Spherical Refractive Error Research Articles

Refractive development II: Modelling normal and myopic eye growth.

During refractive development, eye growth is controlled by a combination of genetically pre-programmed processes and retinal feedback to minimise the refractive error. This work presents a basic differential model of how this process may take place. The description starts from two bi-exponential descriptions of the axial power Pax (or dioptric distance) and total refractive power Peye, the difference between which corresponds with the spherical refractive error S. This description is rewritten as an ordinary differential equation and supplemented by a retinal feedback function that combines retinal blur (closed loop) with a term describing excessive axial growth (open loop). This model is controlled by a total of 18 parameters that allow for a wide variety of developmental behaviours. The proposed model reproduces refractive development growth curves found in the literature for both healthy and myopic eyes. An early onset of myopisation, a large growth term and a high minimum for the crystalline lens power all lead to higher degrees of myopia. Assigning more importance to the feedback than to the pre-programmed growth makes the model more sensitive to myopogenic influences. Applying refractive corrections to the model, undercorrection is found to produce more myopia. The model compensates for a low-powered imposed lens and can return to (near) emmetropia if that imposed lens is removed quickly thereafter. Finally, simulating the effect of a diffuser leads to high myopia. Using a series of basic assumptions, the proposed model recreates many well-known experimental and clinical results about refractive development from the literature while placing them in a standardised context. This contributes to a broader understanding of the origins of refractive errors, and future versions may help in the development of solutions for myopia control.

Myopia control with orthokeratology lenses. A 3-year follow-up study including a cross-over design: Clinical study Of Near-sightedness; TReatment with Orthokeratology Lenses 2 (CONTROL2 study).

The purpose of this study is to investigate 3-year efficacy of orthokeratology lenses (OKL) in controlling axial length progression in myopic Scandinavian children. Through a cross-over design of the control group to compare the treatment efficacy in younger versus older children, with the latter having higher cycloplegic spherical refractive error (cSEQ) at treatment initiation. Further, the study aimed to evaluate the safety of the treatment. This was a continuation of the randomized controlled study Clinical study Of Near-sightedness; TReatment with Orthokeratology Lenses (CONTROL study) in which the follow-up period of the original intervention group, that received OKL, was extended from 18 months to 36 months. Meanwhile, the original control group was crossed-over to OKL after the 18-month follow-up visit and treated for 18 months. Biometry was measured using Lenstar LS900, and contact lens complications were graded according to Efron Grading Scale for Contact Lens Complications (Efron score). Mixed models were used for statistical analysis. Nineteen subjects in the OKL group and 28 in the control group completed the CONTROL study. Hereof, 17 and 24 subjects from the OKL group and control group, respectively, agreed to participate in the CONTROL2 study. In the OKL continue group, the treatment efficacy did not decline during the 3-year study period (p-values for follow-up visits were all ≥0.82). There was no statistically significant difference between treatment efficacy when OKL treatment was initiated in younger versus older children (p-value ≥0.14 for all follow-up visits). Low-grade corneal staining was seen in several subjects at some point during the study, but here were no treatment-requiring or sight-threatening adverse events during the study period. The efficacy of myopia control by OKL was stable during 3 years of treatment. Similar treatment efficacies were found regardless of the age at treatment initiation. No severe adverse events occurred during the study period.

Lifelong Changes in the Choroidal Thickness, Refractive Status, and Ocular Dimensions in C57BL/6J Mouse.

To investigate the changes in choroidal thickness (ChT), refractive status, and ocular dimensions in the mouse eye in vivo using updated techniques and instrumentation. High-resolution swept-source optical coherence tomography (SS-OCT), eccentric infrared photoretinoscopy, and custom real-time optical coherence tomography were used to analyze choroidal changes, refractive changes and ocular growth in C57BL/6J mice from postnatal day (P) 21 to month 22. The ChT gradually increased with age, with the thickest region in the para-optic nerve head and thinning outward, and the temporal ChT was globally thicker than the nasal ChT. Retinal thickness remained stable until 4months and subsequently decreased. The average spherical equivalent refraction error was -4.81 ± 2.71 diopters (D) at P21, which developed into emmetropia by P32, reached a hyperopic peak (+5.75±1.38D) at P82 and returned to +0.66 ± 1.86 D at 22months. Central corneal thickness, anterior chamber depth, lens thickness, and axial length (AL) increased continuously before 4months, but subsequently exhibited subtle changes. Vitreous chamber depth decreased with lens growth. ChT was correlated significantly with the ocular parameters (except for retinal thickness) before the age of 4months, but these correlations diminished after 4months. Furthermore, for mice younger than 4months, the difference in the ChT, especially temporal ChT, between the two eyes contributed most to that of axial length and spherical equivalent refraction error. Four months could be a watershed age in the growth of mouse eyes. Large-span temporal recordings of refraction, ocular dimensions, and choroidal changes provided references for the study of the physiological and pathological mechanisms responsible for myopia.

