Prognostic Factors for Axial Length Elongation and Posterior Staphyloma in Adults With High Myopia: A Japanese Observational Study

Distortion-Corrected Posterior Ocular Shape in Myopic Eyes Assessed by Ultrawide OCT Detects Deformations Associated With Vision-Threatening Changes

Purpose

To develop a quantitative tool for assessing the posterior ocular shape using widefield, volumetric optical coherence tomography (OCT) in eyes with myopia.

Methods

This observational, cross-sectional study included 178 eyes from 113 participants. Participants underwent a standardized eye examination, including ocular biometry and a custom ultrawide OCT. True ocular shape was reconstructed by tracing the beam propagation from the system to the posterior eye. Gaussian curvature quantified the localized ocular shape, which was further categorized into five distinct categories. An ocular shape irregularity (OSI) was calculated using principal component analysis. Linear regression with breakpoints analyzed the relationship between ocular shape parameters and axial length (AL).

Results

Increased curvature mean and variance were associated with more severe myopia (P < 0.001). Curvature categories (convex, normal, concave, and highly concave) differed significantly between the groups (all P < 0.001). Their correlations with AL revealed significant breakpoints between 27.1 and 27.2 mm. OSI, as a single metric for quantifying ocular shape distortion, was associated with more severe myopia (P < 0.001), and its correlation with AL revealed a breakpoint at 27.2 mm with a fourfold increase in slope steepness beyond this pivot. Determination of OSI was highly reproducible and could also be obtained with fewer scans.

Conclusions

Eyes exceeding 27.2 mm in length exhibit pronounced shape changes. Our framework can be seamlessly integrated into commercial OCTs for ocular shape deformation detection, which could aid in identifying eyes with pathologic myopia.

Axial elongation in nonpathologic high myopia: Ocular structural changes and glaucoma diagnostic challenges

Axial elongation continues in highly myopic adult eyes, even in the absence of pathologic changes such as posterior staphyloma or chorioretinal atrophy. This ongoing axial elongation leads to structural changes in the macular and peripapillary regions, including chorioretinal thinning, reduced vascular perfusion and optic disc tilting and rotation, among others. These alterations can affect the acquisition and interpretation of optical coherence tomography, optical coherence tomography angiography and fundus photographs, potentially introducing artifacts and diminishing the accuracy of glaucoma diagnosis in highly myopic eyes. In this review, we compared the progression patterns of axial elongation across populations with varying demographic characteristics, genetic and environmental backgrounds and ocular features. We also discussed the implications of axial elongation-induced ocular structural changes for diagnosing glaucoma in nonpathologic high myopia. Finally, we highlighted the prospects for enhancing the diagnostic efficacy of glaucoma in nonpathologic highly myopic populations.

Accuracy of 14 intraocular lens power calculation formulas in extremely long eyes

PURPOSE

To compare the accuracy of 14 formulas in calculating intraocular lens (IOL) power in extremely long eyes with axial length (AL) over 30.0 mm.

METHODS

In this retrospective study, 211 eyes (211 patients) with ALs > 30.0 mm were successfully treated with cataract surgery without complications. Ocular biometric parameters were obtained from IOLMaster 700. Fourteen formulas were evaluated using the optimized A constants: Barrett Universal II (BUII), Kane, Emmetropia Verifying Optical (EVO) 2.0, PEARL-DGS, T2, SRK/T, Holladay 1, Holladay 2, Haigis and Wang-Koch AL adjusted formulas (SRK/Tmodified-W/K, Holladay 1modified-W/K, Holladay 1NP-modified-W/K, Holladay 2modified-W/K, Holladay 2NP-modified-W/K). The mean prediction error (PE) and standard deviation (SD), mean absolute errors (MAE), median absolute errors (MedAE), and the percentage of prediction errors (PEs) within ± 0.25 D, ± 0.50 D, ± 1.00 D were analyzed.

RESULTS

The Kane formula had the smallest MAE (0.43 D) and MedAE (0.34 D). The highest percentage of PE within ± 0.25 D was for EVO 2.0 (37.91%) and the Holladay 1NP-modified-W/K formulas (37.91%). The Kane formula had the highest percentage of PEs in the range of ± 0.50, ± 0.75, ± 1.00, and ± 2.00 D. There was no significant difference in PEs within ± 0.25, ± 0.50 ± 0.75 and ± 1.00 D between BUII, Kane, EVO 2.0 and Wang-Koch AL adjusted formulas (P > .05) by using Cochran's Q test. The Holladay 2modified-W/K formula has the lowest percentage of hyperopic outcomes (29.38%).

CONCLUSIONS

The BUII, Kane, EVO 2.0 and Wang-Koch AL adjusted formulas have comparable accuracy for IOL power calculation in eyes with ALs > 30.0 mm.

Progression Patterns and Risk Factors of Axial Elongation in Young Adults With Nonpathologic High Myopia: Three-Year Large Longitudinal Cohort Follow-Up

PURPOSE

To investigate the progression patterns and risk factors of axial elongation in young adults with nonpathologic high myopia.

DESIGN

Prospective, clinical observational cohort study with 2- to 4-year follow-up.

