Spectacle Correction Research Articles

A Study To Compare The Accuracy Of Interpupillary Distance Measured Using Interpupillary Distance Ruler With That Of Neidek Autorefractometer

The purpose of this study is to compare the accuracy of interpupillary distance (IPD) measured using an Interpupillary distance (IPD) ruler with that of a needed auto refractometer. The validity of both the test are compared and normal data for each individual were established. To assess the accuracy of Interpupillary distance measured using IPD ruler with that of Neidek auto refractometer. The IPD is a very cardial measurement that had to be calculated for patients with spectacle corrections before selecting frames. A cross-sectional study involving 150 subjects was conducted in the OPD of the Department of Ophthalmology in a Medical college in Chennai. Interpupillary distances had been measured using the IPD ruler and the Neidek auto refractometer, during a period of 3 months.IPD measurements from 150 subjects were obtained using IPD ruler and Neidek auto refractometer. From the study, it was found that there is a no significant difference between the IPD measured using IPD ruler with that of Neidek auto refractometer. IPD measured using IPD ruler is accurate to the IPD measured using Neidek auto refractometer.

Prevalence and determinants of uncorrected refractive error among a socially vulnerable older adult population living in Armenia

ObjectiveThis study estimated the prevalence of uncorrected refractive error (URE) and its determinants in a socially vulnerable older population living in Armenia. Study designThe study design used in the stidy is a cross-sectional study. MethodsA total of 485 people responded to a survey on sociodemographic characteristics, spectacle use, and ophthalmic services’ use. All participants underwent a comprehensive ophthalmic examination including assessment of presenting and best-corrected visual acuity, measuring intraocular pressure and dilated eye fundus examination. Patients who had presenting visual acuity (<6/12) but improved ≥ one line with/without available spectacles after refraction in the better eye were considered to have URE. Descriptive statistics described the sample and estimated the prevalence of the URE in the population. Logistic regression models were used to evaluate its determinants. ResultsThe mean age of participants was 74.5 (7.27) years, ranging from 51 to 94 years. Women constituted the majority of participants (86%). The prevalence of URE in the better eye was 26%. In bivariate analysis, those who were older and who had less than 10 years of education had higher odds of URE than younger and more educated respondents. In multivariable analysis, only education remained associated with URE (OR = 3.71; 95% CI: 1.10–12.5). The rate of normal vision (≥6/12) improved from 58.9% to 81.5%, whereas the rate of visual impairment (<6/12) decreased from 41.1% to 18.5% after best correction in the better eye. ConclusionThe prevalence of URE was high in this study population. The findings warrant the need for eye screening and provision of affordable spectacle correction to the target population in Armenia.

Case Report: Low Vision Management in A 5-Years-Old Due to Retinopathy of Prematurity for Life Quality Improvement

Management of low vision in pediatric patients with greater result can affect their quality of life than in adult low vision patients. Retinopathy of prematurity is the main cause of blindness in children. A case study highlights the tertiary prevention (low vision examination and management) in a 5 year old boy with ROP related blindness to optimize his remaining visual capacity by using optical and non-optical aids that support daily activity and educational learning. A 5-year-old boy with ROP related blindness visited to the low vision clinic after receiving the several treatments for ROP before. His visual acuities were light perception in the right eye and hand movement in the left eye using his current spectacle correction. He had anti VEGF bevacizumab intravitreal injection, vitrectomy and complicated cataract extraction history on the left eye. He was difficult to learn and read numbers and alphabets caused by visual impairment. Upon evaluation by assessment low vision method, his distance visual acuity in the left eye was improved significantly up to 3/40 on LEA Acuity chart with +14.00D. His near vision became 10 M at 30 cm of reading distance (without near correction) and 4 M at 13 cm improved with +3.00 D by spectacle. The non-optical aid devices as reading task were also suggested to improve continuous reading text without difficulty. ROP blindness can be preventable if appropriate, adequate and accessible screening programmes are available. Unfortunately, even with the current screening guidelines and recommended treatment of ROP, many babies suffer from blindness by this disease each year. Low vision assessment and management in pediatric patient with visual impairment according to children need can optimize the recent visual capability of low vision patient and give selfcare daily activity and educational learning.

