The Association of Refractive Error with Glaucoma in a Multiethnic Population

Association between ocular diseases and screen time and sedentary time derived from job-exposure matrices

After developing job-exposure matrices (JEMs) for screen and sedentary time, we aimed to assess the associations between the JEM-derived exposures and various ocular diseases. We collected data from patients hospitalized from 2005 to 2021. JEMs were developed from 41,718 patients with occupational information and screen and sedentary times. The adjusted means of screen and sedentary time were calculated for 143 occupational groups and categorized into three classes based on the tertiles. The associations between ocular diseases and these JEM-derived exposures were examined using multivariable conditional logistic regression for 727,589 patients. The odds ratios of the class with highest screen time were 1.05 (95% confidence interval, 1.01-1.09) for cataract, 1.24 (1.06-1.45) for primary open-angle glaucoma (POAG), 1.26 (1.06-1.49) for rhegmatogenous retinal detachment (RRD), 1.49 (1.26-1.76) for ptosis, and 0.39 (0.27-0.57) for pterygium. The odds ratios of the class with highest sedentary time were 1.05 (1.01-1.09) for cataract, 1.24 (1.05-1.46) for RRD, 1.68 (1.42-1.99) for ptosis, and 0.60 (0.42-0.84) for pterygium. Both screen and sedentary time were positively associated with cataract, RRD and ptosis. Interestingly, POAG had a positive association with only screen time. Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary."I have confirmed that the content is correct. No amendments are necessary.Please check article title if captured correctly."?>"I have confirmed that the content is correct. No amendments are necessary.

The lack of causal link between myopia and intraocular pressure: Insights from cross-sectional analysis and Mendelian randomization study

OBJECTIVE

This study aimed to explore the potential causal relationship between intraocular pressure (IOP) and myopia.

METHODS

The study included 3,459 patients who underwent corneal refractive surgery at our institution between 2021 and 2023. Preoperative data on IOP, spherical equivalent (SE), axial length (AL), and corneal thickness (CCT) were collected. The association between IOP and myopia was investigated through rank correlation analysis, and causal inference was examined using Mendelian randomization (MR) methods, including MR-Egger, weighted median, mode-based estimation, simple mode, and inverse variance weighted (IVW) approaches. Utilizing summary statistics from genome-wide association studies (GWAS), IOP was considered as the exposure, with myopia as the outcome variable. IVW method was employed for the primary analysis, supplemented by sensitivity analyses.

RESULTS

Cross-sectional analysis revealed a non-significant association between corrected IOP (cIOP) and myopia (r = -0.019, P = 0.12). MR analysis indicated a non-significant genetic causal relationship between cIOP and myopia under the IVW method (OR = 1.001; 95 % CI [0.999-1.003], P = 0.22), a finding corroborated in replication samples (OR = 0.98; 95 % CI [0.96-1.00], P = 0.099).

CONCLUSION

This study did not find a direct causal link between IOP and the development of myopia. These findings challenge the traditional role attributed to IOP in the progression of myopia and highlight the complex, multifactorial process of myopia development. This provides a new perspective on understanding the intricate mechanisms behind myopia progression.

Distribution and Determinants of Anterior Chamber Angle and Anterior Chamber Volume in Young Chinese Adults

PURPOSE

Current study aimed to understand the distribution and determinants of anterior chamber angle (ACA) and anterior chamber volume (ACV) in Chinese young adults, which can help fill current data gaps and aid in early detection and intervention for high-risk population of primary angle closure glaucoma.

METHODS

This cross-sectional study utilized data from 2014 participants who completed questionnaire and eye examination in September 2021. ACV and ACA were measured using a Pentacam tomographer. Spherical equivalent (SE) was evaluated by autorefractor without cycloplegia. Central corneal thickness (CCT) and biomechanically corrected intraocular pressure (bIOP) were evaluated using Corvis-ST. Axial length (AL), corneal radius (CR), anterior chamber depth (ACD), and white to white were assessed using the IOL Master.

RESULTS

A total of 1635 students were included in the analysis. The mean ACV and AVA were 194.74 ± 32.30 μL and 38.81 ± 4.84°, respectively. Males have a larger ACV and wider ACA than females. ACV was positively correlated with ACA (r = 0.24, p < 0.001), and the correlation was stronger for non-myopic students than for myopic students. Multivariable linear regression model showed that AL (β = 2.41), CR (β = -4.12), CCT (β = -0.11), ACD (β = 97.93), and bIOP (β = 0.40) were associated with ACV, and CCT (β = -0.01), CR (β = 0.38), and ACD (β = 7.41) were associated with ACA (all p < 0.05). Random forest model indicated that ACD was the most critical predictor of both ACV and ACA.

CONCLUSIONS

This study reported the distribution and determinants of ACA and ACV. Deeper ACD was associated with larger ACV and wider ACA.

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.

Intraocular pressure reduction and progression of highly myopic glaucoma: a 12-year follow-up cohort study

AIMS

To investigate any association between intraocular pressure (IOP) reduction amount and open-angle glaucoma (OAG) progression in highly myopic eyes and to determine the associated risk factors.

METHODS

One hundred and thirty-one (131) eyes of 131 patients with highly myopic OAG, all of whom had received topical medications and been followed for 5 years or longer, were enrolled. Based on the IOP reduction percentage, patients were categorised into tertile groups, and subsequently, the upper-tertile and lower-tertile groups were compared for the cumulative probability of glaucoma progression. Kaplan-Meier survival analysis and log-rank testing were applied in the comparison, and multivariate analysis with Cox's proportional hazard model, additionally, was performed to identify progression risk factors.

RESULTS

Throughout the average 11.6±4.4 year follow-up on the 131 eyes (mean age, 41.2 years at initial visit; baseline IOP, 16.4 mm Hg), 72 eyes (55.0%) showed glaucoma progression. The upper-tertile group (IOP reduction percentage>23.7%) showed a high cumulative probability of non-progression relative to the lower-tertile group (IOP reduction percentage<11.0%; p=0.034), according to the Kaplan-Meier analysis. Presence of disc haemorrhage (DH; HR=2.189; p=0.032) was determined by the multivariate Cox's proportional hazard model to be significantly associated with glaucoma progression. For progressors, the average rate of retinal nerve fibre layer thickness thinning was -0.88±0.74 µm/year, while the MD change was -0.42±0.36 dB/year.

CONCLUSIONS

Glaucoma progression is associated with amount of IOP reduction by topical medications in highly myopic eyes, and DH occurrence is a glaucoma progression risk factor.

Central visual field in glaucoma: An updated review

Evaluation of central vision in glaucoma is important due to its impact on patients' quality of life and activities of daily living such as reading, driving, and walking. The 10-2 visual field (VF) assessment remains a mainstay in the functional analysis of central vision in glaucoma diagnosis and progression. However, it may be underutilized in clinical practice. Monitoring of disease progression especially in advanced cases, glaucoma evaluation in certain ocular disorders such as high myopia, disc hemorrhage, low corneal hysteresis, and certain optic disc phenotypes, as well as earlier detection of central VF damage, are certain conditions where additional monitoring with the 10-2 pattern may provide complementary clinical information to the commonly utilized 24-2 pattern. In addition, the development of artificial intelligence techniques may assist clinicians to most effectively allocate limited resources by identifying more risk factors to central VF damage. In this study, we aimed to determine specific patient characteristics that make central VF damage more likely and to assess the benefit of incorporating the 10-2 VF in various clinical settings.

Bridging gaps in ophthalmology residency programs: the link between practice, training and confidence in ocular examination and gonioscopy for diagnosing glaucoma, a blinding disease

BACKGROUND

To evaluate real-world utilization of gonioscopy for diagnosing glaucoma among ophthalmologists with diverse subspecialties, and understand current perceptions of teaching, training, and confidence in gonioscopy.

METHODS

A nationwide anonymous online survey was conducted among practicing ophthalmologists, querying about demographics, professional experience, practice of routine ocular examination for glaucoma and perceptions of confidence in performing them.

RESULTS

136 ophthalmologists participated in the survey, with various levels of experience from residency to over twenty years of ophthalmology practice. Glaucoma specialists comprised 23 (16.9%) of the participants. Of the non-glaucoma-specialist respondents, only 33 (29.2%) expressed being highly confident in interpreting gonioscopic findings, which correlated significantly with their self-reported inadequate level of training in gonioscopy during residency (p < 0.001) and even more so with their low frequency of implementing gonioscopy in routine examinations (p < 0.001). The commonly cited reasons for the low practice of gonioscopy were insufficient time allotted to examinations and lack of experience, knowledge or equipment.

CONCLUSIONS

Gonioscopy is fundamental to the detection of glaucoma. This study reveals underutilization of gonioscopy in the practice of ophthalmology and its association with lower training opportunities, calling for expedited changes in the residency's curriculum, alongside measures to promote its use in clinical practice.

Retinal vein occlusion in patients with primary angle closure: a prospective case-control study

OBJECTIVE

To compare the prevalence of angle closure in eyes with retinal vein occlusion (RVO) with control eyes and assess the possible association between angle-closure and RVO.

PATIENTS AND METHODS

This prospective, blinded case-control study included patients with a history of RVO (cases) and control individuals matched for age and refractive error. Clinical characteristics and angle-based structures derived from anterior-segment optical coherence tomography (AS-OCT) were analyzed.