Intraocular lens tilt and decentration after primary and delayed implantation in phacovitrectomy for macula-off rhegmatogenous retinal detachment repair.

To evaluate the tilt and decentration of intraocular lenses (IOLs) in eyes that underwent phacovitrectomy for macula-off rhegmatogenous retinal detachment (RRD) repair. In this retrospective cohort study, 63 patients with macula-off RRD who underwent phacovitrectomy were enrolled and divided into a primary implantation group (group A) and a delayed implantation group (group B) according to the time of IOL implantation. Routine ocular examinations, including optometry, were performed, and the IOL tilt and decentration were measured. Postoperative refractive prediction error and IOL tilt and decentration were compared between the two groups, and the relevant factors of IOL positions were analyzed. The mean spherical refractive prediction error (MSE) was - 0.53 ± 0.39 D in group A and - 0.09 ± 0.55 in group B. The mean absolute spherical refractive prediction error (MASE) was 0.61 ± 0.23 D in group A and 0.50 ± 0.22 D in group B. The difference in MSE (t = -3.623, P < 0.05) but not in MASE (t = 1.866, P = 0.067) between the two groups was significant. The mean IOL tilt and mean decentration were 8.54° ±3.65° and 0.55 ± 0.18 mm in group A and 10.62° ±3.29° and 0.66 ± 0.14 mm, respectively, in Group B. Differences in tilt (t = -2.373, P < 0.05) and decentration (t = -2.698, P < 0.05) between the two groups were both significant. In group B, the mean time interval between phacovitrectomy and IOL implantation (TV-I) was 25.2 ± 6.9 weeks, and the absolute values of both IOL tilt and decentration were positively correlated with TV-I. In phacovitrectomy for macula-off RRD repair, primary IOL implantation leads to a postoperative myopic shift, while delayed IOL implantation may cause greater IOL tilt and decentration.

Refractive errors in patients with Bardet Biedl syndrome

ABSTRACT Purpose Bardet-Biedl Syndrome (BBS) is a rare autosomal recessive ciliopathy. Within corneal development, primary cilia serve a critical role. We sought to investigate the association of BBS with corneal astigmatism among a cohort of patients with BBS. Methods This was a cross-sectional, retrospective study performed at a pediatric ophthalmology department of a tertiary hospital. The study enrolled 45 patients with genetically confirmed Bardet-Biedl syndrome, encompassing a total of 90 eyes observed from February 2011 to August 2021. Spherical and cylindrical refractive errors and keratometry outcome measures, including diopter (D) values at the flattest and steepest axes, were recorded. Corneal astigmatism of greater than 3D is considered extreme corneal astigmatism based on previously published data. Results Among 45 patients (M:26; F:19), the mean age was 16.4 ± 8.2 years, and the mean best-corrected visual acuity was 20/60. The most common molecular diagnosis was BBS1, seen in 24 of 45 (53.3%). Among all the patients, the mean spherical refractive error was −2.9 ± 3.8D. The mean cylindrical refractive error was 2.6 ± 1.5D. The mean keratometry values at the flattest axis was 43.5 ± 5.3D (39.4–75.0) and at the steepest axis was 47.2 ± 7.3D(41.5–84.0). Among all the patients with BBS, the mean corneal astigmatism was 3.7 ± 1.0D(0.5–7.1), which is considered extreme. Conclusion A cohort of individuals with BBS demonstrated high corneal astigmatism. These results suggest an association between corneal astigmatism and primary ciliary dysfunction and may assist in clinical management and future therapeutic targets among BBS and other corneal disorders.

