Association Between Preoperative Ocular Parameters and Myopic Shift in Children Undergoing Primary Intraocular Lens Implantation.

Purpose: To evaluate the association between preoperative ocular parameters and myopic shift following primary intraocular lens (IOL) implantation in pediatric cataracts. Methods: Eyes from pediatric patients undergoing bilateral cataract surgery with primary IOL implantation were included. Eyes were grouped by age at surgery and subdivided into three axial length (AL) subgroups and three keratometry subgroups. Mixed-effects linear regression was utilized to assess the trend in myopic shift among subgroups. Multivariable analysis was performed to determine factors associated with myopic shift. Results: A total of 222 eyes were included. The median age at surgery was 4.36 years (interquartile range [IQR], 3.16-6.00 years) and the median follow-up was 4.18 years (IQR, 3.48-4.64 years). As preoperative AL increased, a decreased trend was observed in myopic shift and rate of myopic shift (P = 0.008 and P = 0.003, respectively, in the 4 to <6 years old group; P = 0.002 and P < 0.001, respectively, in the ≥6 years old group). Greater myopic shift and rate of myopic shift were associated with younger age at surgery (P = 0.008 and P = 0.008, respectively). Both myopic shift and rate of myopic shift were negatively associated with AL. Conclusions: Age at surgery and preoperative AL were associated with myopic shift in pediatric cataracts following primary IOL implantation. Adjusting the target refraction based on preoperative AL could potentially improve patients' long-term refractive outcome. Translational Relevance: This study may help to guide the selection of postoperative target refraction according to age at surgery and preoperative ocular parameters for pediatric cataracts.

Fundus Tessellation and Parapapillary Atrophy, as Ocular Characteristics of Spontaneously High Myopia in Macaques: The Non-Human Primates Eye Study.

Purpose: This study aimed to evaluate the ocular characteristics associated with spontaneously high myopia in adult nonhuman primates (NHPs). Methods: A total of 537 eyes of 277 macaques with an average age of 18.53 ± 3.01 years (range = 5-26 years), raised in a controlled environment, were included. We measured ocular parameters, including spherical equivalent (SE), axial length (AXL), and intraocular pressure. The 45-degree fundus images centered on the macula and the disc assessed the fundus tessellation and parapapillary atrophy (PPA). Additionally, optical coherence tomography (OCT) was used to measure the thickness of the retinal nerve fiber layer (RNFL). Results: The mean SE was -1.58 ± 3.71 diopters (D). The mean AXL was 18.76 ± 0.86 mm. The prevalence rate of high myopia was 17.7%. As myopia aggravated, the AXL increased (r = -0.498, P < 0.001). Compared with non-high myopia, highly myopic eyes had a greater AXL (P < 0.001), less RNFL thickness (P = 0.004), a higher incidence of PPA (P < 0.001), and elevated grades of fundus tessellation (P < 0.001). The binary logistic regression was performed, which showed PPA (odds ratio [OR] = 4.924, 95% confidence interval [CI] = 2.375-10.207, P < 0.001) and higher grades of fundus tessellation (OR = 1.865, 95% CI = 1.474-2.361, P < 0.001) were independent risk characteristics for high myopia. Conclusions: In NHPs, a higher grade of fundus tessellation and PPA were significant biomarkers of high myopia. Translational Relevance: The study demonstrates adult NHPs raised in conditioned rooms have a similar prevalence and highly consistent fundus changes with human beings, which strengthens the foundation for utilizing macaques as an animal model in high myopic studies.

Corneal Endothelial Morphology and Ocular Biometric Indexes in Premature Children With and Without Retinopathy of Prematurity.