METHODS

A total of 1043 eyes of 563 participants (3515 medical records) aged 18 to 50 years with nonpathologic high myopia (axial length [AL] ≥ 26 mm; myopic maculopathy < diffuse chorioretinal atrophy; without posterior staphyloma) were included from 1546 participants (6318 medical records). Annual axial elongation was calculated via linear mixed-effect models. The associated risk factors of axial elongation were determined by ordinal logistic regression analysis, with generalized estimate equations for eliminating an interocular correlation bias.

RESULTS

Based on 5359 times of AL measurements, the annual axial elongation of participants (mean [SD] age 31.39 [9.22] years) was 0.03 mm/year (95% confidence interval [CI], 0.03-0.04; P < .001) during a 30.23 (6.06) months' follow-up. Severe (>0.1 mm/year), moderate (0.05-0.09 mm/year), mild (0-0.049 mm/year), and nil (≤0 mm/year) elongation was observed in 122 (11.7%), 211 (20.2%), 417 (40.0%), and 293 (28.1%) eyes. The following risk factors were significantly associated with axial elongation: baseline AL ≥ 28 mm (odds ratio [OR], 4.23; 95% CI, 2.95-6.06; P < .001); age < 40 years (OR, 1.64; 95% CI, 1.18-2.28; P = .003); axial asymmetry (OR, 2.04; 95% CI, 1.26-3.29; P = .003), and women (OR, 1.52; 95% CI, 1.13-2.2.05; P = .006). Using antiglaucoma medications was a protective factor (OR, 0.46; 95% CI, 0.27-0.79; P = .005), which slowed 75% of axial elongation from 0.04 (0.06) to 0.01 (0.06) mm/y (P < .001).

CONCLUSIONS

Axial elongation continued in young adults with nonpathologic myopia. Risk factors included longer baseline AL and axial asymmetry, younger age, and woman. Topical use of antiglaucoma medications may be useful to reduce ongoing axial elongation.

Automated Posterior Scleral Topography Assessment for Enhanced Staphyloma Visualization and Quantification With Improved Maculopathy Correlation

Purpose

To quantitatively characterize the posterior morphology of high myopia eyes with posterior staphyloma.

Methods

Surface points of the eyeball were automatically extracted from magnetic resonance imaging scans using deep learning. Subsequently, the topography of posterior staphylomas was constructed to facilitate accurate visualization and quantification of their location and severity. In the three-dimensional Cartesian coordinate system established with surface points, measurements of distances (D) from each point to the hypothetical pre-elongation eye center within the eyeball and local curvatures (C) at each point on the posterior sclera were computed. Using this data, specific parameters were formulated. The concordance of these parameters with traditional staphyloma classification methods and their association with myopic traction maculopathy (MTM) grades based on the ATN classifications were investigated.

Results

The study included 102 eyes from 52 participants. The measured parameters, particularly the variance of distance (Dvar) and the maximum value of the curvature and distance product (C · Dmax), demonstrated efficacy in differentiating various types of posterior staphyloma and exhibited strong correlations with the grades of MTM.

Conclusions

The automated generation of the posterior scleral topography facilitated visualization and quantification of staphyloma location and severity. Simple geometric parameters can quantify staphyloma shape and correlate well with retinal complications. Future works on expanding these measures to more imaging modalities could improve their clinical use and deepen insights into the link between posterior staphyloma and related retinal diseases.

Translational Relevance

This work has the potential to be translated into clinical practice, allowing for the accurate assessment of staphyloma severity and ultimately improving disease management.

The Mirror Theory: Parallels between Open Angle and Angle Closure Glaucoma

Glaucoma is a widespread ophthalmological disease, with a high impact and frequent visual morbidity. While the physiopathology of the two types of primary glaucoma (open angle and angle closure) has been studied, there seems to be little relationship between the two. In this study, we gather clinical and preclinical data to support the idea that the two primary glaucomas are "mirrored" in terms of morphological parameters and disease physiopathology. In short, primary angle closure glaucoma (PACG) is associated with hyperopia and low axial length, and primary open angle glaucoma (POAG) is associated with myopia and high axial length. Moreover, in PACG and in primary angle closure or primary angle closure suspect cases, while there is extensive iridotrabecular contact, the intraocular pressure (IOP) is still maintained in the lower half of the normal range throughout the evolution of the disease, which suggests a baseline trabecular hyperfiltration in PACG. In the opposite case, myopic eyes with open angles and a higher risk of developing POAG often have a baseline IOP in the upper half of the normal range, suggesting a baseline trabecular hypofiltration. As we explore clinical, genetic and animal model data regarding these opposing aspects, we hypothesize the existence of a mirroring relationship between PACG and POAG. Defining the relationship between the two potentially blinding diseases, with a high prevalence worldwide, may aid in understanding the mechanisms better and refining diagnosis and treatment. Thus, our theory has been named the Mirror Theory of Primary Glaucomas.

Prediction of Axial Length From Macular Optical Coherence Tomography Using Deep Learning Model

Purpose

The purpose of this study was to develop a deep learning model for predicting the axial length (AL) of eyes using optical coherence tomography (OCT) images.