A new look at the myopia control efficacy of orthokeratology

PurposeTo evaluate the efficacy of orthokeratology contact lens wear in slowing the axial elongation of the eye in myopic children. MethodsData from three prospective studies, which evaluated the use of orthokeratology for slowing myopia progression in children in comparison to a parallel control group of distance, single-vision spectacle lens wearers over a 2-year period, were pooled together for analysis. ResultsCollectively, data from 125 orthokeratology and 118 control subjects were analyzed in this study. Of these, 101 (81 %) and 88 (75 %) orthokeratology and control subjects completed the 2-year follow-up period, respectively. Statistically significant differences in the change in axial length from baseline were found over time, between groups and for the time*group interaction (all p < 0.001), indicating that the rate of increase in axial length over time was significantly lower in the orthokeratology versus the control group. The lower axial elongation of the orthokeratology versus the control group was statistically significant at all time points (all p < 0.001), with significant differences being also present between each of the different pairs of time points (all p < 0.001). The interactions of group with age, gender, mean spherical refractive error and ethnicity at baseline were not significant (p > 0.05). The change in axial length at the 2-year visit in comparison to baseline for the orthokeratology and control groups were 0.41 ± 0.25 and 0.65 ± 0.30 mm, respectively, thus providing a treatment effect following 2-years of lens wear of 0.24 mm (95 % confidence intervals: 0.15 to 0.34 mm). About 40 % and 25 % of the orthokeratology subjects experienced remarkably low and high levels of myopia progression, respectively (2-years axial elongation: ≤0.30 mm and >0.59 mm, respectively). ConclusionsOrthokeratology lens wear slows the axial elongation of the eye in comparison to spectacle lens wear in myopic children. The use of these lenses for slowing myopia progression appears to be very effective and not effective at all in 40% and 25% of orthokeratology lens wearers, respectively.

Prediction of Visual Acuity in Pseudophakic Cataract Population Based on Residual Refraction

Purpose The purpose of the study was to design a simple, handy prediction for the effect of spherical and cylindrical refractive error on the visual acuity degradation at different distances and validate this model on a clinical dataset. Methods This study examined 70 eyes from 35 patients’ post-cataract surgery with aberration-free intraocular lenses. Biometric and corneal data were analysed, and subjective refraction and visual acuity were evaluated by two experienced optometrists. The study computed the spherical equivalent (SEQ), and defocus equivalent via vector addition (DEQ vec), as the sum of absolute values (DEQ abs). Predictive models were developed using univariate regression, with confidence intervals (BCa 95%) calculated through non-parametric bootstrapping (10,000 cycles). Results Various calculated equivalents included −0.44 D for spherical equivalent (SEQ), 0.70 D for defocus equivalent based on vector calculation (DEQ vec), and 0.89 D for defocus equivalent based on absolute values (DEQ abs). Uncorrected and corrected visual acuity averaged 0.07 logMAR and −0.04 logMAR, respectively. The absolute defocus equivalent (DEQ abs) exhibited the smallest confidence interval (BCa 95%) at 0.07. Conclusion The defocus equivalent based on the addition of absolute values (DEQ abs) emerged as the most practical predictor for the described applications. Notably, it offers the advantage of easy calculability through a simple equation: VA loss = DEQ abs ⋅ 0.23. In 95% of cases, this predicted loss would have an accuracy of ±0.03 lines.

Assessing neophyte response to daily disposable silicone hydrogel contact lenses: A randomised clinical trial investigation over one month.

This randomised clinical trial assessed the impact on symptoms, tear film dynamics and ocular surface integrity of daily disposable silicone-hydrogel contact lenses (CLs) over a month, paying special attention to lid wiper epitheliopathy (LWE) and its implications for CL discomfort. Neophyte CL wearers (n = 44, 21.09 ± 5.00 years old) were randomly assigned to either the experimental (n = 24) or control group (n = 20). Participants assigned to the experimental group were required to wear daily disposable CLs for 1 month for at least 8 h/day and 6 days/week. All participants were healthy subjects (no history of ocular surgery or active ocular disease) with spherical refractive errors between -8.00 and +5.00 D and cylindrical power <0.75 D. At the baseline and 1-month sessions, the Dry Eye Questionnaire 5 (DEQ-5) was completed, together with the measurement of tear film osmolarity with the TearLab osmometer, tear meniscus height (TMH) and lipid layer pattern (LLP) using a slit-lamp with Tearscope Plus attached, fluorescein break-up time (FBUT), maximum blink interval (MBI), corneal staining with fluorescein under cobalt blue light and LWE with lissamine green under slit lamp and halogen white light. At the baseline session, LWE showed a negative correlation with DEQ-5 (r = -0.37, p = 0.02). Significant differences in FBUT and LWE (p = 0.04) and a positive correlation between LWE and DEQ-5 (r = 0.49, p = 0.007) were observed at 1 month. Intrasession analysis at 1 month showed significant differences between the experimental and control groups in DEQ-5, FBUT and LWE (all p ≤ 0.02). Intersession analysis in the experimental group showed variations in DEQ-5, FBUT and LWE (all p ≤ 0.02) but no significant variation in the control group (all p ≥ 0.11). The presence of LWE was significantly correlated with higher symptom values in the DEQ-5. Also, participants in the experimental group presented higher values of LWE after 1 month of CL wear, in comparison with the control group.