Purpose: The purpose of this study was to analyze human corneal endothelial cells (HCECs) morphology and ocular biometrics in premature (PM) children with or without retinopathy of prematurity (ROP). Methods: Retrospective data on patient demographics, HCECs status, and ocular biometrics with at least 2 visits between 2016 and 2021 were reviewed. The main outcomes were endothelial cell density (ECD), coefficient of variation (CV), hexagonal cell ratio (HEX), central corneal thickness (CCT), axial length, anterior chamber depth, keratometry, corneal diameter, pupil diameter, and refraction status. Generalized estimating equation was used to evaluate the differences between PM no-ROP and ROP groups. We also analyzed the trend of ECD, CV, HEX, and CCT change with age between groups. Results: The study included 173 PM patients without ROP and 139 patients with ROP. A total of 666 and 544 measurements were recorded in the PM no-ROP and ROP groups, respectively. The ROP group had higher spherical power, myopic spherical equivalent (SE), and steeper steep keratometry (K; P < 0.05). The ROP group had higher CV (P = 0.0144), lower HEX (P = 0.0012) and thicker CCT (P = 0.0035). In the HCECs parameters, the ROP group had slower ECD decrement (P < 0.0001), faster CV decrement (P = 0.0060), and faster HEX increment (P = 0.0001). A difference in corneal morphology changes between the ROP and PM no-ROP groups were prominent in patients with lower gestational age (GA) in the subgroup analysis. Conclusions: Worse HCECs morphology and higher myopic status were initially observed in patients with prior ROP but not in PM patients with no-ROP. ECD and HCECs morphology improved with age, especially in patients with low GA.

Investigation of the myopic outcomes of the newer intraocular lens power calculation formulas in Korean patients with long eyes.

This study investigated the underlying causes of the myopic outcomes of the optic-based newer formulas (Barrett Universal II, EVO 2.0, Kane, Hoffer-QST and PEARL-DGS) in long Korean eyes with Alcon TFNT intraocular lens (IOL) implantation. Postoperative data from 3100 randomly selected eyes of 3100 patients were analyzed to compare the reference back-calculated effective lens positions (ELPs) based on the Haigis formula using conventional axial length (AL) and Cooke-modified AL (CMAL) with the predicted ELP of each single- and triple-optimized Haigis formula applied to AL- and CMAL. Contrary to the AL-applied Haigis formula, the predicted ELP curve of the CMAL-applied, single-optimized Haigis formula, simulating the methods of the newer formulas, exhibited a significant upward deviation from the back-calculated ELP in long eyes. The relationship between the AL and anterior chamber depth in our long-eyed population differed from that in the base population of the PEARL-DGS formula. The myopic outcomes in long eyes appeared to stem from the substantial overestimation of the postoperative IOL position with AL modification, leading to the implantation of inappropriately higher-powered IOLs. This discrepancy may be attributed to the ethnic differences in ocular biometrics, particularly the relatively smaller anterior segment in East Asian patients with long AL.

[Correlation between refraction and axial length in Albinos]. / Corrélation entre la réfraction et la longueur axiale du sujet Albinos.

PURPOSE: To investigate the relationship between refraction and ocular axial length in albinos. PATIENTS AND METHODS: A cross-sectional, analytical study was carried out from June to November 2021 at the Central Hospital of Yaounde (Cameroon), which included consenting albino subjects aged over 15years. All subjects underwent visual acuity testing, axial length measurements and objective refraction under cycloplegia. RESULTS: We included 51 albino subjects. The mean age was 26.06±9.47years, and the sex ratio was 0.5. Type 2 oculocutaneous albinism (OCA2) was predominant, representing 82.4% of cases. The mean uncorrected visual acuity was 0.93±0.25 logMAR, and the most common ametropia was myopic astigmatism (52.9%). The mean axial length was 24.65±2.54mm with extremes of 21.54 and 30.33mm. Eyes with myopia and myopic astigmatism had significantly longer axial lengths than those with hyperopic and mixed astigmatism. A strong, significant negative correlation (r=-0.93; P˂0.001) between the spherical component of the refraction and axial length was found. CONCLUSION: The spherical component of the refraction decreases significantly with increasing axial length in albinos.

Longitudinal Changes in Refractive Development in Highly Hyperopic Children: A 2.6-11.2 Year Follow-up of Preschoolers Diagnosed with High Hyperopia.