RESULTS

Eighty-eight patients (44 per group) were included. The average age of the RVO and control groups was 59.8 ± 11.6 years and 60.8 ± 9.0 years, respectively (p = 0.667). There were no significant differences in terms of clinical characteristics between the 2 groups, including intraocular pressure (p = 0.837) and Shaffer gonioscopy grading (p = 0.620). None of the AS-OCT-derived angle characteristics were significantly different between the 2 groups. The number of angle-closure diagnoses between the RVO group (1 primary angle closure and 7 primary angle-closure suspects) and the control group (6 primary angle-closure suspects) did not differ significantly (p = 0.560). Anterior-chamber depth (ACD) was shallower in RVO eyes (2.72 ± 0.31 mm) than in the contralateral non-RVO eyes (2.76 ± 0.31 mm; p = 0.014).

CONCLUSIONS

This prospective, blinded, matched case-control study did not evidence any significant differences in clinical and AS-OCT-derived structural measures between RVO and control eyes. However, RVO eyes, compared with their contralateral non-RVO eyes, had a slightly shallower ACD. These findings collectively suggest that an association between primary angle-closure mechanisms and RVO is unlikely. However, the shallower ACD in RVO eyes could potentially put them at higher risk for intermittent or permanent pupillary block.

Long-term Treatment Outcomes for Malignant Glaucoma

PURPOSE

To report the contributing factors to the successful long-term treatment outcomes of a large series of patients with malignant glaucoma (MG).

DESIGN

Retrospective, interventional, consecutive case series.

PARTICIPANTS

This study used data collected from 1997 to 2022 from the Glaucoma Division of the Stein Eye Institute, University of California, Los Angeles (UCLA). All patients with MG who underwent treatment at UCLA were enrolled.

METHODS

The following demographic and clinical data were collected and analyzed for their relevance to successful treatment: age, gender, ethnicity, glaucoma family history, visual acuity (VA), intraocular pressure (IOP), lens status, prior glaucoma diagnosis, prior ocular surgery, prior use of antiglaucoma agents, ultrasonic axial length, qualitative anterior chamber (AC) depth, and treatment methods and outcomes.

MAIN OUTCOME MEASURES

Anatomical success was defined as restoration of normal AC depth, indicating relief of the MG episode. Complete success was defined as anatomical success and the reduction of IOP to < 21 mmHg without further surgery, with or without medications.

RESULTS

A total of 74 eyes of 73 patients were identified with a diagnosis of MG. The median (interquartile range) age of the patients at the time of MG presentation was 70 years (19.5) and 49 (75.4%) patients were female. The most common prior diagnosis before MG was primary angle closure glaucoma (PACG) (34 eyes, 51.5%). The initiating event for 30 eyes (45.5%) was glaucoma surgery and for 21 eyes (31.8%) was cataract surgery. Most eyes were pseudophakic (57, 86.4%). Fifty-six eyes underwent medical treatment; MG resolved in 2 eyes with medical treatment alone. Nine eyes (7 eyes = treatment naïve; 2 eyes = failed medical treatment) underwent laser treatment and MG resolved in 5 eyes. Among the 55 eyes which had surgical treatment, 52 eyes failed medical treatment and 3 eyes were treatment naïve. The anatomical success rate with surgical treatment was 96.4% and the most commonly performed surgical procedure was combined pars plana antero-central vitrectomy, hyaloido-zonulectomy, and iridectomy.

CONCLUSIONS

Female gender, PACG, and glaucoma surgery were predisposing factors for the development of MG. Medical treatment alone for MG was inadequate in the vast majority of cases. A surgical technique consisting of combined pars plana antero-central vitrectomy, hyaloido-zonulectomy and iridectomy consistently produced high long-term success.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

PRESERFLO MicroShunt in Severe Myopia: A Case Report and Review of the Literature

The PRESERFLO™ MicroShunt (MP; Santen Inc., Osaka, Japan) is a minimally invasive bleb surgery (MIBS) manufactured to treat primary open-angle glaucoma (POAG), with lower postoperative adverse effects than with conventional filtering surgeries. We describe here the case study of a 58-year-old woman who presented with bilateral severe myopia with bilateral advanced POAG and unreached target pressure under quadritherapy, who was successfully managed by PM surgery. A review of the literature completes our observation. At presentation, the patient had a spherical equivalent of - 7.50 RE and - 7.75 LE with an IOP of 22 mmHg right and left eye (RLE) under quadritherapy, and with severe bilateral visual field loss, including scotomas within the central 5°. The patient presented with systemic hypertension treated with an antihypertensive drug. Two selective laser trabeculoplasties (SLT), performed 3 months apart, were first tried on the LE, without any change in IOP at 2 months. After considering the high risk of postoperative complications, a PM operation was proposed, with a targeted IOP in the mid-fifteens RLE. The patient's eyes underwent PM surgery with mitomycin C (MMC) MMC0.2 mg/mL for 3 minutes without any complications. The LE required 2 consecutive needlings with 1 mL MMC0.2 mg/mL. At 24 months after surgery, the two eyes gave successful results without the need for any additional medical therapy, and with well-functioning conjunctival blebs. The PM was an effective alternative to the gold standard trabeculectomy in our severely myopic patient. A comparative study between conventional filtering operations and this MIBS in highly myopic patients would confirm our observation.

Comparison of Structural and Functional Features in Primary Angle Closure and Open Angle Glaucomas

PRCIS

Using a large data set, we showed structural and functional differences between primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG). Primary angle closure glaucoma has relative structural preservation and worse functional loss inferiorly.

PURPOSE

To identify structural and functional differences in PACG and POAG.

MATERIALS AND METHODS

In this large cross-sectional study, differences in structural and functional damage were assessed among patients with POAG and PACG with optical coherence tomography and reliable visual field testing.

RESULTS

In all, 283 patients with PACG and 4110 patients with POAG were included. Despite similar mean deviation on visual fields (mean [SD] -7.73 [7.92] vs. -7.53 [6.90] dB, P =0.72), patients with PACG had thicker global retinal nerve fiber layer (RNFL), smaller cup volume, smaller cup-to-disc ratio, and larger rim area than POAG (77 [20] vs. 71 [14] µm, 0.32 [0.28] vs. 0.40 [0.29] mm 3 , 0.6 [0.2] vs. 0.7 [0.1], 1.07 [0.40] vs. 0.89 [0.30] mm 2 , P <0.001 for all), while patients with POAG had more pronounced inferior RNFL thinning (82 [24] vs. 95 [35] µm, P <0.001). In a multivariable analysis, hyperopia [odds ratio (OR): 1.24, confidence interval (CI): 1.13-1.37], smaller cup-to-disc ratio (OR: 0.69, CI: 0.61-0.78), thicker inferior RNFL (OR: 1.15, CI: 1.06-1.26) and worse mean deviation (OR: 0.95, CI: 0.92-0.98) were associated with PACG. Functionally, POAG was associated with superior paracentral loss and PACG with inferior field loss. After adjusting for average RNFL thickness, PACG was associated with more diffuse loss than POAG (total deviation differences 1.26-3.2 dB).

CONCLUSIONS

Patients with PACG had less structural damage than patients with POAG despite similar degrees of functional loss. Regional differences in patterns of functional and structural loss between POAG and PACG may improve disease monitoring for these glaucoma subtypes.

Three-dimensional choroidal contour mapping in healthy population

Purpose was to study 3-dimensional choroidal contour at choroidal inner boundary (CIB) and choroidal outer boundary (COB) in healthy eyes. Healthy eyes imaged on wide field swept-source optical coherence tomography were included. Delineation of CIB and COB was done based on our previously reported methods. Quantitative analysis of the surfaces of CIB and COB was based on analyzing best fit spherical radius (R) (overall and sectoral). One hundred and seven eyes of 74 subjects with a mean age of 46.4 ± 19.3 years were evaluated. Overall, R COB (mean ± SD: 22.5 ± 4.8 mm) < R CIB (32.4 ± 9.4 mm). Central sector had the least R at COB (7.2 ± 5.9 mm) as well as CIB (25.1 ± 14.3 mm) across all age groups. Regression analysis between R (CIB) and age (r = -0.31, r2 = 0.09) showed negative correlation (P < 0.001) and that between R (COB) and age was positive (r = 0.26, r2 = 0.07) (P = 0.01). To conclude, central sector is the steepest sector in comparison to all the other sectors. This is indicative of a prolate shape of choroidal contour at CIB and COB. Outer boundary of choroid is steeper than inner boundary across all age groups. However, with ageing, outer boundary becomes flatter and inner boundary becomes steeper.

Myopia progression patterns among paediatric patients in a clinical setting

PURPOSE

This retrospective analysis of electronic medical record (EMR) data investigated the natural history of myopic progression in children from optometric practices in Ireland.

METHODS

The analysis was of myopic patients aged 7-17 with multiple visits and not prescribed myopia control treatment. Sex- and age-specific population centiles for annual myopic progression were derived by fitting a weighted cubic spline to empirical quantiles. These were compared to progression rates derived from control group data obtained from 17 randomised clinical trials (RCTs) for myopia. Linear mixed models (LMMs) were used to allow comparison of myopia progression rates against outputs from a predictive online calculator. Survival analysis was performed to determine the intervals at which a significant level of myopic progression was predicted to occur.