Effect of spherical rigid gas permeable lens on correction of corneal astigmatism

Background: Objectives were to study an effect of spherical RGP (rigid gas permeable) contact lens in correcting high corneal astigmatism more than 3 diopter.Methods: Total 48 eyes with corneal astigmatism greater than 3.00 diopter were included in study. At the first visit, routine preliminary examination, parameter assessment and subjective refraction has been carried out followed by patient counselling for RGP lens wear. Based on the corneal parameters considering keratometry as well as corneal topography, RGP lens trial was done. Post adaptation period, lens fitting analysis was done by understanding Fluorescein pattern with slit lamp and over refraction was done. Final lens has been ordered on this basis with understanding of tear lens formed, lens performance on cornea and edge width minimal of 0.80 mm to 1.00 mm. Patients were assessed at an interval of every two months from a date of lens dispensing.Results: The spherical RGP lens did correct the corneal astigmatism of more than 3D by formation of tear lens between cornea and lens. Vision improved by 2 to 3 lines compared to the spectacle correction without compromising corneal integrity at the central or peripheral cornea. Keratoconic eye showed significant vision improvement without the use of toric lens.Conclusions: Astigmatic eyes showed significant improvement in acuity with spherical RGP lens without compromising corneal integrity.

Prevalence and causes of visual impairment among hearing impaired students in Lagos, Nigeria

ObjectivesTo determine the prevalence and causes of visual impairment in hearing-impaired students in Lagos, Nigeria and to assess their level of ophthalmic care utilization. MethodsDescriptive cross sectional study carried out in a primary school for hearing impaired students in Lagos, Nigeria. Socio-demographic characteristics, medical and ocular history were obtained. Ocular examination comprised of distance and near visual acuity assessment; cover tests; anterior segment examination and direct fundoscopy. Visually impaired students had cycloplegic refraction, dilated fundoscopy and subjective refraction. In-depth interviews were carried out for parents of students requiring referral for further eye care. ResultsOne hundred and nine students participated in the study. The prevalence of visual impairment was 19%. The causes of visual impairment were refractive error (11%), amblyopia (6%), cataract (1%) and macular scarring (1%). A lower mean age (p = 0.020) and ocular misalignment (p = 0.037) were associated with visual impairment on multivariate analysis. The spectacle correction coverage was 11% and only 8% of the students had prior ophthalmic care utilization. Ignorance of ocular morbidity and perceived inaccessibility of eye care were cited by parents/guardians as reasons for poor utilization of eye-care services. ConclusionA high prevalence of visual impairment was found among the hearing impaired students; uncorrected refractive error and refractive amblyopia were the most prevalent causes. The level of prior ophthalmic service utilization was found to be low. It was recommended that ophthalmic services especially refractive services should be made available in schools for the hearing impaired.

Fundamentals of ophthalmic dispensing part 13: Eye movements

In the second article focusing on binocular vision as an influence upon spectacle correction, Peter Black and Tina Arbon explain the anatomical basis of eye movement and how each eye moves relative to the other (C76782, one distance learning CET point suitable for optometrists and dispensing opticians)