Methods

We retrospectively included patients with AL measurements and OCT images taken within 3 months. We utilized a 5-fold cross-validation with the ResNet-152 architecture, incorporating horizontal OCT images, vertical OCT images, and dual-input images. The mean absolute error (MAE), R-squared (R2), and the percentages of eyes within error ranges of ±1.0, ±2.0, and ±3.0 mm were calculated.

Results

A total of 9064 eyes of 5349 patients (total image number of 18,128) were included. The average AL of the eyes was 24.35 ± 2.03 (range = 20.53-37.07). Utilizing horizontal and vertical OCT images as dual inputs, deep learning models predicted AL with MAE and R2 of 0.592 mm and 0.847 mm, respectively, in the internal test set (1824 eyes of 1070 patients). In the external test set (171 eyes of 123 patients), the deep learning models predicted AL with MAE and R2 of 0.556 mm and 0.663 mm, respectively. Regarding error margins of ±1.0, ±2.0, and ±3.0 mm, the dual-input models showed accuracies of 83.50%, 98.14%, and 99.45%, respectively, in the internal test set, and 85.38%, 99.42%, and 100.00%, respectively, in the external test set.

Conclusions

A deep learning-based model accurately predicts AL from OCT images. The dual-input model showed the best performance, demonstrating the potential of macular OCT images in AL prediction.

Translational Relevance

The study provides new insights into the relationship between retinal and choroidal structures and AL elongation using artificial intelligence models.

Effect of intraocular pressure reduction on progressive high myopia (PHM study): study protocol of a randomised controlled trial

BACKGROUND

In adult patients with high myopia (HM), progressive axial elongation poses a significant risk for the development of subsequent ocular complications that may lead to visual impairment. Effective strategies to reduce or prevent further axial elongation in highly myopic adult patients have not been available so far. Recent studies suggested that medically lowering intraocular pressure (IOP) may reduce axial elongation.

OBJECTIVE

This clinical randomised controlled trial (RCT) aims to evaluate the efficacy of medical IOP reduction in adult patients with progressive HM (PHM).

TRIAL DESIGN

Single-centre, open-label, prospective RCT.

METHODS

This RCT will recruit 152 participants with PHM at the Zhongshan Ophthalmic Center (ZOC). Randomised in a ratio of 1:1, participants will receive IOP-lowering eyedrops (intervention group) or will be followed without treatment (control group) for 12 months. Follow-up visits will be conducted at 1, 6 and 12 months after baseline. Only one eye per eligible participant will be included for analysis. The primary outcome is the change in axial length (AL) within the study period of 12 months. Secondary outcomes include the incidence and progression of visual field (VF) defects, changes in optic disc morphology and incidence and progression of myopic maculopathy. Difference in AL changes between the two groups will be analysed using linear regression analysis. For the secondary outcomes, a multifactor Poisson regression within a generalised linear model will be used to estimate the relative risk of progression in VF defects and myopic maculopathy, and the rate of thinning in retinal nerve fibre layer and ganglion cell-inner plexiform will be assessed through Kaplan-Meier curves and log-rank tests.

ETHICS AND DISSEMINATION

Full ethics approval for this trial has been obtained from the Ethics Committee of ZOC, Sun Yat-sen University, China (ID: 2023KYPJ110). Results of this trial will be disseminated through peer-reviewed journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05850936.

Optic neuropathy in high myopia: Glaucoma or high myopia or both?

Due to the increasing prevalence of high myopia around the world, structural and functional damages to the optic nerve in high myopia has recently attracted much attention. Evidence has shown that high myopia is related to the development of glaucomatous or glaucoma-like optic neuropathy, and that both have many common features. These similarities often pose a diagnostic challenge that will affect the future management of glaucoma suspects in high myopia. In this review, we summarize similarities and differences in optic neuropathy arising from non-pathologic high myopia and glaucoma by considering their respective structural and functional characteristics on fundus photography, optical coherence tomography scanning, and visual field tests. These features may also help to distinguish the underlying mechanisms of the optic neuropathies and to determine management strategies for patients with high myopia and glaucoma.

A wireless battery-free eye modulation patch for high myopia therapy

The proper axial length of the eye is crucial for achieving emmetropia. In this study, we present a wireless battery-free eye modulation patch designed to correct high myopia and prevent relapse. The patch consists of piezoelectric transducers, an electrochemical micro-actuator, a drug microneedle array, μ-LEDs, a flexible circuit, and biocompatible encapsulation. The system can be wirelessly powered and controlled using external ultrasound. The electrochemical micro-actuator plays a key role in precisely shortening the axial length by driving the posterior sclera inward. This ensures accurate scene imaging on the retina for myopia eye. The drug microneedle array delivers riboflavin to the posterior sclera, and μ-LEDs' blue light induces collagen cross-linking, reinforcing sclera strength. In vivo experiments demonstrate that the patch successfully reduces the rabbit eye's axial length by ~1217 μm and increases sclera strength by 387%. The system operates effectively within the body without the need for batteries. Here, we show that the patch offers a promising avenue for clinically treating high myopia.

Axial Elongation Trajectories in Chinese Children and Adults With High Myopia

Importance

Understanding the long-term axial elongation trajectory in high myopia is important to prevent blindness.