RESULTS

Myopia progression was highest in children aged 7 years (median: -0.67 D/year) and progressively slowed with increasing age (median: -0.18 D/year at age 17). Female sex (p < 0.001), a more myopic SER at baseline (p < 0.001) and younger age (p < 0.001) were all found to be predictive of faster myopic progression. Every RCT exhibited a mean progression higher than the median centile observed in the EMR data, while clinic-based studies more closely matched the median progression rates. The LMM predicted faster myopia progression for patients with higher baseline myopia levels, in keeping with previous studies, which was in contrast to an online calculator that predicted slower myopia progression for patients with higher baseline myopia. Survival analysis indicated that at a recall period of 12 months, myopia will have progressed in between 10% and 70% of children, depending upon age.

CONCLUSIONS

This study produced progression centiles of untreated myopic children, helping to define the natural history of untreated myopia. This will enable clinicians to better predict both refractive outcomes without treatment and monitor treatment efficacy, particularly in the absence of axial length data.

Intraocular pressure variation from ocular compression in low and high myopia

CLINICAL RELEVANCE

Change in intraocular pressure during acute ocular compression is related to aqueous humour dynamics. Monitoring intraocular pressure (IOP) change throughout ocular compression has potential to evaluate aqueous outflow facilities.

BACKGROUND

Recent studies have monitored lamina cribrosa deformation using optical coherence tomography during ocular compression. IOP was measured only once immediately after ocular compression. This study aimed to evaluate IOP changes during and after ocular compression and compare the differences between low and high myopia.

METHODS

Two groups of young, healthy adults were age-matched and underwent ocular compression. IOP was measured at baseline and monitored during a 2-min ocular compression followed by a 10-min recovery phase. Rebound tonometry was used and applied at 30-s intervals.

RESULTS

Thirty low and 30 high myopes (60 right eyes) were included in the study. They had similar baseline IOP at 14.9 mmHg. IOP was elevated to 21.7 ± 3.8 mmHg and 22.3 ± 4.2 mmHg for the low and high myopic group, respectively (p = 0.877). Low myopes had faster IOP decay during ocular compression at -3.24 mmHg/min than high myopes at -2.58 mmHg/min (p = 0.0528). The IOP dropped below the baseline level after the release of the compressive force. Low myopes had IOP that returned to baseline levels faster (at 360 s) than high myopes (at 510 s).

CONCLUSION

Measuring IOP once immediately after ocular compression could under-estimate the effect of IOP elevation during ocular compression. Further studies are required regarding IOP changes from ocular compression in aqueous humour dynamics.

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.

The Effects of Lens Extraction Surgery on Intraocular Pressure and Anterior Segment Parameters in Primary Angle-Closure Glaucoma

Objectives

To investigate the effects of phacoemulsification with intraocular lens implantation (phaco+IOL) surgery on intraocular pressure (IOP) and anterior segment parameters in patients with cataract and primary angle-closure glaucoma (PACG).

Materials and Methods

Fifty-five patients with PACG undergoing phaco+IOL surgery were evaluated in terms of best corrected visual acuity (BCVA), IOP, anterior chamber depth (ACD), aqueous depth (AD), and lens thickness (LT) measured by optical biometry preoperatively and at the 6-month postoperative visit. They were compared with 34 healthy age-and gender-matched cataract patients who underwent phaco+IOL surgery.

Results

Preoperative evaluation revealed higher IOP, shorter axial length, shallower ACD and AD, and greater LT in the PACG group (p<0.001 for all). Postoperative evaluation in the PACG group showed an increase in BCVA, a significant decrease in IOP, an increase in ACD and AD, and a decrease in LT (p<0.001 for all). Additionally, a reduction in the average number of antiglaucomatous medications used postoperatively was observed in the PACG group (p<0.001). The changes in IOP, ACD, AD, and LT between preoperative and postoperative assessments were significantly greater in the PACG group compared to the control group (p<0.0001 for all).

Conclusion

Phaco+IOL surgery in PACG patients leads to a significant increase in ACD compared to the control group and allows better control of IOP with fewer antiglaucomatous medications after surgery.

Genetic Basis of Pigment Dispersion Syndrome and Pigmentary Glaucoma: An Update and Functional Insights

Pigment Dispersion Syndrome (PDS) and Pigmentary Glaucoma (PG) comprise a spectrum of ocular disorders characterized by iris pigment dispersion and trabecular meshwork changes, resulting in increased intraocular pressure and potential glaucomatous optic neuropathy. This review summarizes recent progress in PDS/PG genetics including rare pathogenic protein coding alterations (PMEL) and susceptibility loci identified from genome-wide association studies (GSAP and GRM5/TYR). Areas for future research are also identified, especially the development of efficient model systems. While substantial strides have been made in understanding the genetics of PDS/PG, our review identifies key gaps and outlines the future directions necessary for further advancing this important field of ocular genetics.

Deep Transfer Learning for Ethnically Distinct Populations: Prediction of Refractive Error Using Optical Coherence Tomography

INTRODUCTION

The mismatch between training and testing data distribution causes significant degradation in the deep learning model performance in multi-ethnic scenarios. To reduce the performance differences between ethnic groups and image domains, we built a deep transfer learning model with adaptation training to predict uncorrected refractive errors using posterior segment optical coherence tomography (OCT) images of the macula and optic nerve.

METHODS

Observational, cross-sectional, multicenter study design. We pre-trained a deep learning model on OCT images from the B&VIIT Eye Center (Seoul, South Korea) (N = 2602 eyes of 1301 patients). OCT images from Poona Eye Care (Pune, India) were chronologically sorted into adaptation training data (N = 60 eyes of 30 patients) for transfer learning and test data (N = 142 eyes of 71 patients) for validation. Deep learning models were trained to predict spherical equivalent (SE) and mean keratometry (K) values via transfer learning for domain adaptation.

RESULTS

Both adaptation models for SE and K were significantly better than those without adaptation (P < 0.001). In myopia/hyperopia classification, the model trained on circular optic disc OCT images yielded the best performance (accuracy = 74.7%). It also performed best in estimating SE with the lowest mean absolute error (MAE) of 1.58 D. For classifying the degree of corneal curvature, the optic nerve vertical algorithm performed best (accuracy = 65.7%). The optic nerve horizontal model achieved the lowest MAE (1.85 D) when predicting the K value. Saliency maps frequently highlighted the retinal nerve fiber layers.

CONCLUSIONS

Adaptation training via transfer learning is an effective technique for estimating refractive errors and K values using macular and optic nerve OCT images from ethnically heterogeneous populations. Further studies with larger sample sizes and various data sources are needed to confirm the feasibility of the proposed algorithm.

Particular Anatomy of the Hyperopic Eye and Potential Clinical Implications

Background and Objectives: Hyperopia is a refractive error which affects cognitive and social development if uncorrected and raises the risk of primary angle-closure glaucoma (PACG). Materials and Methods: The study included only the right eye-40 hyperopic eyes in the study group (spherical equivalent (SE) under pharmacological cycloplegia over 0.50 D), 34 emmetropic eyes in the control group (SE between -0.50 D and +0.50 D). A complete ophthalmological evaluation was performed, including autorefractometry to measure SE, and additionally we performed Ocular Response Analyser: Corneal Hysteresis (CH), Corneal Resistance Factor (CRF); specular microscopy: Endothelial cell density (CD), Cell variability (CV), Hexagonality (Hex), Aladdin biometry: Anterior Chamber Depth (ACD), Axial Length (AL), Central Corneal Thickness (CCT). IBM SPSS 26 was used for statistical analysis. Results: The mean age of the entire cohort was 22.93 years (SD ± 12.069), 66.22% being female and 33.78% male. The hyperopic eyes had significantly lower AL, ACD, higher SE, CH, CRF. In the hyperopia group, there are significant, negative correlations between CH and AL (r -0.335), CRF and AL (r -0.334), SE-AL (r -0.593), ACD and CV (r -0.528), CV and CRF (r -0.438), CH (r -0.379), and positive correlations between CCT and CH (r 0.393) or CRF (r 0.435), CD and ACD (r 0.509) or CH (0.384). Age is significantly, negatively correlated with ACD (r -0.447), CH (r -0.544), CRF (r -0.539), CD (r -0.546) and positively with CV (r 0.470). Conclusions: Our study suggests a particular biomechanical behavior of the cornea in hyperopia, in relation with morphological and endothelial parameters. Moreover, the negative correlation between age and ACD suggests a shallower anterior chamber as patients age, increasing the risk for PACG.

Risk Factors for Primary Angle-closure Glaucoma: A Systematic Review and Meta-analysis of 45 Studies

SIGNIFICANCE

This study summarized primary angle-closure glaucoma (PACG)-related factors across different dimensions.

OBJECTIVES

This review aimed at systematically summarizing the associated factors of PACG in published literatures.

METHODS

A systematic review and meta-analysis were conducted by searching the electronic databases including PubMed, EMBASE, and Web of Science from their inception to November 2021. The pooled risk estimates of continuous and categorical variables were calculated using weighted mean difference (WMD) and odds ratio (OR; 95% confidence intervals [CIs]), respectively.