Estimation of final cylindrical spectacle correction by Pentacam

Background and Objectives: Keratoconus is a non-inflammatory asymmetric corneal degenerative disease characterized by the steepening and distortion of the cornea. In this disease, irregular astigmatism makes the subjective refraction difficult. Using the Pentacam, we aimed to determine the corrective astigmatism of the spectacle. Methods: The subjective refraction and Pentacam imaging were performed for 317 keratoconic patients who referred to the Salouti Eye Clinic, Shiraz, Iran. Then, the astigmatism values obtained with subjective refraction were compared with the values of anterior and posterior corneal surface astigmatism obtained with the Pentacam imaging. Results: The mean age of 317 keratoconic patients was 29.81 years (range: 15 to 45 years). The minimum, maximum, and average astigmatism of the corneal front surface were 0.3, 16.8, and 3.21 diopters, respectively. Also, the minimum, maximum, and average astigmatism of the corneal back surface were 0, 2.8, and 0.67 diopters, respectively. Moreover, the P value was lower than 0.001 in the regression analysis of the subjective refraction for both the power and axis of the cylinder. Conclusion: The regression formulas obtained in this study can accurately (with a probability of 99%) predict refractive astigmatism, using corneal astigmatism.

Augmented medial rectus muscle recession versus medial rectus recession with posterior scleral fixation in partially accommodative esotropia: a randomized clinical trial

To compare the postoperative alignment after medial rectus muscle posterior scleral fixation versus augmented recession in children with partially accommodative esotropia (PAET) without convergence excess. In this prospective study, 60 children with PAET without convergence excess were randomly assigned to either augmented medial rectus recession, based on the average of distance angle with correction and near angle without correction, or medial rectus recession, based on distance angle with correction, combined with posterior scleral fixation. The ductions, versions, angles of deviation, and difference between angles were analyzed before and 6months after surgery. Complete success was defined as orthotropia to within 8Δ of esophoria/tropia for both distance and near, with spectacle correction, at 6months. Patients who developed any exophoria/tropia with their original spectacles and needed reduction of their hyperopic correction to achieve successful outcome were defined as qualified successes. Of the 60 children, 25 in the augmented group and 28 in the posterior fixation group completed follow-up. The mean age at surgery was 4.90±2.34years. The complete success rate was 48% and 64% in the augmented and posterior fixation groups, respectively (P=0.15); the qualified success rate was 80% and 92.9%, respectively (P=0.17). Success rate was significantly higher (P=0.04) in the posterior fixation group (56%) than in the augmented group (18%) when the preoperative angle disparity was ≥20Δ. Medial rectus posterior scleral fixation can improve the success rate in PAET with large angle disparity.

The Wearing Rate of Vision Correction Spectacles in Korea(2013~2019)

Purpose : The prevalence of myopia has been increasing worldwide and it was reported that there is a significant increase in prevalence, especially in East Asia. In particular, the proportion of myopia in Korea is quite high, and the rate of wearing the spectacles is expected to increase. This study intends to compare and analyze the wear rate of vision correction glasses by year, and to apply them as basic data for various studies on spectacles wear. Methods : As a research method, 1,500 adult men and women over 19 years of age were involved to survey with a structured web questionnaire using CATI (computer assisted telephone interviewing) of wired and wireless RDD (Random Digit Dialing). Results : In 2019, the adult's wear rate by years was 46.3% for ‘only glasses’, 8.2% for ‘both them’, 0.9% for ‘only contact lens’, and ‘total’ for 55.4%. By gender, ‘only use glasses’ was high with 49.3% for men and 43.3% for women. By generation, ‘both use’ was high with 27.5% in the 20s. In the 30s, 40s, and 50s, ‘only use glasses’, the highest. By occupation, Only students had a high of ‘both use’ and other occupation groups had high of ‘only use glasses’. By income, regardless of income by income, the ratio of ‘only use of glasses’ was the highest. In 2019, the young’s wear rate by years was 33.7% for ‘only use glasses’, 5.3% for both, 1.9% for ‘only use contact lenses’, and 40.9% for ‘total’. By grade, ‘only use glasses’ was high in all grades. Conclusion : It was revealed that the rate of wearing glasses for vision correction compared to the prevalence of myopia decreased in 2019. As optometrist, we should improve public awareness and, through continuous efforts, promote the importance of vision correction glasses and strive for the public's vision life.