Ocular Manifestation of the Pediatric Age Group in Almarj

Children are disproportionately affected by visual disorders like refractive errors, amblyopia, and strabismus. Early intervention and vision screening are crucial. The study aims to investigate the ocular manifestation among children of the age group 4–15 years. A cross-sectional study conducted at Marj Teaching Hospital in 2024 examined 100 children with ophthalmological conditions. The examinations included slit lamp examinations, visual acuity assessments, spherical refractive error measurements, and dilated retinal exams. The study examined children aged 4-15 years old, with 59% being male and 43% female. Diagnosis revealed a range of ocular conditions, with astigmatism being the most common at 48%. There were significant differences in visual acuity between males and females (p&lt;0.001), particularly in left eye visual acuity without glasses. There was no significant difference in visual acuity between age groups when wearing or not wearing glasses. However, there was a trend towards better right-eye visual acuity for children aged 4-10 years compared to those aged 11-15 years (p&lt;0.001). Refractive errors with a higher prevalence of simple astigmatism in females compared to males. High hypermetropia was only present in females, suggesting some differences in refractive errors between males and females, particularly hypermetropia. The study emphasizes the significance of regular eye examinations for detecting and addressing visual impairments, and calls for further research into factors contributing to these conditions, particularly male-female differences, to improve eye health and quality of life. we highly advocate assessing the visual acuity of preschool children in order to prevent amblyopia.

Comparison of Spot Vision Screener and Tabletop Autorefractometer with Retinoscopy in the Pediatric Population.

Determining the accuracy of cycloplegic refractive error measurements made with the Spot Vision Screener (SVS, Welch Allyn Inc, Skaneateles Falls, NY, USA) is important for refractive assessment of uncooperative patients during optometric examinations. This study compared cycloplegic refractive errors measured by SVS and tabletop autorefractometer to cycloplegic retinoscopy in children. Eighty-eight eyes of 44 subjects were examined in the study. Refractive error measurements were obtained under cycloplegia using retinoscopy, SVS, and Nidek ARK-530 tabletop autorefractometer (ARK-530, Nidek, Japan). Spherical and cylindrical values, spherical equivalents (SE), and Jackson cross-cylinder values at axes of 0° (J0) and 45° (J45) were recorded. Correlations between methods were analyzed using intraclass correlation coefficient (ICC) and Bland-Altman analysis. The mean age was 7 years (range: 6 months-17 years). Sixteen (36%) of the subjects were female and 28 (64%) were male. For SE there was excellent agreement between retinoscopy and SVS (ICC: 0.924) and between retinoscopy and tabletop autorefractometer (ICC: 0.995). While there was a moderate correlation between retinoscopy and SVS for cylindrical values (ICC: 0.686), excellent correlation was detected between retinoscopy and autorefractometer (ICC: 0.966). J0 and J45 crosscylinder power values were not correlated between retinoscopy and SVS (ICC: 0.472) or retinoscopy and tabletop autorefractometer (ICC: 0.442). Retinoscopy was correlated with both SVS and tabletop autorefractometer for all parameters within ±1.96 standard deviations in Bland-Altman analysis. Cycloplegic retinoscopy is the gold standard for refractive error measurement in the pediatric population. However, it requires time and experienced professionals. This study revealed moderate to good agreement between SVS and retinoscopy, with better agreement in spherical errors than cylindrical errors. Although the SVS is intended for screening programs, it may also be useful in the pediatric eye office to estimate spherical refractive error in uncooperative patients.