Objective

To evaluate axial elongation trajectories and related visual outcomes in children and adults with high myopia.

Design, Setting, and Participants

In this cohort study, participants in the Zhongshan Ophthalmic Centre-Brien Holden Vision Institute high myopia cohort were followed up every other year for 8 years. Participants with axial length measurements at baseline (2011 or 2012) and at least 1 follow-up visit were included. Participants were grouped according to baseline age as children and adolescents (7 to <18 years), young adults (18 to <40 years), and older adults (≥40 to 70 years). Data were analyzed from November 1, 2022, to June 1, 2023.

Exposure

High myopia (spherical power ≤-6.00 diopters).

Main Outcomes and Measures

Longitudinal axial elongation trajectories were identified by cluster analysis. Axial elongation rates were calculated by linear mixed-effects models. A 2-sided P < .05 was defined as statistically significant.

Results

A total of 793 participants (median [range] age, 17.8 [6.8-69.7] years; 418 females [52.7%]) and 1586 eyes were included in the analyses. Mean axial elongation rates were 0.46 mm/y (95% CI, 0.44-0.48 mm/y) for children and adolescents, 0.07 mm/y (95% CI, 0.06-0.09 mm/y) for young adults, and 0.13 mm/y (95% CI, 0.07-0.19 mm/y) for older adults. Cluster analysis identified 3 axial elongation trajectories, with the stable, moderate, and rapid progression trajectories having mean axial elongation rates of 0.02 mm/y (95% CI, 0.01-0.02 mm/y), 0.12 mm/y (95% CI, 0.11-0.13 mm/y), and 0.38 mm/y (95% CI, 0.35-0.42 mm/y), respectively. At 8 years of follow-up, compared with the stable progression trajectory, the rapid progression trajectory was associated with a 6.92 times higher risk of developing pathological myopic macular degeneration (defined as diffuse or patchy chorioretinal atrophy or macular atrophy; odds ratio, 6.92 [95% CI, 1.07-44.60]; P = .04), and it was associated with a 0.032 logMAR decrease in best-corrected visual acuity (β = 0.032 [95% CI, 0.001-0.063]; P = .04).

Conclusions and Relevance

The findings of this 8-year follow-up study suggest that axial length in high myopia continues to increase from childhood to late adulthood following 3 distinct trajectories. At 8 years of follow-up, the rapid progression trajectory was associated with a higher risk of developing pathological myopic macular degeneration and poorer best-corrected visual acuity compared with the stable progression trajectory. These distinct axial elongation trajectories could prove valuable for early identification and intervention for high-risk individuals.

Cutoff values of axial length/corneal radius ratio for determining myopia vary with age among 3-18 years old children and adolescents

PURPOSE

To investigate the effectiveness and cutoffs of axial length/corneal radius (AL/CR) ratio for myopia detection in children by age.

METHODS

Totally, 21 kindergartens and schools were enrolled. Non-cycloplegic autorefraction (NCAR), axial length (AL), horizontal and vertical meridian of corneal radius (CR1, CR2), and cycloplegic autorefraction were measured. Receiver operating characteristic (ROC) curve was used to obtain the effectiveness and cutoff for myopia detection.

RESULTS

Finally, 7803 participants aged 3-18 years with mean AL/CR ratio of 2.99 ± 0.16 were included. Area under the ROC curve (AUC) of AL/CR ratio for myopia detection (0.958 for AL/CR1, 0.956 for AL/CR2, 0.961 for AL/CR) was significantly larger than that of AL (0.919, all P < 0.001), while AUCs of the three were similar with different cutoffs (> 2.98, > 3.05, and > 3.02). When divided by age, the ROC curves of AL/CR ratio in 3- to 5-year-olds showed no significance or low accuracy (AUCs ≤ 0.823) in both genders. In ≥ 6-year-olds, the accuracies were promising (AUCs ≥ 0.883, all P < 0.001), the cutoffs basically increased with age (from > 2.93 in 6-year-olds to > 3.07 in 18-year-olds among girls, and from > 2.96 in 6-year-olds to > 3.07 in 18-year-olds among boys). In addition, boys presented slightly larger cutoffs than girls in all ages except for 16 and 18 years old. For children aged 3-5 years, AL/CR ratio or AL combined with NCAR increased AUC to > 0.900.

CONCLUSION

AL/CR ratio provided the best prediction of myopia with age-dependent cutoff values for all but preschool children, and the cutoffs of boys were slightly larger than those of girls. For preschool children, AL/CR ratio or AL combined with NCAR is recommended to achieve satisfactory accuracy. AL/CR ratio calculated by two meridians showed similar predictive power but with different cutoffs.

Influence of posterior staphyloma in myopic maculopathy and visual prognosis

BACKGROUND/OBJECTIVES

Posterior staphyloma is a hallmark of high myopia and its presence associates to greater degrees of myopic maculopathy. Nonetheless, its development, repercussion on visual function and relationship with maculopathy components, is still unclear. The objective was to analyze the impact of posterior staphyloma on the incidence and severity of myopic maculopathy and its repercussion on visual prognosis.