VISUAL REHABILITATION AFTER PENETRATING KERATOPLASTY

Introduction: Astigmatism is the most common cause of suboptimal vision after corneal transplantation despite a clear corneal graft.1 Based on several studies, 15–31% of patients undergoing penetrating keratoplasty (PK) may develop postoperative astigmatism greater than 5 diopters (D).2,3 Commonly practiced techniques for visual rehabilitation after PK consist of postoperative suture manipulation, optical correction consisting of spectacles and contact lenses, relaxing incisions, compression sutures, laser refractive surgery, insertion of intrastromal corneal ring segments, wedge resection, toric phakic intraocular lenses, and finally regrafting.4 The aim of this study was to report our management strategies and their results performed for visual rehabilitation and management of astigmatism after PK. Patients and Methods: The records of 104 eyes of 98 patients (54male/44 female) who underwent PK between January 2013 and January 2015 in Baskent University Faculty of Medicine, Department of Ophthalmology were reviewed. The age, the indication for PK, interventions performed for visual rehabilitation, the duration of follow-up, the topographic and refractive astigmatism at the end of follow-up and the final BCVA were recorded. Results: The mean age of the patients was 54±23 years. The indications for PK included keratoconus, Fuch’s endothelial dystrophy, pseudophakic bullous keratopathy and corneal scarring (Figure 1).Fig. 1. The mean duration of follow up was 23±11.5 months. Suture adjustment and selective suture removal were performed 2 to 6 weeks and after 3 months in eyes with more than 3 D of corneal astigmatism. Spectacle correction was performed in 86 eyes (83%) and contact lenses including rigid gas permeable and scleral lenses were fitted in 18 eyes (17%) who were unsatisfied with spectacle correction mostly due to higher order aberrations or high anisometropia (Figure 2).Fig. 2. Relaxing corneal incisions were performed in 23 eyes (22%) and toric intraocular lens implantation was performed in 34 eyes (33%) with cataracts. The mean topographic and absolute refractive astigmatism at the end of follow up was 3.4±2.6 D and 3.6± 1.9 D, respectively. Discussion: Intraoperative and postoperative suture manipulation have been described for minimising early postoperative astigmatism.5,6 After PK, sutures should be kept for at least one year. During this period, astigmatism >4 D can be reduced by suture manipulation consisting of selective interrupted suture removal and tension adjustment of running sutures.4 If significant astigmatism remains after suture removal, which cannot be corrected by optical means such as spectacle correction or contact lenses, surgical procedures can be performed.4 Conclusion: Although general guidelines are useful, it is important to individualize the management based on corneal topography and patient expectations for successful visual rehabilitation.

The impact of hybrid contact lenses on keratoconus progression after accelerated transepithelial corneal cross-linking.

To investigate the effect of hybrid contact lenses (HCLs) on keratoconus (KCN) progression after accelerated transepithelial cross-linking (A-TE CXL). Thirty-five eyes of 26 patients who preferred Ultrahealth HCLs for an optical correction after A-TE CXL formed the study group, and 45 eyes of 34 patients who preferred spectacle correction were age- and sex-matched to form the control group. Corrected distance visual acuity (CDVA), maximum keratometry, mean keratometry, apical posterior keratometry, cylindrical power, minimum corneal thickness, keratoconus vertex indices and curvature asymmetry indices obtained by Scheimpflug corneal topography were compared before, 6 and 12months after the procedure. Anterior segment optic coherence tomography (AS-OCT) was performed to measure the apical corneal clearance of HCL-wearing patients. The median pre-CXL CDVA value of the patients in the HCL group was logMAR 0.30 (0.20-1.0), and it was logMAR 0.30 (0.10-1.0) in the spectacle-corrected group. There was a significant increase in CDVA 6 and 12months after CXL procedure in both groups (p < 0.001, 0.003, respectively). The median front curve asymmetry index (FCAsym) significantly improved after A-TE CXL in the HCL group. The pre-CXL and 12th-month topographic comparisons of the spectacle-corrected group revealed no significant difference. In addition, no significant difference was observed between topographic alterations of two groups (p > 0.05). The CDVA significantly improved, and KCN progression was halted in patients wearing HCL 12months after A-TE CXL. Besides, FCAsym indices can be considered for follow-up of the HCL-wearing patients as an assistive parameter to AS-OCT measurements.