RESULTS

We included 45 studies in this review. In the meta-analysis, intraocular pressure (WMD, 3.13; 95% CI, 2.37 to 3.89), anterior chamber depth (WMD, -0.52; 95% CI, -0.70 to -0.34), axial length (WMD, -0.77; 95% CI, -1.26 to -0.28), retinal nerve fiber layer (WMD, -21.23; 95% CI, -30.21 to -12.25), and spherical equivalent (WMD, 1.02; 95% CI, 0.66 to 1.38) were the most common ophthalmic anatomic factors, and lower body weight (WMD, -3.65; 95% CI, -6.48 to -0.82) was the most significant general morphological indicators. The presence of cataract (OR, 3.77; 95% CI, 3.46 to 4.11) and hyperlipidemia (OR, 1.10; 95% CI, 1.02 to 1.20) were significantly associated with PACG. Increased level of triglyceride (WMD, 0.17; 95% CI, 0.06 to 0.27) was associated with PACG. In addition, an association between short-term antidepressant exposure (OR, 1.36; 95% CI, 1.08 to 1.70) and acute angle-closure glaucoma was observed.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

This review identified a few consistent factors related to PACG, providing important information for primary care physicians, general ophthalmologists, and public health professionals to counsel their patients on PACG risks.

Comparison of Corvis ST Parameters between Primary Open-Angle Glaucoma and Primary Angle-Closure Glaucoma

BACKGROUND

We compared corneal visualization Scheimpflug technology (CST) parameters between eyes with primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG).

METHODS

A retrospective analysis was performed on data from 89 eyes with POAG and 83 eyes with PACG that had CST examinations. CST parameters were compared between eyes with POAG and those with PACG using a linear mixed model (LMM).

RESULTS

No differences were observed in age, central corneal thickness, intraocular pressure, or use of antiglaucoma eye drops between the two groups. Patients with PACG had a significantly shorter axial length (AL), a higher proportion of females, CST parameters, longer applanation 2 (A2) time, deeper A2 deformation amplitude, shorter peak distance, longer whole eye movement, and longer whole eye movement time than patients with POAG. The highest concavity (HC) length and PD showed a significant positive correlation with AL. However, A1 length, A1 deformation amplitude, A2 time, A2 velocity, A2 length, A2 deformation amplitude, HC time, whole eye movement, and whole eye movement time were negatively correlated with AL.

CONCLUSIONS

The biomechanical properties of the cornea differed between POAG and PACG. In some parts, AL differences between the POAG and PACG groups might contribute to the variation in CST parameters.

How Myopia and Glaucoma Influence the Biomechanical Susceptibility of the Optic Nerve Head

PURPOSE

The purpose of this study was to assess optic nerve head (ONH) deformations following acute intraocular pressure (IOP) elevations and horizontal eye movements in control eyes, highly myopic (HM) eyes, HM eyes with glaucoma (HMG), and eyes with pathologic myopia (PM) alone or PM with staphyloma (PM + S).

METHODS

We studied 282 eyes, comprising of 99 controls (between +2.75 and -2.75 diopters), 51 HM (< -5 diopters), 35 HMG, 21 PM, and 75 PM + S eyes. For each eye, we imaged the ONH using spectral-domain optical coherence tomography (OCT) under the following conditions: (1) primary gaze, (2) 20 degrees adduction, (3) 20 degrees abduction, and (4) primary gaze with acute IOP elevation (to ∼35 mm Hg) achieved through ophthalmodynamometry. We then computed IOP- and gaze-induced ONH displacements and effective strains. Effective strains were compared across groups.

RESULTS

Under IOP elevation, we found that HM eyes exhibited significantly lower strains (3.9 ± 2.4%) than PM eyes (6.9 ± 5.0%, P < 0.001), HMG eyes (4.7 ± 1.8%, P = 0.04), and PM + S eyes (7.0 ± 5.2%, P < 0.001). Under adduction, we found that HM eyes exhibited significantly lower strains (4.8% ± 2.7%) than PM + S eyes (6.0 ± 3.1%, P = 0.02). We also found that eyes with higher axial length were associated with higher strains.

CONCLUSIONS

Our study revealed that eyes with HMG experienced significantly greater strains under IOP compared to eyes with HM. Furthermore, eyes with PM + S had the highest strains on the ONH of all groups.

Refractive surgery for the glaucoma suspect

PURPOSE OF REVIEW

The aim of this study was to provide an update on perioperative considerations in the evaluation and management of patients undergoing primary corneal and intraocular refractive procedures who are at risk for progressive glaucomatous optic neuropathy.

RECENT FINDINGS

The necessity of a comprehensive baseline assessment prior to refractive procedures with structural and functional testing, along with documentation of preoperative intraocular pressure (IOP) measurements, is highlighted in recent literature. Substantiation of the increased risk of postoperative IOP elevation in keratorefractive procedures in patients with higher baseline IOP and lower baseline CCT, but not necessarily the degree of myopia, has been variably evidenced. Tonometry methods which are less influenced by postoperative corneal structural change should be considered in patients undergoing keratorefractive procedures. Vigilence in postoperative monitoring for progressive optic neuropathy is suggested given evidence of an increased risk of steroid-response glaucoma in these patients. Additional evidence for the IOP-lowering impact of cataract surgery in patients with an increased risk of glaucoma is provided, irrespective of intraocular lens choice.

SUMMARY

Performing refractive procedures on patients at risk for glaucoma remains controversial. Definitive steps to optimize patient selection along with vigilance in disease state monitoring with longitudinal structural and functional testing can help mitigate potential adverse events.

Racial and Ethnic Differences in the Roles of Myopia and Ocular Biometrics as Risk Factors for Primary Open-Angle Glaucoma

Purpose

Assess how the roles of refractive error (RE) and ocular biometrics as risk factors for primary open-angle glaucoma (POAG) differ by race and ethnicity.

Methods

Data from the Los Angeles Latino Eye Study (LALES) and the Chinese American Eye Study (CHES), two population-based epidemiological studies, were retrospectively analyzed. Multivariable logistic regression and interaction term analyses were performed to assess relationships between POAG and its risk factors, including RE and axial length (AL), and to assess effect modification by race/ethnicity.

Results

Analysis included 7601 phakic participants of LALES (47.3%) and CHES (52.7%) with age ≥ 50 years. Mean age was 60.6 ± 8.3 years; 60.9% were female. The prevalence and unadjusted risk of POAG were higher in LALES than CHES (6.0% and 4.0%, respectively; odds ratio [OR] = 1.55; P < 0.001). In the multivariable analysis, significant risk factors for POAG included Latino ethnicity (OR = 2.25; P < 0.001), refractive myopia (OR = 1.54 for mild, OR = 2.47 for moderate, OR = 3.94 for high compared to non-myopes; P ≤ 0.003), and longer AL (OR = 1.37 per mm; P < 0.001). AL (standardized regression coefficient [SRC] = 0.3) was 2.7-fold more strongly associated with POAG than high myopia status (SRC = 0.11). There was no modifying effect by race/ethnicity on the association between RE (per diopter) or AL (per millimeter) and POAG (P = 0.49).

Conclusions

Although the POAG risk conferred by myopic RE and longer AL is similar between Latino and Chinese Americans, the difference in POAG prevalence between the two groups is narrowed by higher myopia prevalence among Chinese Americans. Racial/ethnic populations with higher myopia incidence may become disproportionately affected by POAG in the context of the global myopia epidemic.

Exogenous All-Trans Retinoic Acid Induces Myopia and Alters Scleral Biomechanics in Mice

Purpose

Ocular all-trans retinoic acid (atRA) levels are influenced by visual cues, and exogenous atRA has been shown to increase eye size in chickens and guinea pigs. However, it is not clear whether atRA induces myopic axial elongation via scleral changes. Here, we test the hypothesis that exogenous atRA will induce myopia and alter scleral biomechanics in the mouse.

Methods

Male C57BL/6J mice were trained to voluntarily ingest atRA + vehicle (1% atRA in sugar, 25 mg/kg) (RA: n = 16 animals) or vehicle only (Ctrl: n = 14 animals). Refractive error (RE) and ocular biometry were measured at baseline and after 1 and 2 weeks of daily atRA treatment. Eyes were used in ex vivo assays to measure scleral biomechanics (unconfined compression: n = 18), total scleral sulfated glycosaminoglycan (sGAG) content (dimethylmethylene blue: n = 23), and specific sGAGs (immunohistochemistry: n = 18).

Results

Exogenous atRA caused myopic RE and larger vitreous chamber depth (VCD) to develop by 1 week (RE: -3.7 ± 2.2 diopters [D], P < 0.001; VCD: +20.7 ± 15.1 µm, P < 0.001), becoming more severe by 2 weeks (RE: -5.7 ± 2.2 D, P < 0.001; VCD: +32.3 ± 25.8 µm, P < 0.001). The anterior eye biometry was unaffected. While scleral sGAG content was not measurably affected, scleral biomechanics were significantly altered (tensile stiffness: -30% ± 19.5%, P < 0.001; permeability: +60% ± 95.3%, P < 0.001).

Conclusions

In mice, atRA treatment results in an axial myopia phenotype. Eyes developed myopic RE and larger VCD without the anterior eye being affected. The decrease in stiffness and increase in permeability of the sclera are consistent with the form-deprivation myopia phenotype.

Relatively anterior lens position in primary angle-closure glaucoma eyes with long axial length

Purpose

To evaluate the refractive status and ocular biometric parameters in primary angle-closure glaucoma (PACG) eyes with different axial lengths (ALs).