SUBJECTS/METHODS

Cross-sectional study conducted on 473 consecutive eyes of 259 highly myopic patients examined at Puerta de Hierro-Majadahonda University Hospital (Madrid, Spain). All patients underwent complete ophthalmologic examination including best corrected visual acuity (BCVA), axial length (AL), myopic maculopathy classification according to ATN system (atrophic/traction/neovascularization), determined the presence of posterior staphyloma, pathologic myopia (PM) and severe PM. Multimodal imaging were performed including fundus photography, optical coherence tomography (OCT), OCT-angiography, fundus autofluorescence and/ or fluorescein angiography.

RESULTS

Out of the total, 70.65% were female patients (n = 173/259), mean BCVA was 0.41 ± 0.54 logMAR units and mean AL was 29.3 ± 2.6 mm (26-37.6). Posterior staphyloma was present in 69.4% of eyes. Eyes with posterior staphyloma compared to non-staphyloma were older (p < 0.05), had greater AL (p < 0.01), worse BCVA (p < 0.01) and higher stage in ATN components (p < 0.01). Moreover, compound subgroup showed worse BCVA (p < 0.01) and greater stage in each of the ATN components (p < 0.01). Staphylomas with macular involvement presented worse BCVA (p < 0.01), higher AL (p < 0.01), and greater ATN (p < 0.05). The risk of posterior staphyloma presence in eyes with PM and severe PM eyes was 89.8% and 96.7%, respectively. Posterior staphyloma was the best predictor for BCVA in myopic patients (p < 0.01).

CONCLUSIONS

Posterior staphyloma's presence determines high risk of myopic maculopathy and therefore worse visual prognosis, especially those with macular involvement. Posterior staphyloma represented the best predictor for BCVA in highly myopic patients.

Incidence and its risk factors of high myopia in Chinese rural adults: A population-based six-year cohort study

BACKGROUND

To investigate the incidence rate of high myopia and its risk factors in adults.

METHODS

This was a population-based cohort study, 4582 adults aged ≥ 30 years from rural area of China were included. The follow-up duration was six years. Objective refraction (sphere, cylinder, and axis) was measured using an autorefractor. Multivariable Logistic regression was used to explore risk factors of high myopia, odds ratio (OR) with 95% confidence interval (CI) were reported.

RESULTS

During the six-year follow-up, 25 participants developed high myopia. The incidence rate was 0.55% (95%CI: 0.44% to 0.66%), and were 0.54% (11/2035) in males and 0.55% (14/2547) in females. The age-gender standardized annual incidence rate was 0.11%. The median changes in spherical equivalent (SE) of all participants was 0.25D (IQR: -0.125 to 0.625). For the baseline myopic adults and non-myopic adults, the median changes in SE were 0.125D (IQR: -0.375 to 0.5), and 0.25D (IQR: -0.125 to 0.625). The difference was significant (p < 0.001). Of the two subgroups, 1.52% (21/1383) and 0.13% (4/3199) developed high myopia during six years. The risk of developing high myopia in baseline myopic adults was 11.7 times higher than that of the baseline non-myopic adults (p < 0.001). Age (OR = 1.061, 95%CI: 1.022 to 1.103, p = 0.002), and baseline myopia (OR = 1.007, 95%CI: 1.001 to 1.012, p < 0.001) were risk factors for high myopia.

CONCLUSION

The age-gender standardized annual incidence rate of high myopia in Chinese rural adults is 0.11%. More than 30% of adults still have myopia progression. Myopia control is of great significance for high myopia prevention.

Effects of dopamine D2 receptor antagonists on retinal pigment epithelial/choroid complex metabolism in form-deprived myopic guinea pigs

The retinal pigment epithelial (RPE)/choroid complex regulates myopia development, but the precise pathogenesis of myopia remains unclear. We aimed to investigate the changes in RPE/choroid complex metabolism in a form deprivation myopia model after dopamine D2 receptor (D2R) modulation. Guinea pigs were randomly divided into normal (NC), form deprivation myopia (FDM), and FDM treated with dopamine D2R antagonist groups. Differential metabolites were screened using SIMCA-P software and MetaboAnalyst metabolomics analysis tool. Functions of differential metabolites were analyzed using KEGG enrichment pathways. Relative to the NC group, 38 differential metabolites were identified, comprising 29 increased metabolites (including nicotinic acid, cytosine, and glutamate) and 9 decreased metabolites, of which proline exhibited the largest decrease. Pathway analysis revealed regulation of arginine/proline and aspartate/glutamate metabolism. Intravitreal D2R antagonist injection increased proline concentrations and activated arginine/proline and purine metabolism pathways. In sum, D2R antagonists alleviated the myopia trend of refractive biological parameters in form deprivation myopic guinea pigs, suggesting the involvement of dopamine D2R signaling in myopia pathogenesis. The RPE/choroid may provide glutamate to the retina by activating proline metabolism via metabolic coupling with the retina. Dopamine D2R antagonism may modulate proline/arginine metabolic pathways in the RPE/choroid and regulate metabolism, information presentation, and myopia.