PURPOSE: This study aims to elucidate the longitudinal refractive and ocular biometric alterations in preschool children with high hyperopia who underwent early interventions. METHODS: We conducted a retrospective analysis of preschool children diagnosed with high hyperopia at Tianjin Medical University Eye Hospital between 2011 and 2023. Inclusion criteria required an initial examination with cycloplegic refraction, bilateral spherical equivalent power (SE) ≥ +5.00D with a difference <1.00D, a minimum two-year follow-up, and at least three ocular biometric measurements. The annual axial growth rate evaluated emmetropization in highly hyperopic children. We applied Restricted Cubic Spline (RCS) models to explore potential nonlinear relationships between age and spherical equivalent, axial length, corneal curvature, and axial length-to-corneal curvature ratio. Additionally, Mixed-effects models were employed to investigate factors associated with changes in refractive error and axial length. RESULTS: The study enrolled 60 eligible subjects, with a median initial diagnosis age of 3.5 years (IQR, 2.8-4.9 years) and a median last visit age of 9.3 years (IQR, 8.1-10.8 years). The average follow-up duration was 5.7 years. RCS analysis revealed notable nonlinear changes in spherical equivalent power, axial length, and axial length-to-corneal curvature ratio, although corneal curvature displayed no statistically significant nonlinear trend. Factors affecting SE changes included the presence of strabismus, the use of cycloplegia, baseline SE, and age. Conversely, changes in axial length solely correlated with baseline axial length and age. CONCLUSION: Highly hyperopic preschool children undergoing early intervention display a marked emmetropization tendency, though most still remain moderately to highly hyperopic, with the progression of refractive changes showing non-uniform patterns with respect to age.

Long-term observation of V4c implantable collamer lenses implantation for moderate to extreme high myopia correction: five years follow-up.

BACKGROUND: This study aims to assess the long term effectiveness, safety, predictability and stability of V4c implantable collamer lenses (ICL) for correction of moderate to extreme high myopia. METHODS: We reviewed 125 eyes from 64 patients who implanted V4c ICL at the Refractive Surgery Center of West China Hospital in Chengdu, China, between May 2015 and January 2017. The median spherical equivalent was -11.50 D (interquartile range [IQR]: -13.00 to -9.00 D). We followed up with the patients over five years and evaluated several parameters, including uncorrected visual acuity (UDVA), corrected visual acuity (CDVA), axial length, refractive error, endothelial cell density (ECD), intraocular pressure (IOP), white-to-white distance (WTW), and vault. We performed a correlation analysis to explore the potential impacts on vault following implantation. RESULTS: The median safety index (postoperative CDVA/preoperative CDVA) during the last follow-up was 1.00 (interquartile range [IQR]: 1.00-1.20), and the efficacy indices (postoperative UDVA/preoperative CDVA) were 1.20 (IQR: 1.00-1.25), 1.20 (IQR: 1.00-1.33), and 0.8 (IQR: 0.65-1.00) at postoperative 1 week, 1 month, and 5 years, respectively. At the five-year mark, 16% of the eyes were within ±0.50 D of expected correction, and 73% were within ±2.00 D. No significant difference in ECD was observed between pre-operative and post-operative measurements. Compared to baseline, we observed a significant increase in IOP at the one-week follow-up, which decreased significantly at the one-month visit. Furthermore, we identified ICL size and spherical equivalent (SE) as independent variables in a multiple linear regression model that accurately predicted the five-year vault after surgery. CONCLUSION: In conclusion, V4c ICL implantation is an effective and safe treatment for moderate to extreme high myopia with good predictability and stability over the long-term.

Tessellated fundus occurs earlier than myopia in children aged 3-6 years.

BACKGROUND/OBJECTIVES: Tessellated fundus can exist in normal healthy eyes. This study aims to evaluate the occurrence and influencing factors of tessellated fundus in preschool children aged 3-6 years. SUBJECTS/METHODS: This kindergarten-based cross-sectional study included 1716 children with an age range of 3-6 years. All participants underwent a comprehensive eye examination and a questionnaire. According to the number of quadrants occupied by tessellated fundus around the optic disc in fundus photographs, it was divided into four grades. RESULTS: 600 (35.0%) children had peripapillary tessellation. According to the spherical equivalent (SE), the subjects were divided into three groups: Hyperopia group (SE > + 0.75D, n = 1194)；Pre-myopia group (-0.50D < SE ≤ + 0.75D, n = 455); Myopia group (SE ≤ -0.50D, n = 67). The proportion of peripapillary tessellated fundus was 33.0%, 38.0%, 50.7% respectively. According to the regression analysis, in the non-myopia group (Pre-myopia group and Hyperopia group), the occurrence of peripapillary tessellated fundus was associated with longer axial length (OR, 1.566; 95% CI: 1.229-1.996, p < 0.001) and larger corneal radius of curvature (OR, 1.837; 95% CI: 1.006-3.354, p = 0.048). However, in Pre-myopia group, the corneal radius of curvature was not associated with the occurrence of peripapillary tessellated fundus (p = 0.830). In Hyperopia group, the corneal radius of curvature was associated with the occurrence of peripapillary tessellated fundus (OR, 2.438; 95% CI: 1.160-5.122, p = 0.019). CONCLUSIONS: The occurrence of peripapillary tessellated fundus is more than 30% in 3-6 year old preschool children. Tessellated fundus can also occur in non-myopic children, and is related to the length of axial length and large radius of corneal curvature.