Controlled blood sugar improves the eye’s accommodative ability in type-1 diabetes

To evaluate the impact of blood sugar level on ocular measures, including refractive error (RE), amplitude of accommodation (AoA), and lag of accommodation (LoA), in pre-presbyopes with type-1 diabetes. The fasting blood sugar (FBS) and ocular measures of type-1 diabetes patients (age: 14-39 years; n = 30) on insulin treatment was recorded while they fasted on two separate visits, at baseline and 3 months later. The AoA and LoA was measured with the appropriate spectacle correction worn. The Welch's t-test was used for comparison of the baseline measures between the normal FBS ≤ 7 (n = 10) and higher FBS > 7 (n = 20) patients, and the paired t-test used to investigate for differences between the baseline and follow-up data in patients with changes in FBS. On average, the spectacle correction for the normal FBS group was marginally more myopic (RE: -0.30 ± 0.67 D vs. +0.18 ± 1.00 D, p = 0.032), and they showed greater AoA (5.38 ± 1.08 D vs. 3.68 ± 1.43 D, p < 0.001) and lower LoA (1.00 ± 0.30 D vs. 1.30 ± 0.38 D, p = 0.004) compared with the higher FBS group at baseline. On the follow-up visit attended by 25 patients, the FBS of 15 patients was reduced by an average of 7.0 mmol/L, 8 patients had an average increase of 5.2 mmol/L, while 2 patients recorded no changes relative to the baseline. The patients whose FBS was reduced showed improvement in the mean AoA from 3.78 ± 1.58 D to 4.88 ± 1.61 D (p < 0.001) and a reduction in the mean LoA from 1.37 ± 0.40D to 0.87 ± 0.19D (p < 0.001), whereas those with deteriorated control of the FBS showed an opposite trend. Controlling hyperglycemia improves ocular accommodation in type-1 diabetes.

Prevalence and pattern of amblyopia in a rural hospital in Ghana

ABSTRACT Amblyopia is a developmental ocular disease of childhood-onset which may lead to persistent sequelae into adulthood. Early detection and management of amblyopia usually result in an improved visual outcome. The purpose of this study was to determine the prevalence and pattern of amblyopia in a rural hospital in Ghana. Clinical records of patients seen (from January 2014 to December 2018) at Westphalian Medical Center, Oyoko, Ashanti Region, Ghana, were reviewed retrospectively. Unilateral amblyopia was defined as a two-line interocular difference or more in visual acuity. Bilateral amblyopia was defined as best-corrected visual acuity (BCVA) of Snellen 6/12 or worse in both eyes, with evidence of bilateral ametropia or obstruction of the visual pathway. Following a review of 12,602 patient records, 258 cases of amblyopia were identified. The mean (±SD) presenting age of amblyopic patients was 24.3 ± 16.1 years, with a male-to-female ratio of 1:1.1. The period prevalence of amblyopia was 2.04%. The period prevalence of unilateral and bilateral amblyopia was 1.38% and 0.66%, respectively. The most prevalent form of amblyopia was refractive with a cumulative prevalence of 1.42%. Strabismic and stimulus deprivation amblyopia accounted for 0.36% and 0.21% of all amblyopic cases, respectively. A major cause of amblyopia in this population was refractive error, hence the use of spectacle correction for its initial management. Repeated assessment after an appropriate period of refractive adaptation would elucidate the proportion of amblyopias needing additional treatment modalities. Vision screening for early detection of amblyopia in childhood with accessible and effective management of amblyopia (including refractive correction and occlusion treatment) is necessary to reduce the impact of amblyopia in Ghana.