What Should We Pay More Attention to Marfan Syndrome Expecting Ectopia Lentis: Incidence and Risk Factors of Retinal Manifestations

(1) Background: This paper investigates the incidence and risk factors of retinal manifestations in patients with Marfan syndrome (MFS) in a Chinese cohort. (2) Methods: This is a population-based cross-sectional study. In total, 344 eyes (172 MFS participants) were enrolled, each of whom underwent a detailed ocular examination. B-scan ultrasonography, ultra-wide-angle fundus images and optical coherence tomography images were conducted to assess posterior staphyloma, types of retinal damages and maculopathy. (3) Results: MFS patients have a high proportion (32.5%) of maculopathy, among which atrophy is the most common type (27.6%). Compared with participants without maculopathy, participants with maculopathy had a longer axial length (AL), higher incidence of posterior staphyloma, macular split and retinal detachment (RD) (p < 0.001, p < 0.001, p < 0.001 and p = 0.001). Moreover, the stage of RD has a significant correlation with longer AL and shallower anterior chamber depth (ACD) (p = 0.001 and p = 0.034, respectively). (4) Conclusions: A higher incidence and earlier onset of fundus lesions were found in MFS patients. Yearly systematic examination is recommended for MFS children with fundus manifestation until the cardiovascular and skeletal development is complete.

Hospital-Based Study of Risk Factors Associated with Development of Myopic Macular Neovascularization in Highly Myopic Eyes

INTRODUCTION

Myopic macular neovascularization (MNV) is the most common cause of a reduction of central vision in eyes with pathologic myopia, and it can progress to macular atrophy in the long term. The aim of this study was to determine the risk factors associated with the development of MNVs.

METHODS

There were 17,198 follow-up records from 5,409 eyes of 2,784 highly myopic patients that were reviewed. The general information and ophthalmic information in the records were studied. The significance of the correlations of factors associated with the development and predicting the development of myopic MNV were determined.

RESULTS

Being a woman (odds ratio [OR] = 0.727, p < 0.001), having a longer axial length (OR = 0.948, p < 0.001), having a poorer baseline best-correct visual acuity (BCVA, OR = 2.098, p < 0.001), having severe myopic maculopathy (overall: p < 0.001), prior myopic MNV in the fellow eye (OR = 4.105, p < 0.001), presence of patchy atrophy (overall p < 0.001), lacquer cracks (OR = 1.718, p < 0.001), prior foveal retinal detachment (RD, OR = 3.269, p < 0.001), prior macular hole (MH, OR = 0.641, p < 0.001), prior macular retinoschisis (OR = 1.533, p < 0.001), and prior macular edema (OR = 1.508, p < 0.001) were significantly correlated with the development of myopic MNV. Eyes with MNV and patchy atrophy would require an intensive follow-up examination for myopic patients as the fellow eye would have a risk of >70% for the development of myopic MNV in 3 years and nearly 80% in 5 years.

CONCLUSIONS

Clinicians need to pay special attention to eyes with severe grades of myopic maculopathy, prior myopic MNV in the fellow eye, presence of patchy atrophy, and prior foveal retinal detachment to determine the onset of myopic MNV.

A Review of Intraocular Pressure (IOP) and Axial Myopia

The pathogenesis of myopia is driven by genetic and environmental risk factors. Accommodation not only alters the curvature and shape of the lens but also involves contraction of the ciliary and extraocular muscles, which influences intraocular pressure (IOP). Scleral matrix remodeling has been shown to contribute to the biomechanical susceptibility of the sclera to accommodation-induced IOP fluctuations, resulting in reduced scleral thickness, axial length (AL) elongation, and axial myopia. The rise in IOP can increase the burden of scleral stretching and cause axial lengthening. Although the accommodation and IOP hypotheses were proposed long ago, they have not been validated. This review provides a brief and updated overview on studies investigating the potential role of accommodation and IOP in myopia progression.

Association between axial length elongation and spherical equivalent progression in Chinese children and adolescents

BACKGROUND

It is generally believed that a 1-mm axial length (AL) elongation of the eye corresponds to a -3.00 D spherical equivalent (SE) progression, but this is disputed.

PURPOSE

To investigate the association between AL elongation and SE progression among children and adolescents.

METHODS

A prospective cohort study of 710 children and adolescents aged 6-16 years was included. Ophthalmic examinations, including cycloplegic SE, AL and corneal curvature, were performed at baseline and 1-year follow-up. The ratio of SE change (ΔSE) to AL change (ΔAL) (ΔSE/ΔAL) was calculated, and its association with age and refractive status was explored using a general linear model.

RESULTS

Among all participants, 396 (55.77%) were male, with 265 (37.32%) myopes at baseline. The average 1-year ΔSE and ΔAL were 0.61 ± 0.40 D and 0.33 ± 0.22 mm, respectively. Both ΔSE and ΔAL gradually decreased with age (p < 0.001). In the general linear model analyses, age and refractive status were independently associated with ΔSE/ΔAL after adjustment for covariates (age: β ̂ $$ \hat{\beta} $$  = 0.04, p < 0.05; myopia vs nonmyopia: β ̂ $$ \hat{\beta} $$  = 0.28, p < 0.05). Based on the developed formula ΔSE/ΔAL = 1.74 + 0.05*age (for myopes), mean ΔSE/ΔAL in myopes increased from 2.06 D/mm in the 6-year-olds to 2.59 D/mm in the 16-year-olds. In nonmyopes, ΔSE/ΔAL = 1.33 + 0.05*age, and the ratio increased from 1.65 D/mm in the 6-year-olds to 2.18 D/mm in the 16-year-olds.