Higher order aberrations according to spherical, and astigmatic refractive errors in children

ABSTRACT Clinical relevance The results of this study present novel insights into the impact of spherical and astigmatic refractive errors on overall, corneal and internal aberrations and may provide a clear understanding of the emmetropisation process and the development of visual function. Background This study aimed to assess the association between overall, corneal and internal higher-order aberrations and the spherical and astigmatic components (magnitude and angle) of refractive error in a large sample of children. Methods A total of 311 children aged 7 – 8 years old were classified based on spherical equivalent refraction (myopic, emmetropic and hyperopic); magnitude of astigmatism (none, low and moderate); and angle of astigmatism (with-the-rule, against-the-rule and oblique). Refractive error and overall, corneal and internal higher-order aberrations were measured using the OPD-Scan III workstation. Results Regarding spherical equivalent refraction, myopic eyes had greater root mean square (RMS) overall higher-order values, total spherical, tetrafoil and secondary astigmatism aberrations, and internal higher-order, total spherical and tetrafoil aberrations in comparison to emmetropic eyes. The magnitude of astigmatism was positively associated with all overall RMS aberrations and with internal higher order, coma, total coma, total spherical and tetrafoil aberrations. Eyes with with-the-rule astigmatism showed higher RMS values of coma and total coma compared to eyes with against-the-rule and oblique astigmatism. Conclusions Higher-order aberrations are dependent on the spherical as well as astigmatic components of refractive error. These findings enhance the current understanding of the emmetropisation process and visual function development.

Congenital Stationary Night Blindness: Structure, Function and Genotype–Phenotype Correlations in a Cohort of 122 Patients

To examine the molecular causes of Schubert-Bornschein (S-B) congenital stationary night blindness (CSNB), clinically characterize in detail, and assess genotype-phenotype correlations for retinal function and structure. Retrospective, longitudinal, single-center case series. One hundred twenty-two patients with S-B CSNB attending Moorfields Eye Hospital, United Kingdom. All case notes, results of molecular genetic testing, and OCT were reviewed. Molecular genetics, presenting complaints, rates of nystagmus, nyctalopia, photophobia, strabismus, color vision defects and spherical equivalent refraction (SER). Retinal thickness, outer nuclear layer (ONL) thickness, and ganglion cell layer+ inner plexiform layer (GCL+IPL) thickness from OCT imaging. X-linked (CACNA1F and NYX) and autosomal recessive (TRPM1, GRM6, GPR179 and CABP4) genotypes were identified. The mean (± standard deviation) reported age of onset was 4.94 ± 8.99 years. Over the follow-up period, 95.9% of patients reported reduced visual acuity (VA), half had nystagmus, and 64.7% reported nyctalopia. Incomplete CSNB (iCSNB) patients more frequently had nystagmus and photophobia. Nyctalopia was similar for iCSNB and complete CSNB (cCSNB). Color vision data were limited but more defects were found in iCSNB. None of these clinical differences met statistical significance. There was no significant difference between groups in VA, with a mean of 0.46 logarithm of the minimum angle of resolution, and VA remained stable over the course of follow-up. Complete congenital stationary night blindness patients, specifically those with NYX and TRPM1 variants, were more myopic. CACNA1F patients showed the largest refractive variability, and the CABP4 patient was hyperopic. No significant differences were found in OCT structural analysis during the follow-up period. Retinal structure in CSNB is stationary and no specific genotype-structure correlates were identified. Visual acuity seems to be relatively stable, with rare instances of progression. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Early cataract surgery and affordable Sinskey hook goniotomy in Black and Afro-Latino glaucoma patients: a 6-month retrospective study.

The purpose of this study was to determine the real-world efficacy of early phacoemulsification cataract surgery and goniotomy with a Sinskey hook in patients with glaucoma. This study was conducted at Advanced Eye Care of New York, a private practice located in Manhattan, NY. This was a single-center, retrospective study of predominantly Black and Afro-Latino patients with glaucoma. These patients underwent early phacoemulsification cataract surgery and goniotomy using an affordable and reusable straight Sinskey hook (Ambler 200-μm tip). Patients who underwent the aforementioned procedure with 6 months of follow-up were included in this study. Investigated parameters were intraocular pressure, number of medications, mean deviation on visual field test, visual acuity, adverse events, and pre/postoperative spherical refractive error. Among all 38 eyes that were enrolled in the study and underwent surgery (goniotomy using a Sinskey hook with phacoemulsification), mean intraocular pressure was reduced from 16.45 mmHg at baseline to 13.24 mmHg at month 6, a 19.5% reduction. The mean number of topical intraocular pressure-lowering medications used was reduced from 1.81 at baseline to 0.52 at month 6, a 71% reduction in topical medications. Combined early cataract surgery and goniotomy performed with a Sinskey hook is an affordable microinvasive surgery and an effective way to reduce intraocular pressure and the number of ocular hypertensive medications used in Black and Afro-Latino patients with primary open-angle glaucoma.