Bi-Gaussian analysis reveals distinct education-related alterations in spherical equivalent and axial length-results from the Gutenberg Health Study.

PURPOSE: The aim of this study is to investigate the distribution of spherical equivalent and axial length in the general population and to analyze the influence of education on spherical equivalent with a focus on ocular biometric parameters. METHODS: The Gutenberg Health Study is a population-based cohort study in Mainz, Germany. Participants underwent comprehensive ophthalmologic examinations as part of the 5-year follow-up examination in 2012-2017 including genotyping. The spherical equivalent and axial length distributions were modeled with gaussian mixture models. Regression analysis (on person-individual level) was performed to analyze associations between biometric parameters and educational factors. Mendelian randomization analysis explored the causal effect between spherical equivalent, axial length, and education. Additionally, effect mediation analysis examined the link between spherical equivalent and education. RESULTS: A total of 8532 study participants were included (median age: 57 years, 49% female). The distribution of spherical equivalent and axial length follows a bi-Gaussian function, partially explained by the length of education (i.e., < 11 years education vs. 11-20 years). Mendelian randomization indicated an effect of education on refractive error using a genetic risk score of education as an instrument variable (- 0.35 diopters per SD increase in the instrument, 95% CI, - 0.64-0.05, p = 0.02) and an effect of education on axial length (0.63 mm per SD increase in the instrument, 95% CI, 0.22-1.04, p = 0.003). Spherical equivalent, axial length and anterior chamber depth were associated with length of education in regression analyses. Mediation analysis revealed that the association between spherical equivalent and education is mainly driven (70%) by alteration in axial length. CONCLUSIONS: The distribution of axial length and spherical equivalent is represented by subgroups of the population (bi-Gaussian). This distribution can be partially explained by length of education. The impact of education on spherical equivalent is mainly driven by alteration in axial length.

Biometric description of 34 589 eyes undergoing cataract surgery: sex differences.

PURPOSE: To describe gender differences in the biometric parameters of a large sample of patients with cataract. Cataract surgery has evolved from a vision restoration to a refractive procedure, and population-based studies are vital to optimize normative databases and postsurgical outcomes. SETTING: Miguel Servet University Hospital, Zaragoza, Spain. DESIGN: Retrospective single-center observational study. METHODS: The study included 34 589 eyes (20 004 patients with cataract). Biometric data were obtained from IOL Master 700 and Pentacam HR. Linear mixed models were used to account for intereye correlation. HofferQST formula was used to calculate the hypothetical distribution of intraocular lens (IOL) power (arbitrary lens; A = 119.2). RESULTS: Most biometric variables showed significant differences between sexes ( P < .0001), such as 0.53 mm shorter eyes found in females, of which 0.16 mm are explained by shorter aqueous depth. Steeper anterior keratometries (∼0.75 diopter [D]) were found in women, to end up in no difference on anterior astigmatism magnitude, but different orientation ( P < .0001). The distribution of IOL power differed between sexes ( P < .001), with the interquartile range shifting 1 D toward more powerful lenses in women and odds ratio (power >26 D) = 2.26, P < .0001 (Fisher). CONCLUSIONS: Large sample size studies provide smaller margin of error, higher power, and controlled risk of reporting false (negative or positive) findings. Highly significant differences between sexes in ocular biometry were found; this supports the idea that including sex as a parameter in IOL calculation should be explored and may improve results. In addition, the distribution of IOL powers was provided, which may be useful for manufacturers and hospital stock planning.

Effects of reduction in intraocular pressure after trabeculotomy on axial length and intraocular lens selection.