CONCLUSIONS

The ratio of ΔSE/ΔAL varied with age and refractive status in children and adolescents. The age-specific ΔSE/ΔAL could be used to estimate SE progression through the actual AL change.

Investigation of Macular Structural and Microcirculatory Characteristics of Posterior Staphyloma in High Myopic Eyes by Swept Source Optical Coherence Tomography Angiography

Purpose: To investigate the characteristics of macular structures and microcirculation of posterior staphyloma (PS) and explored factors related to PS in eyes with high myopia.

Methods: There were 114 eyes of 82 patients in this study. Using 1:1 matching of the axial length of myopic eyes, patients were divided into no PS (NPS) and PS groups. Comprehensive ophthalmic examinations were performed on all patients. Structural parameters were acquired using swept source optical coherence tomography (SS-OCT). OCT angiography (OCTA) was used to measure the microcirculation parameters. Generalized estimated equation and linear correlation analysis were used for the statistical analysis.

Results: Patients with PS had a thinner retinal thickness (RT) and choroid thickness (CT) (all p < 0.05) in the measurement areas and a significantly lower subfoveal scleral thickness (SFST) (p < 0.001) than those without PS. Retinal deep vascular complex density (DVD) (all p < 0.05) and choriocapillaris perfusion area (CCPA) (all p < 0.001) were significantly lower in the measurement areas of the PS group than in those of the NPS group. There was no significant difference in the retinal superficial vascular density between the two groups. Generalized estimating equation indicated that SFST (B = 0.079, p = 0.001), parafoveal RT (B = −0.162, p = 0.041), foveal CT (B = 0.292, p = 0.013), parafoveal CT (B = −0.157, p = 0.023), foveal CCPA (B = 0.691, p = 0.003) and parafoveal CCPA (B = −0.026, p = 0.004) were significantly correlated with PS. Age (r = −0.323, p = 0.001), spherical equivalent refraction (SER) (r = 0.289, p = 0.004), subfoveal CT (r = 0.398, p < 0.001), foveal DVD (r = 0.346, p < 0.001), foveal CT (r = 0.429, p < 0.001), and foveal CCPA (r = 0.387, p < 0.001) were strongly correlated with SFST.

Conclusions: The macular structures and microcirculation in the PS group were different from those in the NPS group. SFST, CT, and CCPA were significantly correlated with PS. Lower SFST in PS was correlated with abnormalities of CT and microcirculation.

Higher-order aberrations and their association with axial elongation in highly myopic children and adolescents

BACKGROUND

Vision-dependent mechanisms play a role in myopia progression in childhood. Thus, we investigated the distribution of ocular and corneal higher-order aberrations (HOAs) in highly myopic Chinese children and adolescents and the relationship between HOA components and 1-year axial eye growth.

METHODS

Baseline cycloplegic ocular and corneal HOAs, axial length (AL), spherical equivalent (SE), astigmatism and interpupillary distance (IPD) were determined for the right eyes of 458 highly myopic (SE ≤-5.0D) subjects. HOAs were compared among baseline age groups (≤12 years, 13-15 years and 16-18 years). Ninety-nine subjects completed the 1-year follow-up. Linear mixed model analyses were applied to determine the association between HOA components, other known confounding variables (age, gender, SE, astigmatism and IPD) and axial growth. A comparison with data from an early study of moderate myopia were conducted.

RESULTS

Almost all ocular HOAs and few corneal HOAs exhibited significant differences between different age groups (all p<0.05). After 1 year, only ocular HOA components was significantly negative associated with a longer AL, including secondary horizontal comatic aberration (p=0.019), primary spherical aberration (p<0.001) and spherical HOA (p=0.026). Comparing with the moderate myopia data, the association of comatic aberration with AL growth was only found in high myopia.

CONCLUSION

In highly myopic children and adolescents, lower levels of annual ocular secondary horizontal comatic aberration changes, besides spherical aberrations, were associated with axial elongation. This suggests that ocular HOA plays a potential role in refractive development in high myopia.

Four-year follow up of macular intrachoroidal cavitation and chorioretinal atrophy: A case report

RATIONALE

Macular intrachoroidal cavitation (ICC) is characterized by presence of a hyporeflective space beneath the unaltered retinal pigment epithelium (RPE) and is noted around the region of focal chorioretinal atrophy in eyes with pathologic myopia. The findings suggest that the patchy chorioretinal atrophy (PCA) progresses to ICC with time. However, there have been no reports describing long-term observational studies using OCT. We collected a case of PCA progression to macular ICC using OCT during a 4-year follow-up.