Methods

In total, 742 Chinese PACG subjects with complete ophthalmic examinations were enrolled. The refractive status was categorized as myopia (spherical equivalent [SE] ≤-0.5 D), emmetropia (-0.5 D < SE < +0.5 D), and hyperopia (SE ≥+0.5 D), whereas the AL was divided into short (AL <22.5 mm), regular (22.5 ≤ AL <23.5 mm), and long (AL ≥23.5 mm). The refractive status and ocular biometric parameters were compared among different AL groups.

Results

The mean AL of the PACG eyes was 22.53 ± 0.84 mm (range: 19.68-25.57 mm). The refractive status was significantly different among different AL groups (P < 0.001). Also, 92.6% of hyperopic PACG eyes showed AL <23.5 mm, and 19.0% of myopic PACG eyes showed AL ≥23.5 mm. The SE showed significant differences among different AL groups only in the hyperopic subjects (P = 0.012). The AL was significantly longer in myopic eyes (P < 0.001). The PACG eyes with longer AL exhibited lower keratometry, longer central anterior chamber depth and corneal diameter, and lens position and relative lens position closer to the anterior (P < 0.001).

Conclusion

Axial hyperopia was common in PACG eyes, and axial myopia was not uncommon. Relatively anterior lens position could explain the occurrence of PACG in the eyes with long AL.

Refractive Error and Anterior Chamber Depth as Risk Factors in Primary Angle Closure Disease: The Chinese American Eye Study

PRCIS

The risk of primary angle closure disease (PACD) rises rapidly with greater hyperopia while remaining relatively low for all degrees of myopia. Refractive error (RE) is useful for angle closure risk stratification in the absence of biometric data.

PURPOSE

To assess the role of RE and anterior chamber depth (ACD) as risk factors in PACD.

METHODS

Chinese American Eye Study participants received complete eye examinations including refraction, gonioscopy, amplitude-scan biometry, and anterior segment ocular coherence tomography imaging. PACD included primary angle closure suspect (≥3 quadrants of angle closure on gonioscopy) and primary angle closure/primary angle closure glaucoma (peripheral anterior synechiae or intraocular pressure >21 mm Hg). Logistic regression models were developed to assess associations between PACD and RE and/or ACD adjusted for sex and age. Locally weighted scatterplot smoothing curves were plotted to assess continuous relationships between variables.

RESULTS

Three thousand nine hundred seventy eyes (3403 open angle and 567 PACD) were included. The risk of PACD increased with greater hyperopia [odds ratio (OR) = 1.41 per diopter (D); P < 0.001] and shallower ACD (OR = 1.75 per 0.1 mm; P < 0.001). Hyperopia (≥ + 0.5 D; OR = 5.03) and emmetropia (-0.5 D to +0.5 D; OR = 2.78) conferred a significantly higher risk of PACD compared with myopia (≤0.5 D). ACD (standardized regression coefficient = -0.54) was a 2.5-fold stronger predictor of PACD risk compared with RE (standardized regression coefficient = 0.22) when both variables were included in one multivariable model. The sensitivity and specificity of a 2.6 mm ACD cutoff for PACD were 77.5% and 83.2% and of a +2.0 D RE cutoff were 22.3% and 89.1%.

CONCLUSION

The risk of PACD rises rapidly with greater hyperopia while remaining relatively low for all degrees of myopia. Although RE is a weaker predictor of PACD than ACD, it remains a useful metric to identify patients who would benefit from gonioscopy in the absence of biometric data.

Artificial Intelligence for Anterior Segment Diseases: A Review of Potential Developments and Clinical Applications

Artificial intelligence (AI) technology is promising in the field of healthcare. With the developments of big data and image-based analysis, AI shows potential value in ophthalmology applications. Recently, machine learning and deep learning algorithms have made significant progress. Emerging evidence has demonstrated the capability of AI in the diagnosis and management of anterior segment diseases. In this review, we provide an overview of AI applications and potential future applications in anterior segment diseases, focusing on cornea, refractive surgery, cataract, anterior chamber angle detection, and refractive error prediction.

Analysis of the reports of low-concentration atropine in controlling myopia in children

PURPOSE

To evaluate the efficacy of 0.01% atropine to slow the progression of myopia in children.

METHODS

We searched PubMed, Embase, ClinicalTrials.gov, CNKI, Cqvip and Wan fang databases from inception to January 2022, including RCTs (randomized controlled trials) and non-RCTs (non-randomized controlled trials). The search strategy was 'myopia' OR 'refractive error' and 'atropine.' Two researchers independently reviewed the articles, and stata12.0 was used for meta-analysis. The Jadad score was used to assess the quality of RCT, and the Newcastle-Ottawa scale was used for non-RCTs.

RESULTS

Five RCTs and two non-RCTs (1 prospective non-randomized controlled study, 1 retrospective cohort study) were identified (including 1000 eyes). Results of the meta-analysis showed statistical heterogeneity among the 7 included studies (P=0. 026, I2 =47.1%). According to different durations of atropine use - 4 months, 6 months and greater than 8 months, subgroup analysis results showed that the axial elongation of all experimental groups relative to control groups were respectively -0.03mm (95% [CI], (confidence interval), -0.07 to 0.01), -0.07mm (95% [CI], -0.10 to -0.05), -0.09mm (95% [CI], -0.12 to -0.06). Each P was greater than 0.05, which indicated that there is little heterogeneity among the subgroups.

CONCLUSIONS

In this meta-analysis of the short-term efficacy of atropine in myopia patients, it was found that there was little heterogeneity when grouped by usage time. It is suggested that the use of atropine in the treatment of myopia is not only related to its concentration but also related to the duration of use.

Combined 0.01% atropine with orthokeratology in childhood myopia control (AOK) study: A 2-year randomized clinical trial

BACKGROUND

To investigate whether combining 0.01% atropine with orthokeratology (AOK) has a better effect in retarding axial elongation, compared with orthokeratology alone (OK) over two years.

METHODS

A total of 96 Chinese children aged six to < 11 years with myopia (1.00 - 4.00 D, inclusive) were randomized into either the AOK or OK group in a 1:1 ratio. Axial length (the primary outcome), and secondary outcomes (e.g. pupil size and choroidal thickness) were measured at 1-month and at 6-monthly intervals after commencement of treatment.

RESULTS

Both intention-to-treat and per-protocol analyses showed significantly slower axial elongation in the AOK group than OK group over two years (P = 0.008, P < 0.001, respectively). AOK subjects had statistically slower axial elongation (adjusted mean [standard error], 0.17 [0.03] mm vs 0.34 [0.03] mm, P < 0.001), larger increase in mesopic (0.70 [0.09] mm vs 0.31 [0.09] mm, P = 0.003) and photopic pupil size (0.78 [0.07] mm vs 0.23 [0.07] mm, P < 0.001), and greater thickening of the choroid (22.6 [3.5] µm vs -9.0 [3.5] µm, P < 0.001) than OK subjects over two years. Except for a higher incidence of photophobia in the AOK group (P = 0.006), there were no differences in the incidence of any other symptom or adverse events between the two groups. Slower axial elongation was associated with a larger increase in the photopic pupil size and a greater thickening in the choroid in the AOK group.

CONCLUSIONS

Slower axial elongation following 2-year AOK treatment may result from increased pupil dilation and a thickening in the choroid observed in the AOK group.

Success rate in micropulse diode laser treatment with regard to lens status, refractive errors, and glaucoma subtypes

PURPOSE

To evaluate the efficacy of micropulse transscleral cyclophotocoagulation (MP-TSCPC) considering different characteristics: glaucoma subtypes and lens status.

METHODS

A retrospective case-series study was designed to evaluate intraocular pressure (IOP), and the number of IOP-lowering medications, used by glaucoma patients treated with MP-TSCPC between 2016 and 2019. Cases had a follow-up period of 12 months. Achieving an IOP reduction higher than 20%, or the decrease of at least one IOP-lowering medication, was considered a successful outcome. The same population was analyzed by classifying them in two groups as: glaucoma subtypes and lens status. The baseline spherical equivalent (SE) was also calculated for considering association with the achieved IOP.

RESULTS

A total of 86 eyes were included. In most cases, IOP and IOP-lowering medications were decreased with a statistically significant difference (p < 0.0001), and all of them had a successful outcome. The percentage of IOP drop oscillated between 25.9% (open-angle glaucoma sub-group) and 37.5% (pseudoexfoliative glaucoma sub-group), 12 months after surgery. The difference between the groups was not statistically significant (p 0.20 and 0.32 for glaucoma subtypes and lens status, respectively). The Pearson's coefficient obtained was low for the SE and IOP association, at the 12 -month postoperative mark (- 0.009; p < 0.001).

CONCLUSIONS

The MP-TSCPC treatment was successful in decreasing IOP and IOP-lowering medications, in different glaucoma subtypes. Differences between groups (glaucoma subtypes, phakic and pseudophakic eyes) were not statistically significant. No association was found between the SE and the IOP achieved value after MS-TSCPC treatment.

The Efficacy of Defocus Incorporated Multiple Segments Lenses in Slowing Myopia Progression: Results from Diverse Clinical Circumstances

PURPOSE

Defocus incorporated multiple segments (DIMS) spectacle lenses were reported to slow myopia progression significantly in a randomized controlled trial (RCT). The study evaluated their effectiveness in clinical settings.