PURPOSE: To investigate the relationship between intraocular pressure (IOP) and axial length (AL) and to compare the refractive predicted error in patients who have undergone cataract surgery alone or in combination with trabeculotomy. SETTING: Hospital. DESIGN: Single-center, retrospective, case-control. METHODS: The medical records of patients who had undergone cataract surgery alone or in combination with trabeculotomy using the Tanito microhook were retrospectively reviewed. Patients were grouped into cataract surgery alone (CAT) or cataract surgery combined with trabeculotomy (LOT) groups. Demographic data, preoperative and postoperative IOP and AL, and surgically induced astigmatism (SIA) were analyzed before and 1 month postoperatively to evaluate the interplay between IOP, AL, and refractive outcomes. RESULTS: 52 eyes (52 patients) underwent LOT, and 67 eyes (67 patients) underwent CAT. The mean IOP at baseline did not differ between the groups; the change in IOP (dIOP) was significantly higher in the LOT group than in the CAT group. The mean AL at baseline and the change in AL (dAL) were 24.0 ± 1.2 mm and 0.16 ± 0.11 mm, respectively, in the LOT group, and 23.8 ± 1.1 mm and 0.11 ± 0.070 mm, respectively, in the CAT group. The difference in dAL was also significant. In the LOT group, dIOP and dAL were significantly correlated. The mean SIA vectors did not significantly differ between the groups. CONCLUSIONS: AL decreased because of the reduction in IOP after cataract surgery combined with trabeculotomy. Consequently, the refractive target error was greater, and the postoperative refractive outcome showed a tendency toward hyperopia.

Refractive predictive errors using Barrett II, Hoffer-Q, and SRKT formulae for pediatric IOL implantation.

PURPOSE: To compare the accuracy of the Barrett II universal (BU II) formula, Hoffer-Q, and SRKT formulae following lensectomy and IOL implantation in a large pediatric cohort. METHODS: Retrospective study of children who underwent lensectomy and IOL implantation between 2015 and 2023 at Hadassah-Hebrew University Medical Center, Jerusalem, Israel. RESULTS: One hundred and fifty-one eyes of 104 children aged 6.0 ± 3.9 years were included. The mean prediction error (PE) was - 0.08 ± 1.54 diopters (D) with BU II, 0.24 ± 1.46 D with Hoffer-Q, and 0.71 ± 1.92 D with SRKT (P = 0.10). In eyes with axial length (AL) < 22 mm, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.024). In eyes with AL ≥ 22 mm, BU II had a smaller PE than Hoffer-Q (P = 0.048). In children 24 months or older at surgery, BU II had a smaller PE than SRKT and Hoffer-Q (P = 0.012). However, in younger children, no difference was found between the formulae (P = 0.61). For mean k-values ≥ 44.5 D, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.002). An absolute prediction error < 1.0 D was obtained with BU II in 66% of eyes and SRKT in 35% (P = 0.01). CONCLUSIONS: The BU II formula performed well with a small prediction error. No significant difference in PE was detected overall between the formulae. However, only BU II demonstrated a stable prediction error at varying axial lengths, K-readings, and ages. As the biometric parameters of the developing eye change with growth, the BU II formula offers a reliable and stable option for pediatric IOL calculation.

Effects of Deep Optic Nerve Head Structures on Bruch's Membrane Opening- Minimum Rim Width and Peripapillary Retinal Nerve Fiber Layer.

PURPOSE: To explore the effects of deep optic nerve head (ONH) structures on Bruch's membrane opening (BMO)-minimum rim width (MRW) and peripapillary retinal nerve fiber layer thickness (pRNFLT) in healthy eyes. DESIGN: Prospective cross-sectional study. METHODS: Two hundred five healthy eyes of 141 subjects (mean ± standard deviation of age and axial length (AXL): 46.9 ± 10.0 years and 24.79 ± 1.15 mm) were enrolled. Best fit multivariable linear mixed models identified factors associated with BMO-MRW and pRNFLT. Explanatory variables included age, gender, AXL, BMO and anterior scleral canal opening (ASCO) area and ovality, magnitude of BMO and ASCO shift, peripapillary choroidal thickness, lamina cribrosa (LC) parameters, prelaminar thickness, and peripapillary scleral (PPS) angle. RESULTS: Thinner BMO-MRW was associated with older age, smaller ASCO/BMO offset magnitude, larger BMO area, thinner prelaminar thickness, deeper LC, and thinner pRNFLT (P = .011, <.001, .004, <.001, <.001, <.001 respectively). Thinner pRNFLT was associated with shorter AXL, smaller ASCO area, a more posteriorly bowed PPS, shallower LC and thinner BMO-MRW. (P = .030, .002, .035, .012, <.001 respectively) CONCLUSIONS: BMO-MRW and pRNFLT were influenced by several deep ONH structures such as BMO and ASCO position shift, BMO or ASCO area, prelaminar thickness, PPS bowing and LC depth in addition to patient characteristics such as age and AXL. The degree and/or direction of associations varied between deep ONH structures and BMO-MRW or pRNFLT. Despite both BMO-MRW and pRNFLT being surrogate parameters for RGC loss, a complex relationship with ONH deep-layer morphology was indicated.