A comparison of visual acuities obtained following biometry measurements by contact and immersion A-scan techniques

Objectives: This study aimed to obtain and compare ocular biometry measurements in terms of axial length, anterior chamber depth, and lens thickness by contact and immersion ultrasound techniques of A-scan and compare postoperative results in terms of visual acuity and spherical refractive error obtained by each of these techniques. Materials and Methods: This study was a prospective cohort and a comparative study that was done on 188 eyes under evaluation for cataract surgery. Out of these, 94 eyes were evaluated for biometry measurements using the immersion technique, and the rest were evaluated using the contact technique. Intraocular lens (IOL) powers were calculated using each of the above biometry parameters, and postoperative visual outcomes were obtained in terms of visual acuity and spherical refractive error. Results of demographic, clinical, and biochemical characteristics were expressed as range, mean, and median. For qualitative data, the Chi-square test and for comparison, Students’ unpaired t-tests were used. TAQhe statistical software SPSS Statistics was used to analyze the data. Microsoft Office Word and Excel 2019 were used to generate graphs and tables. P&lt;0.05 was considered as significant. Results: Visual acuity was significantly better in the patients who underwent IOL implantation whose power was calculated by the immersion method on the 1st postoperative day. However, there was no significant difference in the final corrected visual acuity. Spherical refractive error at the end of 1 month was significantly greater in patients who underwent IOL power calculation by the contact method as compared to the immersion method. Conclusion: The immersion method of A-scan gives a lesser refractive error postoperatively and is a more precise method of biometry, though there is no difference in the final visual acuity obtained by either of these methods.

Comparability of Measurement of Astigmatism between URk-800F Auto Refracto-keratometer and MS-39 Anterior Segment Optical Coherence Tomography in Patients with Refractive Error.

Accurate refractive error assessment is the first and the most important step of ocular examination. A reliable screening method of refractive status is important for early detection and prevention of blinding complications of uncorrected refractive error. To evaluate the comparability of astigmatism measured by an auto-refractometer (URk-800F) with the measurements of the gold standard anterior segment optical coherence tomography (AS-OCT). This cross-sectional observational study was conducted in a tertiary eye centre in Kathmandu from February 2023 to June 2023. A total of 100 patients with best corrected visual acuity of ≥ 20/20, spherical refractive error with cylindrical error of more than and equal to -0.75 and no pathology detected on slit lamp examination were taken by consecutive sampling method. Ethical approval was taken for the study. The data were entered into Microsoft Excel and analysed using Bland-Altman analysis. The mean cylindrical power and axis was -2.33 D and 88 degrees for the right eye and -2.32 D and 122 degrees for the left eye respectively, as measured by MS-39 AS-OCT. For URK 800-F Auto-refracto Keratometer, the mean cylindrical power and axis was -2.31 D and 89 degrees for the right eye and -2.27 D and 124 degrees for the left eye. The findings of this study conclude that an auto-refractometer can be used as an effective tool for identification of spherical refractive error as well as measurement of accurate cylindrical power and cylindrical axis in low resource primary care settings.

Asymmetric All-Femtosecond Laser–Cut Corneal Allogenic Intrastromal Ring Segments

Purpose: To describe a novel technique for cutting asymmetric allogenic segments using the femtosecond laser for the management of cases of keratoconus with non-coinciding astigmatism and coma axes. Methods: Four eyes of 2 patients with irregular keratoconus and asymmetric allogenic segments were included. Visual, refractive, tomographic, and aberrometric outcomes, and optical coherence tomography (OCT) sections were measured preoperatively and 6 months postoperatively. Evaluations included slit-lamp examination, manifest refraction, uncorrected (UDVA) and corrected (CDVA) distance visual acuity, and simulated and maximum anterior keratometry (Kmax) using anterior segment OCT. Results: Spherical and cylindrical refractive errors decreased from −2.38 ± 2.96 and −2.94 ± 2.16 to −1.81 ± 2.77 ( P = .04) and −1.75 ± 2.07 ( P = .01) diopters (D), respectively, 6 months postoperatively. There was an average gain of three lines of CDVA. Kmax decreased from 50.02 ± 1.99 to 47.89 ± 3.05 D (P= .03) and coma from 1.05 ± 0.21 to 0.21 ± 0.19 D ( P = .01). Conclusions: Asymmetric femtosecond laser–cut allogenic segments allow a higher level of customization based on size, shape, and arc length, in contrast to the limited range of available synthetic asymmetrical segments. [ J Refract Surg . 2023;39(12):856–862.]