DESIGN

Retrospective study.

PARTICIPANTS

Patient records involving use of DIMS and single-vision (SV) spectacle lenses were collected from subsidiary hospitals of Aier Eye Hospital Group.

METHODS

The spherical equivalent (SE), determined by subjective refraction, was adopted to assess the myopia progression. The strategy of propensity score matching (PSM) was applied to match the confounding baseline characteristics between the 2 groups. The effectiveness was calculated based on the difference of myopia progression of these 2 approaches.

MAIN OUTCOME MEASURES

Change in SE.

RESULTS

Three thousand six hundred thirty-nine patients with DIMS and 6838 patients with SV spectacles were included. The age of the patients was 6 to 16 years (mean ± standard deviation: 11.02 ± 2.53 years). The baseline SE was between 0.00 and -10.00 diopters (D) (mean ± standard deviation: -2.78 ± 1.74 D). After the PSM, data on 2240 pairs with 1-year follow-up and on 735 pairs with 2-year follow-up were obtained. Significantly slower progression was seen in the DIMS group at both the 1-year (DIMS, -0.50 ± 0.43 D; SV, -0.77 ± 0.58 D; P < 0.001) and 2-year (DIMS, -0.88 ± 0.62 D; SV, -1.23 ± 0.76 D; P < 0.001) subdataset. In the 1-year subdataset, 40% and 19% showed myopia progression of no more than 0.25 D for the DIMS and SV groups, respectively (chi-square, 223.43; P < 0.001), whereas 9% and 22% showed myopia progression of more than 1.00 D for the DIMS and SV groups, respectively (chi-square, 163.38; P < 0.001). In the 2-year subdataset, 33% and 20% showed myopia progression of no more than 0.50 D for the DIMS and SV groups, respectively (chi-square, 31.15; P < 0.001), whereas 12% and 29% showed myopia progression of more than 1.50 D for the DIMS and SV groups (chi-square, 65.60; P < 0.001).

CONCLUSIONS

Although the magnitude was lower than that reported in the previous RCT, this large-scale study with diversity of the data sources confirmed the effectiveness of DIMS spectacles to slow myopia progression in clinical practice.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Anterior Segment Characteristics and Risk Factors for Primary Angle Closure Disease With Long Axial Lengths: The Handan Eye Study

Purpose

To investigate the anterior segment characteristics of primary angle closure disease (PACD) with long axial length (AL) compared with that of those with short and medium AL and explore the risk factors associated with AC with different AL levels.

Methods

This observational cross-sectional study enrolled subjects aged 35 years or older who completed the follow-up examinations of the Handan Eye Study and dichotomized them into normal and PACD groups. Ocular data of the right eye were analyzed. AL was categorized into short (<22.0 mm), medium (22.0-24.0 mm), or long (>24.0 mm) subgroups. Demographic and anterior segment parameters of PACD subjects were compared between the three AL subgroups. Logistic regression analysis was performed to identify the risk factors for PACD in the three subgroups.

Results

Data from 715 PACD and 1446 normal subjects were analyzed. Only 6.6% of the PACD eyes had long AL, with lower spherical equivalent, larger anterior chamber depth (P < 0.001), and smaller lens thickness (P < 0.001) than those with short and medium AL. No significant differences were found for angle opening distance and iris parameters on comparing the values of eyes with long AL with that of those with short and medium AL. Significant risk factors for the development of PACD with long AL were peripheral iris thickness, anterior chamber width, and lens vault.

Conclusions

PACD with long AL was uncommon. A thicker peripheral iris, larger lens vault, and smaller ACW contributed to angle closure in these patients.

Altered Structure and Function of Murine Sclera in Form-Deprivation Myopia

Purpose

The sclera is believed to biomechanically influence eye size, facilitating the excessive axial elongation that occurs during myopigenesis. Here, we test the hypothesis that the sclera will be remodeled and exhibit altered biomechanics in the mouse model of form-deprivation (FD) myopia, accompanied by altered retinoid concentrations, a potential signaling molecule involved in the process.

Methods

Male C57 Bl/6J mice were subjected to unilateral FD (n = 44 eyes), leaving the contralateral eye untreated (contra; n = 44). Refractive error and ocular biometry were measured in vivo prior to and after 1 or 3 weeks of FD. Ex vivo measurements were made of scleral biomechanical properties (unconfined compression: n = 24), scleral sulfated glycosaminoglycan (sGAG) content (dimethylmethylene blue: n = 18, and immunohistochemistry: n = 22), and ocular all-trans retinoic acid (atRA) concentrations (retina and RPE + choroid + sclera, n = 24). Age-matched naïve controls were included for some outcomes (n = 32 eyes).

Results

Significant myopia developed after 1 (-2.4 ± 1.1 diopters [D], P < 0.001) and 3 weeks of FD (-4.1 ± 0.7 D, P = 0.025; mean ± standard deviation). Scleral tensile stiffness and permeability were significantly altered during myopigenesis (stiffness = -31.4 ± 12.7%, P < 0.001, and permeability = 224.4 ± 205.5%, P < 0.001). Total scleral sGAG content was not measurably altered; however, immunohistochemistry indicated a sustained decrease in chondroitin-4-sulfate and a slower decline in dermatan sulfate. The atRA increased in the retinas of eyes form-deprived for 1 week.

Conclusions

We report that biomechanics and GAG content of the mouse sclera are altered during myopigenesis. All scleral outcomes generally follow the trends found in other species and support a retina-to-sclera signaling cascade underlying mouse myopigenesis.

Ocular morphologic traits in the American Cocker Spaniel may confer primary angle closure glaucoma susceptibility

Acute primary angle closure glaucoma is a potentially blinding ophthalmic emergency requiring prompt treatment to lower the elevated intraocular pressure in humans and dogs. The PACG in most of canine breeds is epidemiologically similar to humans with older and female patients overrepresented with the condition. The American Cocker Spaniel (ACS) is among the most common breeds observed with PACG development in dogs. This study initially sought to identify genetic risk factors to explain the high prevalence of PACG in ACSs by using a case-control breed-matched genome-wide association study. However, the GWAS failed to identify candidate loci associated with PACG in this breed. This study then assessed intrinsic ocular morphologic traits that may relate to PACG susceptibility in this breed. Normal ACSs without glaucoma have a crowded anterior ocular segment and narrow iridocorneal angle and ciliary cleft, which is consistent with anatomical risk factors identified in humans. The ACSs showed unique features consisting of posterior bowing of iris and longer iridolenticular contact, which mirrors reverse pupillary block and pigment dispersion syndrome in humans. The ACS could hold potential to serve as an animal model of naturally occurring PACG in humans.

A Study Linking Axial Length, Corneal Curvature, and Eye Axis With Demographic Characteristics in the Emmetropic Eyes of Bangladeshi People

Background Axial length (AL) and corneal curvature (CC) are one of the furthest critical parameters for optometry and oculoplastic surgery. These two variables are crucial in biometry for accurately measuring the power of the intraocular lens in cataract surgery. This research aimed to determine the association linking axial length and corneal curvature with demographic characteristics in emmetropic eyes of Bangladeshi people. Methods This descriptive cross-sectional research was carried out among 200 emmetropic eyes of Bangladeshi people attending the Department of Ophthalmology at Rajshahi Medical College, Bangladesh, with different eye conditions, between July 2017 and June 2018. Data was gathered by conducting person-to-person interviews, checking visual activity using the Snellen chart, and measuring corneal curvature using an auto-keratometer and axial eyeball length using A-scan ultrasonography. Results A total of 200 attendances were studied, 90 males and 110 females. All were emmetropic. The age range was 21-52 years, and the highest contributors were in the 21-30-year age group. The association between right axial length and right corneal curvature shows a negative relation among both sexes. It was -0.61 (β-coefficient (β-coff)), and highly significant in females at -0.89 (β-coff). Additionally, the association between left axial length and left corneal curvature shows a negative relation of -0.65 (β-coff), which was again highly significant in females at -0.87 (β-coff). Both were not significant in males. There was no significant association linking axial length and eye axis in both sexes. The multivariate regression model was used to assess the p-value, and the regression model was adjusted by age. Conclusion Optical parametric measurement is a noninvasive diagnostic and assessment tool that might help in the actual measurement of intraocular lens implantation in cataract surgery and may also provide supplementary information to the researcher domain.

New loci for refractive errors and ocular biometric parameters in young Chinese Han adults

Myopia has become a major public health issue with an increasing prevalence. There are still individuals who experience similar environmental risk factors and, yet, remain non-myopic. Thus, there might be genetic factors protecting people from myopia. Considering the opposite ocular characteristics of primary angle closure glaucoma (PACG) to myopia and possible common pathway between them, we propose that certain risk genes for PACG might act as a protective factor for myopia. In this study, 2,678 young adults were genotyped for 37 targeted single nucleotide polymorphisms. Compared with emmetropia, rs1401999 (allele C: OR=0.795, P=0.03; genotype in dominant model: OR=0.759, P=0.02) and rs1258267 (allele A: OR=0.824, P=0.03; genotype in dominant model: OR=0.603, P=0.01) were associated with low to moderate myopia and high myopia, respectively. Genotype under recessive model of rs11024102 was correlated with myopia (OR=1.456, P=0.01), low to moderate myopia (OR=1.443, P=0.02) and high myopia (OR=1.453, P=0.02). However, these associations did not survive Bonferroni correction. Moreover, rs1401999, rs1258267, and rs11024102 showed associations with certain ocular biometric parameters in different groups. Our study suggests that ABCC5, CHAT and PLEKHA7 might be associated with refractive errors by contributing to the regulation of ocular biometry, in terms of uncorrected results and their biological functions.