Corneal stress‒strain index in relation to retinal nerve fibre layer thickness among healthy young adults.

BACKGROUND/OBJECTIVES: To determine the relationship between corneal stress-strain index (SSI) and retinal nerve fibre layer (RNFL) thickness. SUBJECTS/METHODS: 1645 healthy university students from a university-based study contributed to the analysis. The RNFL thickness was measured by high-definition optical coherence tomography (HD-OCT), axial length (AL) was measured by IOL Master, and corneal biomechanics including SSI, biomechanical corrected intraocular pressure (bIOP), and central corneal thickness (CCT) were measured by Corvis ST. Multivariate linear regression was performed to evaluate the relationship between the SSI and RNFL thickness after adjusting for potential covariates. RESULTS: The mean age of the participants was 19.0 ± 0.9 years, and 1132 (68.8%) were women. Lower SSI was significantly associated with thinner RNFL thickness ( ß =8.601, 95% confidence interval [CI] 2.999-14.203, P = 0.003) after adjusting for age, CCT, bIOP, and AL. No significant association between SSI and RNFL was found in men, while the association was significant in women in the fully adjusted model. The association was significant in the nonhigh myopic group ( P for trend = 0.021) but not in the highly myopic group. Eyes with greater bIOP and lower SSI had significantly thinner RNFL thickness. CONCLUSIONS: Eyes with lower SSI had thinner RNFL thickness after adjusting for potential covariates, especially those with higher bIOP. Our findings add novel evidence of the relationship between corneal biomechanics and retinal ganglion cell damage.

Clinical outcomes and rotational stability after implantation of a monofocal toric intraocular lens with textured haptics in normal vs high axial lengths.

PURPOSE: To compare the clinical outcomes and rotational stability after implantation of a toric intraocular lens (IOL) with textured haptics in eyes with normal vs high axial lengths (ALs). SETTING: Nethradhama Superspeciality Eye Hospital, Bangalore, India. DESIGN: 2-arm, retrospective comparative study. METHODS: This retrospective study included 114 eyes of 114 patients who underwent femtolaser cataract surgery followed by implantation of the HOYA Vivinex Toric monofocal IOL (Model XY1A-SP), of which 62 and 52 eyes belonged to normal (≤23.9 mm) and high (≥24 mm) AL groups, respectively. 1 week and 3 months postoperatively, clinical outcomes and rotational stability of the toric IOL was evaluated. RESULTS: 3 months postoperatively, % eyes achieving refractive astigmatism accuracy within ≤0.50 diopter, was 100% (n = 62) in the normal vs 94% (n = 49) in the high AL group. All eyes that is, 100% (n = 62) in the normal and 96.15% (n = 50) eyes in the high myopia group were <5 degrees of the intended axis. The mean change in postoperative rotation from 1 week to 3 months was 0.28 ± 0.09 degrees in the normal, and 0.30 ± 1.11 degrees in the high AL group ( P = .80). No significant correlation was observed between AL and white-to-white diameter with 1-week postoperative rotation values. No eye required repositioning of toric IOL for significant misalignment. CONCLUSIONS: No significant differences were observed for clinical outcomes and postoperative rotational stability between eyes with normal and high ALs, suggesting excellent rotational stability of the Vivinex Toric IOL with textured haptics in all eyes, irrespective of the preoperative AL measurements.

Intraocular lens calculation using the ESCRS online calculator in pediatric eyes undergoing lens extraction.