Influencing factors of visual prognosis in patients with persistent submacular fluid after successful scleral buckle surgery for macula-off retinal detachment

Objective: To investigate the factors influencing visual outcomes in patients with rhegmatogenous retinal detachment (RRD) who developed persistent submacular fluid (PSF) after scleral buckling surgery. Methods: A retrospective case series analysis was conducted. Clinical data were collected from patients who underwent successful scleral buckling surgery for RRD at Beijing Tongren Hospital from June 2020 to December 2022 and were followed up. Patients with RRD involving the macular area preoperatively and graded as C1 or below in proliferative vitreoretinopathy (PVR) were included. Surgical procedures followed a minimally invasive scleral buckling approach. PSF was defined as subretinal fluid persisting for more than 1 month postoperatively. Regular follow-up visits were scheduled at postoperative days 1, 3, 7, 2 weeks, and 1 month, followed by monthly visits until complete PSF absorption. Best-corrected visual acuity (BCVA), intraocular pressure, refractive error, slit-lamp biomicroscopy, binocular indirect ophthalmoscopy, and optical coherence tomography (OCT) were performed at each follow-up time point. Eyes were divided into two groups based on whether the final follow-up BCVA was≥0.5 and whether the absorption time of PSF was>6 months, and statistical analysis was performed using the Wilcoxon signed-rank test, chi-squared test, and Mann-Whitney U test. Results: A total of 46 patients (46 eyes) were included in this study, comprising 25 males and 21 females, with a median age of 32.5 (21.0, 57.3) years. The preoperative equivalent spherical refractive error was (-5.27±4.05) D, and the preoperative duration of illness was 30 (14, 92) days. The preoperative BCVA (logarithm of the minimum angle of resolution,logMAR) was 2.00 (1.00, 2.50). Scleral buckle surgery was performed in 28 eyes (60.9%), and 18 eyes (39.1%) underwent scleral buckle surgery combined with encircling. External drainage was performed in 15 eyes (32.6%), while 31 eyes (67.4%) had no external drainage. BCVA (logMAR) at 1 month, 3 months, and the final follow-up postoperatively was 0.60 (0.50, 1.00), 0.40 (0.28, 0.53), and 0.15 (0.00, 0.50), respectively. In the final follow-up, 31 eyes (67.4%) achieved BCVA≥0.5, and 26 eyes (56.5%) had continuous ellipsoid zone on OCT. The differences in BCVA (logMAR) between preoperative, 1 month, 3 months, and the final follow-up were statistically significant (Z=-5.85, -5.63, -4.73;all P<0.001). The absorption time of PSF postoperatively was 6.50 (3.00, 9.00) months, ranging from 2 to 19 months. The eyes with PSF duration<3 months, 3-6 months, and>6 months were 12 eyes (26.1%), 11 eyes (23.9%), and 23 eyes (50.0%), respectively. There were statistically significant differences between the two groups in preoperative BCVA≥0.05, preoperative duration of illness within 1 month, PVR grading, surgical method, and continuous ellipsoid zone on OCT (all P<0.05), while there were no statistically significant differences between the two groups in PSF absorption time, different types of PSF, and intraoperative drainage (all P>0.05). The PSF absorption time in the two groups was 7 (3, 10) months and 6 (4, 8) months, with no statistically significant difference (P>0.05). Conclusions: Preoperative visual acuity, duration of illness, and PVR grading are factors influencing visual outcomes in patients with RRD who have undergone scleral buckling surgery and develop PSF. In contrast, intraoperative drainage, PSF absorption time, and different PSF types are not factors affecting visual prognosis. Although PSF may persist for a long time after scleral buckling surgery, it does not significantly impact long-term visual outcomes.

Whole-Exome Sequencing of 21 Families: Candidate Genes for Early-Onset High Myopia.

High myopia is the most severe and pathological form of myopia. It occurs when the spherical refractive error exceeds -6.00 spherical diopters (SDs) or the axial length (AL) of the eye is greater than 26 mm. This article focuses on early-onset high myopia, an increasingly common condition that affects children under 10 years of age and can lead to other serious ocular pathologies. Through the genetic analysis of 21 families with early-onset high myopia, this study seeks to contribute to a better understanding of the role of genetics in this disease and to propose candidate genes. Whole-exome sequencing studies with a panel of genes known to be involved in the pathology were performed in families with inconclusive results: 3% of the variants found were classified as pathogenic, 6% were likely pathogenic and the remaining 91% were variants of uncertain significance. Most of the families in this study were found to have alterations in several of the proposed genes. This suggests a polygenic inheritance of the pathology due to the cumulative effect of the alterations. Further studies are needed to validate and confirm the role of these alterations in the development of early-onset high myopia and its polygenic inheritance.