Deep learning for predicting uncorrected refractive error using posterior segment optical coherence tomography images

BACKGROUND/OBJECTIVES

This study aimed to evaluate a deep learning model for estimating uncorrected refractive error using posterior segment optical coherence tomography (OCT) images.

METHODS

In this retrospective study, we assigned healthy subjects to development (N = 688 eyes of 344 subjects) and test (N = 248 eyes of 124 subjects) datasets (prospective validation design). We developed and validated OCT-based deep learning models to estimate refractive error. A regression model based on a pretrained ResNet50 architecture was trained using horizontal OCT images to predict the spherical equivalent (SE). The performance of the deep learning model for detecting high myopia was also evaluated. A saliency map was generated using the Grad-CAM technique to visualize the characteristic features.

RESULTS

The developed model showed a low mean absolute error for SE prediction (2.66 D) and a significant Pearson correlation coefficient of 0.588 (P < 0.001) in the test dataset validation. To detect high myopia, the model yielded an area under the receiver operating characteristic curve of 0.813 (95% confidence interval [CI], 0.744-0.881) and an accuracy of 71.4% (95% CI, 65.3-76.9%). The inner retinal layers and relatively steepened curvatures were highlighted using a saliency map to detect high myopia.

CONCLUSION

A deep learning algorithm showed that OCT could potentially be used as an imaging modality to estimate refractive error. This method will facilitate the evaluation of refractive error to prevent clinicians from overlooking the risks associated with refractive error during OCT assessment.

Prevalence and Factors Associated with Optic Disc Tilt in the Primary Open-Angle African American Glaucoma Genetics Study

PURPOSE

To investigate the prevalence and factors associated with optic disc tilt in the eyes of Black Americans with glaucoma.

DESIGN

Cross-sectional.

PARTICIPANTS

Subjects with glaucoma participating in the Primary Open-Angle African American Glaucoma Genetics (POAAGG) study.

METHODS

Stereo pairs of optic disc images were assessed independently by POAAGG-certified nonphysician graders for quantitative features including maximum and minimum linear disc diameters, and qualitative features including gradeability of images, shape of the cup, rim plane position, β-peripapillary atrophy, sloping region adjacent to the outer disc margin, and rim pallor. Discrepancies were adjudicated by an ophthalmologist. Descriptive statistics and P values were generated for associations of tilt with demographic and ocular characteristics. Stepwise multivariable analysis was performed with logistic regression using Generalized Estimating Equations (GEEs) to account for inter-eye correlation within subjects.

MAIN OUTCOME MEASURES

Tilt Ovality Index (TOI) of >1.30 and Stereoscopically Identified optic disc Tilt (SIT).

RESULTS

Among 1251 subjects with data on both eyes, 104 (8.3%) had TOI. Subjects with TOI were less likely to be male (adjusted odds ratio [aOR], 0.46, 95% confidence interval [CI], 0.29-0.74, P < 0.001). Eyes with TOI were less likely to have large cup disc ratios (aOR, 0.18, 95% CI, 0.06-0.53, P < 0.001) and less likely to have cylinder-shaped cups compared with conical-shaped cups (aOR, 0.31, 95% CI, 0.19-0.49, P < 0.001). Among 1007 subjects with data on both eyes, 254 (25.2%) had SIT. Subjects with SIT were younger (aOR, 0.95, 95% CI, 0.93-0.96, P < 0.001), and eyes with SIT were more likely to have oval-shaped discs compared with round discs (aOR, 1.82, 95% CI, 1.32-2.52, P < 0.001), more likely to have a sloping region adjacent to the outer disc margin instead of being flat (aOR, 3.26, 95% CI, 2.32-4.59, P < 0.001), and less likely to have cylinder-shaped cups compared with conical-shaped cups (aOR, 0.59, 95% CI, 0.41-0.85, P < 0.001). Both TOI and SIT were not associated with myopia.

CONCLUSIONS

There are substantial numbers of tilted optic discs in glaucoma patients with African ancestry. They occur more frequently in female subjects and younger subjects and are associated with several ocular features but not with myopia.

Association Between Myopic Refractive Error and Primary Open-Angle Glaucoma: A 2-Sample Mendelian Randomization Study

Importance

Refractive error (RE) is the most common form of visual impairment, and myopic RE is associated with an increased risk of primary open-angle glaucoma (POAG). Whether this association represents a causal role of RE in the etiology of POAG remains unknown.

Objective

To evaluate shared genetic influences and investigate the association of myopic RE with the risk for POAG.

Design, Setting, and Participants

Observational analyses were used to evaluate the association between mean spherical equivalent (MSE) RE (continuous trait) or myopia (binary trait) and POAG risk in individuals from the Genetic Epidemiology Research on Adult Health and Aging (GERA) cohort. To quantify genetic overlap, genome-wide genetic correlation analyses were performed using genome-wide association studies (GWAS) of MSE RE or myopia and POAG from GERA. Potential causal effects were assessed between MSE RE and POAG using 2-sample Mendelian randomization. Genetic variants associated with MSE RE were derived using GWAS summary statistics from a GWAS of RE conducted in 102 117 UK Biobank participants. For POAG, we used GWAS summary statistics from our previous GWAS (3836 POAG cases and 48 065 controls from GERA). Data analyses occurred between July 2020 and October 2021.

Main Outcomes and Measure

Our main outcome was POAG risk as odds ratio (OR) caused by per-unit difference in MSE RE (in diopters).

Results

Our observational analyses included data for 54 755 non-Hispanic White individuals (31 926 [58%] females and 22 829 [42%] males). Among 4047 individuals with POAG, mean (SD) age was 73.64 (9.20) years; mean (SD) age of the 50 708 controls was 65.38 (12.24) years. Individuals with POAG had a lower refractive MSE and were more likely to have myopia or high myopia compared with the control participants (40.2% vs 34.1%, P = 1.31 × 10-11 for myopia; 8.5% vs 6.8%, P = .004 for high myopia). Our genetic correlation analyses demonstrated that POAG was genetically correlated with MSE RE (rg, -0.24; SE, 0.06; P = 3.90 × 10-5), myopia (rg, 0.21; SE, 0.07; P = .004), and high myopia (rg, 0.23; SE, 0.09; P = .01). Genetically assessed refractive MSE was negatively associated with POAG risk (inverse-variance weighted model: OR per diopter more hyperopic MSE = 0.94; 95% CI, 0.89-0.99; P = .01).

Conclusions and Relevance

These findings demonstrate a shared genetic basis and an association between myopic RE and POAG risk. This may support population POAG risk stratification and screening strategies, based on RE information.

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.

The iridocorneal angle and related anterior segment structures in pediatric anisohyperopic amblyopic eyes

Objectives:

We aimed at investigating the iridocorneal angle, anterior segment structural differences, and their relationship in pediatric anisohyperopic amblyopic eyes.

Methods:

This study was designed as an observational case-control study. We prospectively evaluated the pediatric patients who were newly diagnosed with hyperopic anisometropic amblyopia. Iridocorrneal angle in four sectors, axial length, and anterior segment structures were compared to emmetropic fellow and control eyes using Pentacam and IOLMaster 700 devices. The anisohyperopia and iridocorneal angle related factors were determined in hyperopic anisometropic amblyopic eyes.

Results:

Forty-three hyperopic anisometropic amblyopic eyes, 43 fellow eyes, and 44 control eyes were included. The mean axial length, anterior chamber volume, and anterior chamber depth were significantly reduced in the study eyes compared to the fellow (p < 0.001, p = 0.021, and p = 0.045, respectively) and control eyes (p < 0.001, p = 0.001, and p = 0.009, respectively). The average iridocorneal angle was significantly lower in the study eyes than in the fellow and control eyes (p < 0.001 and p = 0.018, respectively). The iridocorneal angle correlated with anterior chamber depth (r = 0.49, p = 0.013), anterior chamber volume (r = 0.42, p = 0.038), the anterior radius of curvature (r =−0.54, p = 0.005), the posterior radius of curvature (r =−0.58, p = 0.002), and lens thickness (Rho =−0.41, p = 0.033) in the study eyes. Anisohyperopia was related to the interocular difference in axial length (Rho = 0.53, p = 0.005), anterior chamber depth (Rho = 0.53, p = 0.005), and anterior chamber volume (Rho = 0.42, p = 0.031).

Conclusion:

Pentacam and IOLMaster 700 are suitable for non-contact imaging of iridocorneal angle and anterior segment structures in the pediatric age. These biometric differences and their relationship should be kept in mind whenever anterior or posterior segment surgery is planned for pediatric anisohyperopic amblyopic eyes.