PURPOSE: To evaluate the ESCRS online calculator for intraocular lens (IOL) calculation in children undergoing lens extraction and primary IOL implantation. SETTING: Department of Ophthalmology, Goethe-University Frankfurt, Frankfurt am Main, Germany. DESIGN: Retrospective, consecutive case series. METHODS: Eyes that received phacoemulsification and IOL implantation (Acrysof SN60AT) due to congenital or juvenile cataract were included. We compared the mean prediction error (MPE), mean and median absolute prediction error (MAE, MedAE) of formulas provided by the recently introduced online calculator provided by the ESCRS with the SRK/T formula, as well as the number of eyes within ±0.5 diopters (D), ±1.0 D, ±2.0 D of target refraction. Postoperative spherical equivalent was measured by retinoscopy 4 to 12 weeks postoperatively. RESULTS: 60 eyes from 47 patients with a mean age of 6.5 ± 3.2 years met the inclusion criteria. Mean axial length was 22.27 ± 1.19 mm. Mean preoperative spherical equivalent (SE) was -0.25 ± 3.78 D, and mean postoperative SE was 0.69 ± 1.53 D. The MedAE was lowest in the SRK/T formula (0.56 D, ± 1.03) performed significantly better ( P = .037) than Hoffer QST and Kane, followed by BUII (0.64 D, ± 0.92), Pearl DGS (0.65 D, ± 0.94), EVO (0.69 D, ± 0.94), Hoffer QST (0.75 D, ± 0.99), and Kane (0.78 D, ± 0.99). All of those were significantly above zero ( P < .001). 41 eyes received an intraoperative optic capture (68%). When excluding eyes that did not receive intraoperative optic capture (n = 19; 32%), the MedAE was shown to be lower. CONCLUSIONS: Using modern IOL calculation formulas provided by the ESCRS calculator provides good refractive predictability and compares for most of the formulas with the results with SRK/T. In addition, the formulas seem to anticipate the postoperative refraction better for eyes that receive a posterior optic capture.

Association Between Endothelial Cell Density and Corneal Thickness in Medium, Short, and Long Eyes of Han Chinese Cataract Patients.

PURPOSE: To evaluate the association between the endothelial cell density (ECD) and central corneal thickness (CCT) in medium, short, and long eyes of preoperative Han Chinese cataract patients. DESIGN: Retrospective cross-sectional study. METHODS: We consecutively enrolled 410 eyes, namely, 50 short eyes (axial length [AL]<22.0 mm), 150 medium eyes (22.0≤AL<24.0 mm), 120 medium-long eyes (24.0≤AL<26.0 mm), and 90 long eyes (AL≥26.0 mm), of 410 adult patients scheduled for cataract surgery. The ECD and CCT were determined preoperatively with a noncontact specular microscope. The association between the CCT and ECD was identified by using a multivariable regression analysis. A thin cornea was defined as having a CCT less than 500 µm. RESULTS: After adjusting for age, the presence of arterial hypertension, the presence of diabetes mellitus, intraocular pressure, and AL, a positive association between the CCT and ECD was identified in short eyes (linear regression coefficient [B]=3.40; standardized B [ß]=0.52; P = .03), medium eyes (B = 2.33; ß=0.28; P = .002), medium-long eyes (B = 1.84; ß=0.25; P = .02), and long eyes (B = 2.69; ß=0.41; P = .04). In the total group, the multivariable logistic analysis showed a significant link between the presence of a thin cornea and a lower ECD (odds ratio [OR]=0.80 per 100 cells/mm2 increase; P = .001). CONCLUSIONS: For cataract patients of Han ethnicity, a significant association between a thin CCT and a lower ECD was shown across the AL spectrum and was most prominent in short eyes. Eyes with a thin cornea are more likely to have a lower ECD.

Influence of Lens Thickness on Accuracy of Kane, Hill-RBF 3.0, Barrett Universal II, Emmetropia Verifying Optical, and Pearl-DGS Formulas in Eyes with Nonhigh Myopia and High Myopia.