Keratorefractive Surgery for Residual Refractive Error Correction in Pseudophakic Patients

Purpose. Evaluation of the visual and refractive results of additional correction using LASIK and PRK methods in patients with residual refractive error after previous cataract surgery.Patients and methods.The prospective open study included 57 patients (79 eyes) who previously underwent cataract phacoemulsification (n = 37) or refractive lensectomy (n = 42) with various IOL models implantation (2012–2017). The average age of patients was 50.8 ± 13.9 (19–79) years. Operations LASIK (91.1 %) and PRK (8.9 %) were carried out according to standard methods. In 6 cases, femtosecond laser supported by laser correction. The target refraction ranged from –0.25 to 0.25 D in most (97.5 %) cases. The follow-up period ranged from 6 to 9 months.Results. The patients were divided into groups according to the type of residual refractive error (Group 1 — myopia, group II — emmetropia and group III — hyperopia). Statistically significant differences were determined for the species of previously implanted IOLs — in group II, the frequency of monofocal IOLs was significantly higher (p &lt; 0.05). In group II, the values of the cylindrical component of refraction were significantly higher compared with groups I and III (p &lt; 0.05). In group I, a significant (p &lt; 0.05) decrease in the spherical component of refraction from –1.36 ± 0.92 to –0.2 ± 0.8 D was observed. In patients of group II, there was a slight increase in the spherical component of refraction from 0 ± 0.20 to 0.25 ± 0.29 D (p &gt; 0.05). In group III, a significant (p &lt; 0.05) decrease was observed in the spherical component of refraction from 1.27 ± 0.69 to 0.43 ± 0.49 D. When analyzing the cylindrical component of refraction in group I, its decline was noted from –0.69 ± 0.5 to –0.38 ± 0.46 D (p &gt; 0.05). In group II, the largest decrease in the cylindrical component was observed from –1.6 ± 1.0 to 0.03 ± 1.10 Dptr (p &lt; 0.01). In all the studied groups, a statistically significant (p &lt; 0.05) increase in UCFVA was revealed in the postoperative period. Indicators K1 and K2 did not significantly change.Conclusion. The high efficiency of the correction using the LASIK, PRK and femtoLASIK methods on pseudophakic eyes with the achievement of the target refraction in most of the studied cases was shown. This method can be used as an alternative to spectacle and contact correction in patients with residual refractive error after cataract phacoemulsification and refractive lensectomy with IOL implantation.

Short-time evaluation on intraocular scattering after implantable collamer lens implantation for correcting high myopia

BackgroundTo compare the intraocular scattering before and after implantation of implantable collamer lens (ICL) V4c for correction of high myopia in a short term.MethodsIn this study, 38 eyes of 19 patients who underwent the implantation of ICL V4c were followed up for 3 months. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), objective scattering index (OSI), modulation transfer function cutoff frequency (MTF cutoff), strehl ratio (S/R), OV100%, OV20% and OV9% were measured pre- and postoperatively. Meantime, the Pseudophakic Dysphotopsia Questionnaire (PDQ) was scored to evaluate the subjective satisfaction of intraocular scattering pre- and postoperatively.ResultsThe UCVA were − 0.02 ± 0.06, − 0.03 ± 0.07 and − 0.04 ± 0.07 logMAR at 1 week, 1 month and 3 months postoperatively which were significantly better than those preoperatively (P < 0.05). The BCVA were − 0.09 ± 0.09, − 0.09 ± 0.1 and − 0.1 ± 0.11 logMAR at 1 week, 1 month and 3 months after surgery, which were better than those before surgery significantly (t = 15.64, P < 0.05). The mean OSI were 2.37 ± 1.6, 1.63 ± 0.94, 1.5 ± 0.86 and 1.43 ± 1.05 preoperatively, 1 week, 1 month and 3 months postoperatively which was found significant difference (F = 12.92 P < 0.05). No significant differences were found in MTF cut off (F = 0.61, P = 0.62), S/R (F = 0.58, P = 0.36), OV100% (F = 0.966, P = 0.65), OV20% (F = 0.121, P = 0.96) and OV9% (F = 1.01, P = 0.30) between pre- and postoperatively. The PDQ results indicated that intraocular scattering reduced at 3 months after surgery significantly (P < 0.05).ConclusionsThe ICL V4c implantation for correcting high myopia induced less intraocular scattering and visual disorder than spectacle correction.