PATIENT CONCERNS

A 65-year-old woman presented with metamorphopsia and blurred vision in her left eye. Her best-corrected visual acuity (BCVA) was 20/20 and spherical equivalent refraction was -14.0 diopters in the left eye. Fundus examination revealed a white, well-defined PCA at the superonasal to the fovea which showed hypofluorescence determined by autofluorescence in the left eye. Sclera curved posteriorly at the superonasal to the fovea and the choroid was thickened at the area and ellipsoid zone (EZ) was disrupted in the area in OCT images. Additionally, another OCT images through the PCA showed a disappearance of the RPE-Bruch's membrane complex and a connection of blood vessels running from the sclera to the choroid.

DIAGNOSES

PCA with macular ICC.

INTERVENTIONS

Observation.

OUTCOMES

During 4-year follow up, the white patchy lesion and the hypofluorescence region gradually expanded. BCVA decreased with the expansion of the lesion and was 20/100 at the final visit. OCT through the fovea showed that the disorganized EZ expanded toward the ICC and the sensory retina of the fovea became thinner. Moreover, RPE-Bruch's membrane complex was not observed 3 years after the initial visit. During the follow-up period, the sensory retina was prominently displaced posteriorly to the ICC, though no obvious change was observed in the structure of the sclera.

LESSONS

In cases of PCA with macular ICC, the outer retina and RPE may initially atrophy, showing as an expansion of PCA, because the attachment between the inner retina and sclera may be weakened. This may result in the displacement of the retinal tissue into the space of macular ICC.

Lowering Intraocular Pressure: A Potential Approach for Controlling High Myopia Progression

High myopia is among the most common causes of vision impairment, and it is mainly characterized by abnormal elongation of the axial length, leading to pathologic changes in the ocular structures. Owing to the close relationship between high myopia and glaucoma, the association between intraocular pressure (IOP) and high myopia progression has garnered attention. However, whether lowering IOP can retard the progression of high myopia is unclear. On reviewing previous studies, we suggest that lowering IOP plays a role in progressive axial length elongation in high myopia, particularly in pathologic myopia, wherein the sclera is more remodeled. Based on the responses of the ocular layers, we further proposed the potential mechanisms. For the sclera, lowering the IOP could inhibit the activation of scleral fibroblasts and then reduce scleral remodeling, and a decrease in the scleral distending force would retard the ocular expansion like a balloon. For the choroid, lowering IOP results in an increase in choroidal blood perfusion, thereby reducing scleral hypoxia and slowing down scleral remodeling. The final effect of these pathways is slowing axial elongation and the development of scleral staphyloma. Further animal and clinical studies regarding high myopia with varied degree of IOP and the changes of choroid and sclera during IOP fluctuation in high myopia are needed to verify the role of IOP in the pathogenesis and progression of high myopia. It is hoped that this may lead to the development of a prospective treatment option to prevent and control high myopia progression.

Differences in Retinal and Choroidal Vasculature and Perfusion Related to Axial Length in Pediatric Anisomyopes

Purpose

The purpose of this study was to evaluate the interocular differences in choroidal vasculature, choriocapillaris perfusion, and retinal microvascular network, and to explore their associations with interocular asymmetry in axial lengths (ALs) in children with anisomyopia.

Methods

Refractive error, AL, and other biometric parameters were measured in 70 children with anisomyopia. Using optical coherence tomography (OCT) and OCT-angiography, we measured the submacular choroidal thickness (ChT), total choroidal area (TCA), luminal area (LA), stromal area (SA), choroidal vascularity index (CVI), choriocapillaris flow deficit (CcFD), retinal vessel density (VD), and foveal avascular zone (FAZ) area.

Results

The mean interocular differences in spherical equivalent refraction and AL were −2.26 ± 0.94 diopters and 0.95 ± 0.46 mm, respectively. Submacular ChT, TCA, LA, SA, and CVI were all significantly lower in the more myopic (longer AL) eyes than in the less myopic (shorter AL) fellow eyes. In eyes with longer ALs, both the CcFD and FAZ areas were significantly greater, whereas the superficial and deep retinal VDs were significantly less. After adjusting for corneal power and intraocular pressure, interocular differences in LA (β = −0.774), SA (β = −0.991), and CcFD (β = 0.040) were significantly associated with interocular asymmetry in AL (all P < 0.05).

Conclusions

In pediatric anisomyopes, eyes with longer ALs tended to have lower choroidal vascularity and choriocapillaris perfusion than the contralateral eyes with shorter ALs. Longitudinal investigations would be useful follow-ups to test for a causal role of choroidal circulation in human myopia.

IMI 2021 Reports and Digest - Reflections on the Implications for Clinical Practice

The International Myopia Institute's (IMI) mission is to advance research, education, and management of myopia to decrease future vision impairment and blindness associated with increasing myopia. Its approach is to bring together scientists, clinicians, policymakers, government members, and educators into the field of myopia to stimulate collaboration and sharing of knowledge. The latest reports are on pathologic myopia, the impact of myopia, risk factors for myopia, accommodation and binocular vision in myopia development and progression, and the prevention of myopia and its progression. Together with the digest updating the 2019 International Myopia Institute white papers using the research published in the last 18 months, these evidence-based consensus white papers help to clarify the imperative for myopia control and the role of environmental modification initiatives, informing an evidence-based clinical approach. This guidance includes who to treat and when to start or stop treatment, and the advantages and limitations of different management approaches.