Glaucoma diagnostic performance of macular ganglion cell complex thickness using regular and long axial length normative databases

The risks of misdiagnosing a healthy individual as glaucomatous or vice versa may be high in a population with a large majority of highly myopic individuals, due to considerable morphologic variability in high myopic fundus. This study aims to compare the diagnostic ability of the regular and long axial length databases in the RS-3000 Advance SD-OCT (Nidek) device to correctly diagnose glaucoma with high myopia. Patients with high myopia (axial length ≥ 26.0 mm) in Chang Gung Memorial Hospital, Taiwan between 2015 and 2020 were included. Glaucoma was diagnosed based on glaucomatous discs, visual field defects and corresponding retinal nerve fiber layer defects. The sensitivity, specificity, diagnostic accuracy and likelihood ratios of diagnosing glaucoma via mGCC thickness in both superior/inferior and GChart mapping using the regular and long axial length normative databases. The specificity and diagnostic accuracy of mGCC thickness for distinguishing glaucomatous eyes from nonglaucomatous eyes among highly myopic eyes were significantly improved using the long axial length database (p = 0.046). There were also significant proportion changes in S/I mapping as well as GChart mapping (37.3% and 48.0%, respectively; p < 0.01) from abnormal to normal in the myopic normal eye group when using the long axial length normative database. The study revealed that clinicians could utilize a long axial length database to effectively decrease the number of false-positive diagnoses or to correctly identify highly myopic normal eyes misdiagnosed as glaucomatous eyes.

Interaction of background genetic risk, psychotropic medications, and primary angle closure glaucoma in the UK Biobank

BACKGROUND/AIMS

Psychotropic medications have been reported as a risk factor for angle closure disease. However, the interaction between background genetic risk for primary angle closure glaucoma (PACG) and susceptibility to angle closure disease among psychotropic medication users has not been investigated. Here we demonstrate the utility of a genome-wide polygenic risk score (PRS) in identifying and risk-stratifying subjects with PACG and investigate the association between PACG genetic burden and exposure to psychotropic medications on prevalent angle closure.

METHODS

This analysis used the UK Biobank dataset, a prospective cohort study of 502,506 UK residents. We constructed a PACG PRS for participants using genome-wide association study summary statistics from a multiethnic meta-analysis using the Lassosum method.

RESULTS

Among the 441,054 participants, 959 (0.22%) were identified as PACG cases. Individuals with PACG had higher PRS compared to those without PACG (0.24±1.03 SD vs. 0.00±1.00 SD, p<0.001) and PACG prevalence increased with each decile of higher PRS. Among individuals using psychotropic medication, those with PACG had higher average PRS (0.31±1.00 SD vs. 0.00±1.00 SD, p<0.001) and were more likely to have a PRS in upper deciles of polygenic risk (p = 0.04). At each decile of PRS, psychotropic medication use was associated with increased risk of PACG. These effects were more pronounced and significant in higher deciles.

CONCLUSION

We demonstrate the utility of a PRS for identifying individuals at higher risk of PACG. Additionally, we demonstrate an important relationship where the association between psychotropic medications use and PACG diagnosis varies across the polygenic risk spectrum.

Three-Dimensional Multi-Task Deep Learning Model to Detect Glaucomatous Optic Neuropathy and Myopic Features From Optical Coherence Tomography Scans: A Retrospective Multi-Centre Study

Purpose

We aim to develop a multi-task three-dimensional (3D) deep learning (DL) model to detect glaucomatous optic neuropathy (GON) and myopic features (MF) simultaneously from spectral-domain optical coherence tomography (SDOCT) volumetric scans.

Methods

Each volumetric scan was labelled as GON according to the criteria of retinal nerve fibre layer (RNFL) thinning, with a structural defect that correlated in position with the visual field defect (i.e., reference standard). MF were graded by the SDOCT en face images, defined as presence of peripapillary atrophy (PPA), optic disc tilting, or fundus tessellation. The multi-task DL model was developed by ResNet with output of Yes/No GON and Yes/No MF. SDOCT scans were collected in a tertiary eye hospital (Hong Kong SAR, China) for training (80%), tuning (10%), and internal validation (10%). External testing was performed on five independent datasets from eye centres in Hong Kong, the United States, and Singapore, respectively. For GON detection, we compared the model to the average RNFL thickness measurement generated from the SDOCT device. To investigate whether MF can affect the model’s performance on GON detection, we conducted subgroup analyses in groups stratified by Yes/No MF. The area under the receiver operating characteristic curve (AUROC), sensitivity, specificity, and accuracy were reported.

Results

A total of 8,151 SDOCT volumetric scans from 3,609 eyes were collected. For detecting GON, in the internal validation, the proposed 3D model had significantly higher AUROC (0.949 vs. 0.913, p &lt; 0.001) than average RNFL thickness in discriminating GON from normal. In the external testing, the two approaches had comparable performance. In the subgroup analysis, the multi-task DL model performed significantly better in the group of “no MF” (0.883 vs. 0.965, p-value &lt; 0.001) in one external testing dataset, but no significant difference in internal validation and other external testing datasets. The multi-task DL model’s performance to detect MF was also generalizable in all datasets, with the AUROC values ranging from 0.855 to 0.896.

Conclusion

The proposed multi-task 3D DL model demonstrated high generalizability in all the datasets and the presence of MF did not affect the accuracy of GON detection generally.

Genetic analysis assists diagnosis of clinical systemic disease in children with excessive hyperopia

BACKGROUND

A thorough examination (especially those including visual functional evaluation) is very important in children's eye-development during clinical practice, when they encountered with unusual excessive hyperopia especially accompanied with other possible complications. Genetic testing would be beneficial for early differential diagnosis as blood sampling is more convenient than all other structural imaging capture tests or functional tests which need children to cooperate well. Thus genetic testing helps us to filter other possible multi-systemic diseases in children patients with eye disorder.

CASE PRESENTATION

A 3-year-old and an 8-year-old boy, both Chinese children clinically manifested as bilateral excessive hyperopia (≥+10.00), severe amblyopia and exotropia, have been genetically diagnosed as Senior-Loken syndrome-5 (SLSN5) and isolated posterior microphthalmos (MCOP6), respectively.

CONCLUSIONS

This report demonstrates the importance of genetic diagnosis before a clinical consult. When children are too young to cooperate with examinations, genetic testing is valuable for predicting other systemic diseases and eye-related development and for implementing early interventions for the disease.

Glaucoma diagnosis using multi-feature analysis and a deep learning technique

In this study, we aimed to facilitate the current diagnostic assessment of glaucoma by analyzing multiple features and introducing a new cross-sectional optic nerve head (ONH) feature from optical coherence tomography (OCT) images. The data (n = 100 for both glaucoma and control) were collected based on structural, functional, demographic and risk factors. The features were statistically analyzed, and the most significant four features were used to train machine learning (ML) algorithms. Two ML algorithms: deep learning (DL) and logistic regression (LR) were compared in terms of the classification accuracy for automated glaucoma detection. The performance of the ML models was evaluated on unseen test data, n = 55. An image segmentation pilot study was then performed on cross-sectional OCT scans. The ONH cup area was extracted, analyzed, and a new DL model was trained for glaucoma prediction. The DL model was estimated using five-fold cross-validation and compared with two pre-trained models. The DL model trained from the optimal features achieved significantly higher diagnostic performance (area under the receiver operating characteristic curve (AUC) 0.98 and accuracy of 97% on validation data and 96% on test data) compared to previous studies for automated glaucoma detection. The second DL model used in the pilot study also showed promising outcomes (AUC 0.99 and accuracy of 98.6%) to detect glaucoma compared to two pre-trained models. In combination, the result of the two studies strongly suggests the four features and the cross-sectional ONH cup area trained using deep learning have a great potential for use as an initial screening tool for glaucoma which will assist clinicians in making a precise decision.

Degree of Myopia and Glaucoma Risk: A Dose-Response Meta-analysis

PURPOSE

To verify the dose-response relation between the degree of myopia and open-angle glaucoma (OAG) risk DESIGN: Dose-response meta-analysis.

METHODS

We searched the PubMed, EMBASE, and Cochrane Library databases for population-based studies published until November 30, 2020, and reporting on both myopia and OAG. Random-effect models generated pooled odds ratios (OR) and 95% CIs. Results robustness was confirmed by influence and subgroup analyses. A 2-stage dose-response meta-analysis calculated the OAG risk per unit dose of myopia (spherical equivalent [SE] decrease of 1 diopter [D]) and examined the relationship pattern.

RESULTS

The meta-analysis comprised 24 studies in 11 countries (514,265 individuals). The pooled OR of any myopia degree's association with OAG was 1.88 (95% CI, 1.66-2.13; I² = 53%). The OR differences based on ethnicity (Asians vs Westerners) or 5 geographic areas were not statistically significant (P = .80 and P = .06, respectively). The pooled ORs of the associations between low, moderate, moderate-to-high, high myopia, and OAG were 1.50 (95% CI, 1.29-1.76), 1.69 (95% CI, 1.33-2.15), 2.27 (95% CI, 1.74-2.96), and 4.14 (95% CI, 2.57-6.69), respectively. According to the dose-response meta-analysis, the pooled OR (per SE 1-D change) was 1.21 (95% CI, 1.15-1.28). The OAG risk accelerated at approximately -6 D, and further accelerated from -8 D, showing a nonlinear concave upward slope (P = .03).

CONCLUSIONS

For each unit (1-D) increase in myopia, the risk of glaucoma increases by approximately 20%. The risk more steeply increases in high-degree myopia, representing a significant nonlinear relationship.