of against-the-rule astigmatism, oblique astigmatism, compound myopic astigmatism, and simple hyperopic astigmatism decreased, whereas the proportions of with-the-rule astigmatism, mixed astigmatism, and compound hyperopic astigmatism increased. Conclusions: The prevalence of astigmatism among school-age children aged 5 to 13 years in northeast Sichuan is notably high, with compound myopic astigmatism and with-the-rule astigmatism being the most common types. Regular refractive examinations are crucial for the early detection and management of astigmatism.

Myopia dominance in preterm infants without and with retinopathy of prematurity: Indian Twin Cities ROP study (ITCROPS) report number 15.

PURPOSE: To investigate the refractive error profile and progression in infants with different stages of ROP, without ROP, and those who received laser treatment for ROP. METHODS: This retrospective study included the data from 838 infants (baseline mean age 3.7 ± 5.4 months) who had premature birth. Among these, 433 infants had one of the stages of ROP and 405 had no ROP. Infants with ROP were sub-divided into stage 1 (n = 76), stage 2 (n = 142), and stage 3 (n = 136) and aggressive posterior ROP, (APROP, n = 79). They were further categorized into those who received treatment (n = 213) and with no treatment for ROP (n = 220). Data from a subset of 117 infants was used to assess the 1-year change in the refractive error. Myopia was defined as spherical equivalent refraction (SER) <-0.50 diopters (D). Eyes with retinal detachment were excluded. RESULTS: Higher percentage of myopia was found in infants with ROP (39.7%) than no-ROP (19.8%), and it increased with severity of ROP: stage 1: 19.7%, stage 2: 33.8%, stage 3: 45.6%, and 59.5% in APROP. Percentage of myopia doubled in those who underwent treatment for ROP (54.5%) compared to no-treatment group (25.5%). Mean (± SEM) change in SER after 1 year was significantly greater in infants with APROP -4.55 ± 1.38 D and stage 3 ROP -2.28 ± 0.57 D compared to other stages and no-ROP. CONCLUSION: Myopia was found to be more prevalent in preterm infants in general, and more in the presence of ROP. Preterm infants without or with any form of ROP, particularly those with severe form of ROP and those who received treatment require meticulous periodic refractive error assessment.