Refractive errors in infants with retinopathy of prematurity treated using laser or anti-vascular endothelial growth factor monotherapy

Background: Infants treated for retinopathy of prematurity (ROP) could develop visually significant refractive errors. In this study, we report pre-treatment refractive errors in premature infants with treatment-requiring ROP treated using laser or anti-VEGF monotherapy and compare the components of post-treatment refractive error values between the two treatment groups at different follow-up timepoints.&#x0D; Methods: In this retrospective cohort study, we analyzed 360 eyes of 181 premature infants with treatment-requiring ROP who were referred to Farabi Eye Hospital, Tehran, Iran between March 2020 and April 2021. Of the 360 eyes, 195 received laser monotherapy (laser treatment group) and 165 received an intravitreal anti-VEGF injection (anti-VEGF therapy group). All included eyes underwent pre- and post-treatment cycloplegic refraction. Cycloplegia was induced for each infant by instilling a mixed eye drop containing 1% tropicamide, 2.5% phenylephrine, and 0.5% tetracaine (in equal volumes) in each eye three times at five-minute intervals. Cycloplegic refraction was performed 30 minutes after the third instillation.&#x0D; Results: The mean (standard deviation [SD]) gestational age (GA) and birth weight (BW) of the infants were 29.0 (2.0) weeks and 1241.0 (403.0) g, respectively. The male-to-female ratio in the entire study cohort was 107 (59.1%) / 74 (40.9%), whereas the ratios in the anti-VEGF therapy group and laser treatment group were 47 (56.6%) / 36 (43.4%) and 60 (61.2%) / 38 (38.8%), respectively. The pre-treatment assessment revealed that 218 (60.6%) eyes were hyperopic, 112 (31.1%) were myopic, and 30 (8.3%) were emmetropic. In the anti-VEGF therapy group, 87 (52.7%) eyes were hyperopic, 63 (38.2%) were myopic, and 15 (9.1%) were emmetropic. In the laser treatment group, 131 (67.2%) eyes were hyperopic, 49 (25.1%) were myopic, and 15 (7.7%) were emmetropic. The mean (SD) spherical refractive error and spherical equivalent of refractive error (SEQ) at the 1-week, 1-month, and &gt; 6-month post-treatment follow-up timepoints; the mean cylindrical refractive error at the 3-month post-treatment timepoint; and the mean SEQ at the time of ROP regression were significantly different between the treatment groups (all P &lt; 0.05). The rate of anisometropia increased significantly from 3.4% at baseline to 9.2% at the 6-month post-treatment follow-up timepoint (P &lt; 0.05).&#x0D; Conclusions: In this study, the most common pre-treatment refractive status of all included eyes with treatment-requiring ROP and eyes in each treatment group was hyperopia, followed by myopia and emmetropia. At the more than 6-month post-treatment follow-up, cycloplegic refraction revealed that the laser-treated eyes were significantly more hyperopic than the anti-VEGF-treated eyes, a finding similar to the pre-treatment refraction results. Further studies of same cohort with a longer follow-up period and a control group are needed to determine the real-world effect of each treatment modality on the refractive statuses of children treated for ROP.

Correlation between anterior chamber depth changes and post operative refractive error after phacoemulsification

: There is an increase in patient demands and satisfaction with post-operative visual recovery. There are numerous factors affecting post-operative visual outcomes. One of the factors is the change in anterior chamber depth post-operatively. The following study was planned to assess the changes in anterior chamber depth post- operatively and determine the correlation with post-operative refractive errors in patients who had cataracts and underwent phacoemulsification with intraocular lens (IOL) implantation. : This prospective cohort study was conducted in 120 eyes. The cases diagnosed with cataract underwent phacoemulsification. Preoperative and post-operative anterior chamber depths were obtained and post-operative spherical equivalent of refractive errors were noted at 4 weeks.: Smaller anterior chamber depths had a larger amount of deepening of the anterior chamber (ACD difference&amp;#62;1.22mm) after cataract surgery and vice versa (r= -0.46, p&amp;#60;0.01). Post-operative refractive error showed hyperopic shift when the change in AC depth was small (&amp;#60;1.22mm) and myopic shift when the change in AC depth was large (&amp;#62;=1.22mm). : There is a definite correlation between AC depth difference and post-operative spherical refractive error (r= -0.41, p&amp;#60;0.01).