Clinical trial to evaluate the therapeutic benefits of limbal-supported contact lens wear for ocular sequelae due to Stevens-Johnson syndrome/toxic epidermal necrolysis

PurposeTo analyze the therapeutic benefits of limbal-supported contact lens (CL) wear in patients with ocular sequelae due to Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN). MethodsThis interventional study enrolled 10 chronic SJS/TEN eyes with a spectacle best-corrected visual acuity (BCVA) of between 0.01 and 0.7 that were fitted with a limbal-supported CL. At baseline and at after 3-months CL use, CL-wear BCVA and the 25-item National Eye Institute Visual Function Questionnaire (NEI VFQ-25) scores were measured, and then compared. Incidence rates and severities of adverse events were also analyzed. ResultsAt after 3-months CL use, BCVA with the fitted CL significantly improved compared to that with spectacle correction at baseline (LogMAR: 0.76−0.15) (P = 0.0039), all NEI VFQ-25 scores improved, however, only in ocular pain and mental health showed statistically significant improvement (P = 0.0078 and 0.0039). No serious adverse events were observed during the follow-up. ConclusionWearing of the limbal-supported CL improved vision compared to spectacles and reduced ocular pain in patients with ocular sequelae due to SJS/TEN.

Effects of spectacles and telescopes on visual function in students with oculocutaneous albinism.

To investigate the effects of spectacle and telescope corrections on visual acuity (VA), contrast sensitivity (CS) and reading rates (RR) in students with oculocutaneous albinism (OCA). An observational study design was conducted on 81 students with OCA. Distance and near VA, CS and RR were measured without correction, with spectacle correction and with a combination of spectacle correction and telescopes. The mean distance and near VA values with a combination of spectacle correction and telescopes were significantly better than those without correction and with spectacle correction alone (p = 0.01). Mean CS values achieved with spectacles alone were significantly better than those obtained with a combination of spectacles and telescopes (p = 0.01). There was no significant difference between logCS values obtained without correction compared to those obtained with a combination of spectacle correction and telescopes. There were no significant differences between RR values obtained with a combination of spectacles and telescopes and those without and with spectacle correction alone (all p > 0.05). This article provides valuable information to eye care practitioners on the effects of spectacles and telescopes on visual acuity, contrast sensitivity and reading rate in students with OCA.

Eye Injuries and Related Risk Factors among Workers in Small-scale Industrial Enterprises

ABSTRACT Purpose We aimed to study eye injuries and their risk factors among workers at small-scale industrial enterprises. Methods Cross-sectional descriptive study. Five hundred workers at small-scale industrial enterprises in Al-Ain City, United Arab Emirates were included. A pre-tested structured questionnaire was used to collect data by direct interviews during the period of October 2018 through June 2019. The outcome measures included self-reported eye injuries, risk factors, and outcomes in the past 12 months. The study adhered to the guidelines of the Declaration of Helsinki. Results One-hundred seventy-five (35%) workers reported eye injury, 25 (14.3%) had recurrent injuries. Twenty-five (15%) received treatment for eye injury. Five percent were hospitalized. Workers who had an eye injury were less educated compared with those who did not (p < .0001), received less safety training (p < .0001), had less work experience (p < .0001), used more spectacle correction glasses (p < .0001), and had less usage of the safety eye goggles and safety eyeglasses (p < .0001) compared with those who had no eye injury. Arc welding (76; 43.4%), chipping (25; 14.3%), and drilling (24; 13.7%) were associated with high risk for eye injury. Twenty-eight percent of eye injuries occurred to observers or working assistants. Conclusions This study has shown a high percentage of eye injury incidents among workers at small-scale industrial enterprises. This was associated with low usage of the safety eye goggles and glasses. Arc welding posed significant risks for eye injury. This information is useful for safety promotion and development of work-related eye injury prevention legislations.