PURPOSE: To investigate the influence of lens thickness (LT) on accuracy of Kane, Hill-RBF 3.0 Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO), and Pearl-DGS formulas in eyes with different axial lengths (AL). METHODS: The prospective cohort study was conducted at Eye and ENT Hospital of Fudan University. Patients who had uneventful cataract surgery between March 2021 and July 2023 were recruited. Manifest refraction was conducted two-month post-surgery. Eyes were divided into 4 groups based on AL: short (<22mm), medium (22-24.5 mm), medium long (24.5-26mm) and very long (≥26mm). In each AL group, eyes were then divided into 3 subgroups based on the LT measured with IOLmaster700: thin (<4.5 mm), medium (4.5-5.0 mm), and thick (≥ 5 mm). The influence of LT on accuracy of Kane, Hill-RBF 3.0, BUII, EVO, and Pearl-DGS formulas were investigated in each AL group. RESULTS: A total of 327 eyes from 327 patients were analyzed, with 64, 102, 73 and 88 eyes in each AL group, respectively. In eyes with AL < 24.5 mm, myopic PE was significantly associated with greater LT using all the 5 formulas (all p < 0.05). Backward stepwise multivariate regression analyses revealed that LT was an important influencing factor for PE in all 5 formulas, particularly in eyes with AL <24.5 mm. In eyes with AL <24.5 mm and LT > 5.0 mm, PE of all 5 formulas calculated with the optional parameter LT were more myopic than those calculated without LT. CONCLUSIONS: Thicker LT was associated with more myopic PE among eyes with AL <24.5 mm when using all 5 formulas. Further optimization of current formulas is necessary, especially for eyes with short AL and thick LT.

Quantitative analysis of dynamic iris changes in primary angle-closure disease with long axial lengths: the Handan Eye Study.

OBJECTIVE: To investigate dynamic iris changes in patients with primary angle-closure disease (PACD) with long axial length (AL) compared to those with short and medium AL. METHODS: This observational cross-sectional study enrolled participants aged 35 years or older from the Handan Eye Study follow-up examination who were diagnosed with PACD and underwent Visante anterior segment optical coherence tomography (ASOCT) imaging under light and dark conditions. The right eye of each participant was included in the analysis. AL was categorized as short (<22.0 mm), medium (≥22.0 to ≤23.5 mm), or long (>23.5 mm). Anterior segment parameters, including iris dynamic changes, were compared among the three groups with different ALs. RESULTS: Data from 448 patients with PACD were analyzed. We found that 10.9% of included eyes had a long AL with a flatter cornea; larger central anterior chamber depth, angle opening distance, anterior chamber width, anterior chamber area, and volume; and smaller lens thickness and lens vault (LV) (P < 0.05) than those with short AL. No significant difference existed between the three groups in iris thickness, iris cross-sectional area (IA), iris curvature, or pupil diameter (PD) change between light and dark (P > 0.05). The significant associated factors for IA changes were area recess area (ARA) in the dark, LV in the dark, and PD change from light to dark (P < 0.05). CONCLUSIONS: Dynamic and static iris parameters were consistent across patients with PACD with short, medium, or long AL and may contribute to the pathogenesis of angle closure in atypical PACD.

The long and short of it: a comprehensive assessment of axial length estimation in myopic eyes from ocular and demographic variables.

BACKGROUND/OBJECTIVES: Axial length, a key measurement in myopia management, is not accessible in many settings. We aimed to develop and assess machine learning models to estimate the axial length of young myopic eyes. SUBJECTS/METHODS: Linear regression, symbolic regression, gradient boosting and multilayer perceptron models were developed using age, sex, cycloplegic spherical equivalent refraction (SER) and corneal curvature. Training data were from 8135 (28% myopic) children and adolescents from Ireland, Northern Ireland and China. Model performance was tested on an additional 300 myopic individuals using traditional metrics alongside the estimated axial length vs age relationship. Linear regression and receiver operator characteristics (ROC) curves were used for statistical analysis. The contribution of the effective crystalline lens power to error in axial length estimation was calculated to define the latter's physiological limits. RESULTS: Axial length estimation models were applicable across all testing regions (p ≥ 0.96 for training by testing region interaction). The linear regression model performed best based on agreement metrics (mean absolute error [MAE] = 0.31 mm, coefficient of repeatability = 0.79 mm) and a smooth, monotonic estimated axial length vs age relationship. This model was better at identifying high-risk eyes (axial length >98th centile) than SER alone (area under the curve 0.89 vs 0.79, respectively). Without knowing lens power, the calculated limits of axial length estimation were 0.30 mm for MAE and 0.75 mm for coefficient of repeatability. CONCLUSIONS: In myopic eyes, we demonstrated superior axial length estimation with a linear regression model utilising age, sex and refractive metrics and showed its clinical utility as a risk stratification tool.