Efficacy of interventions for amblyopia: a systematic review and network meta-analysis

BackgroundMany treatments are currently available for amblyopic patients; although, the comparative efficacy of these therapies is unclear. We conducted a systematic review and network meta-analysis (NMA) to establish the relative efficacy of these treatments for amblyopia.MethodsElectronic databases (MEDLINE, EMBASE, Cochrane Library) were systematically searched from inception to Sep. 2019. Only Randomized clinical trials comparing any two or three of the following treatments were included: refractive correction (spectacles alone), patching of 2 h per day (patch 2H), patch 6H, patch 12H, patch 2H + near activities (N), patch 2H + distant activities (D), atropine (Atr) daily, Atr weekly, Atr weekly + plano lens over the sound eye (Plano), optical penalization and binocular therapy. The reviewers independently extracted the data according to the PRISMA guidelines; assessed study quality by Cochrane risk-of-bias tool for randomized trials. The primary outcome measure was the change in best-corrected visual acuity (BCVA) expressed as log MAR lines. Direct comparisons and a Bayesian meta-analysis were performed to synthesize data.ResultsTwenty-three studies with 3279 patients were included. In the network meta-analysis, optical penalization was the least effective of all the treatments for the change of visual acuity, spectacles (mean difference [MD], 2.9 Log MAR lines; 95% credibility interval [CrI], 1.8–4.0), patch 2H (MD, 3.3; 95% CrI, 2.3–4.3), patch 6H (MD, 3.6; 95% CrI, 2.6–4.6), patch 12H (MD, 3.4; 95% CrI, 2.3–4.5), patch 2H + N (MD, 3.7; 95% CrI, 2.5–5.0), patch 2H + D (MD, 3.5; 95% CrI, 2.1–5.0), Atr daily (MD, 3.2; 95% CrI, 2.2–4.3), Atr weekly (MD, 3.2; 95% CrI, 2.2–4.3), Atr weekly + Plano (MD, 3.7; 95% CrI, 2.7–4.7), binocular therapy (MD, 3.1; 95% CrI, 2.0–4.2). The patch 6H and patch 2H + N were better than spectacles ([MD, 0.73; 95% Crl, 0.10–1.40]; [MD, 0.84; 95% CrI, 0.19–1.50]).ConclusionsThe NMA indicated that the efficacy of the most of the examined treatment modalities for amblyopia were comparable, with no significant difference. Further high quality randomized controlled trials are required to determine their efficacy and acceptability.Systematic review registrationCRD42019119843.

Using Artificial Intelligence and Novel Polynomials to Predict Subjective Refraction

This work aimed to use artificial intelligence to predict subjective refraction from wavefront aberrometry data processed with a novel polynomial decomposition basis. Subjective refraction was converted to power vectors (M, J0, J45). Three gradient boosted trees (XGBoost) algorithms were trained to predict each power vector using data from 3729 eyes. The model was validated by predicting subjective refraction power vectors of 350 other eyes, unknown to the model. The machine learning models were significantly better than the paraxial matching method for producing a spectacle correction, resulting in a mean absolute error of 0.301 ± 0.252 Diopters (D) for the M vector, 0.120 ± 0.094 D for the J0 vector and 0.094 ± 0.084 D for the J45 vector. Our results suggest that subjective refraction can be accurately and precisely predicted from novel polynomial wavefront data using machine learning algorithms. We anticipate that the combination of machine learning and aberrometry based on this novel wavefront decomposition basis will aid the development of refined algorithms which could become a new gold standard to predict refraction objectively.