Is high myopia a risk factor for visual field progression or disk hemorrhage in primary open-angle glaucoma?

Clinical Characteristics and Associated Factors to the Development of Glaucoma in Eyes With Myopic Optic Neuropathy

PURPOSE

To observe the development of glaucoma in myopic eyes with and without myopic optic neuropathy (MON) and analyze associated factors to the development of typical glaucomatous damage.

DESIGN

A prospective, observational, cohort study.

METHODS

A total of 233 myopic eyes with no definite evidence of glaucomatous damage were included. Myopic patients without any retinal nerve fiber layer (RNFL) or visual field (VF) abnormalities were classified as myopic eyes without MON. Myopic patients with decreased RNFL at the superonasal (SN) or nasal area, and with corresponding VF defects either in the temporal or inferotemporal (IT) region were classified as myopic eyes with MON. Myopic eyes that developed glaucoma were defined by the presence of glaucomatous VF in the SN region including defects in Bjerrum area, or a new localized RNFL defect in the IT region. Disc morphological features and optic nerve head (ONH) parameters of two groups were compared.

RESULTS

Myopic eyes with MON had a thinner average peripapillary RNFL thickness (P < 0.001), worse MD of the VF (P = 0.031), a higher percentage of IT VF defects (P < 0.001), smaller torsion degree (P = 0.047), and greater LCD (P = 0.022). Myopic eyes with MON who developed glaucoma had a thinner average peripapillary RNFL thickness (P = 0.009), greater PPA area (P = 0.049), greater LCD (P < 0.001), and thinner LCT (P < 0.001). Thinner baseline temporal RNFL thickness (HR, 0.956; 95% CI, 0.928-0.986; P = 0.004), greater baseline LCD (HR, 1.003; 95% CI, 1.000-1.005; P = 0.022), and greater PPA area (HR, 1.000; 95% CI, 1.000-1.003; P = 0.050) were significantly associated factors with glaucoma development.

CONCLUSIONS

Myopic eyes with MON have a greater risk to develop glaucoma compared to myopic eyes without MON. Structural weakness due to myopia, especially at the temporal side of the ONH and the peripapillary sclera, increases the risk of glaucoma in myopic eyes with MON.

Optic Nerve Head Curvature Flattening Is Associated with Central Visual Field Scotoma

This study aimed to develop a new index, the average curvature ratio (ACR), to represent the optic nerve head (ONH) tilting and investigate its clinical relevance. Myopic eyes were included and divided into two subgroups: flat ONH (ACR < 1.0) and convex ONH (ACR ≥ 1.0). The occurrences of central and peripheral visual field (VF) defects were compared between the two groups. A total of 375 myopic eyes were recruited, and 231 and 144 eyes were included in the flat and convex ONH groups, respectively. Central scotoma occurred more frequently in the flat ONH group. According to the Patella-Anderson criteria, the number of eyes with central scotoma was 103 (44.6%) in the flat and 44 (30.6%) in the convex ONH groups (p = 0.009). According to Kook's criteria, the number of eyes with central scotoma was 122 (52.8%) in the flat and 50 (34.7%) in the convex ONH groups (p < 0.001). Peripheral scotoma was not significantly different between the groups. In the correlation analysis, the ACR was positively correlated with spherical equivalence, but not with axial length or central corneal thickness. The ACR reflects the degree of the ONH tilt and is a good index for estimating central VF damage in myopic eyes.

The Association between Myopia and Primary Open-Angle Glaucoma: A Systematic Review and Meta-Analysis

BACKGROUND

Previous studies identified myopia as a risk factor for primary open-angle glaucoma (POAG). However, recent studies have shown different results, the definitive relationship between myopia and POAG remains controversial.

OBJECTIVES

To investigate the relationship between myopia and POAG.

METHODS

Published articles were searched from PubMed, Embase, and Scopus databases between 1970 and 2020. A pooled analysis of the ORs was performed using a random-effects model.

RESULTS

Data on the association between myopia and POAG, were obtained from 16 cross sectional studies, and the pooled OR was 2.26 (95% confidence interval [CI], 1.77 - 2.89, P < 0.001) in random effects model (I2 = 86%; P < 0.01). For the relationship of myopia and POAG progression, data from seven longitudinal cohort studies were included and the pooled OR was 0.85 (95% CI, 0.73 - 0.99, P = 0.042) in the random-effects model (I2 = 88%; P < 0.01).

CONCLUSION

Our findings demonstrated that myopia may be a risk factor associated with POAG and a possible protective factor for POAG progression. It may due to myopia with the presence of a lamina cribrosa defect slow down the visual field loss also POAG progression, further research for underlying mechanisms is still needed.

Characteristics of progressive temporal visual field defects in patients with myopia

Temporal visual field damage (VFD) is the common type of non-glaucomatous VF defects found in eyes with myopia. However, little is known about the factors associated with its progression. We investigated the characteristic of myopic eyes with progressive temporal VF defects. This retrospective, observational study included a total of 116 eyes: 39 eyes with temporal VFDs and an axial length greater than 24.5 mm, 77 eyes with typical glaucomatous VFDs who were followed up more than 5 years. VF progression was evaluated with Trend-based global progression analysis. In the temporal VFD group, the greater tilt ratios, the higher prevalence of β-zone peripapillary atrophy (β-PPA), the substantial increase in β-PPA were found, compared to the typical glaucomatous VFD groups (all P-values ≤ 0.001). The temporal VFD group had the slower progression than the typical glaucomatous VFD group on trend-based GPA (P = 0.047). In the multivariate linear regression analysis, the change of β-PPA area over years was related to temporal VFD progression (B, − 0.000088, P = 0.003). In conclusion, myopic eyes with the temporal VFD, which come with growing β-PPA area, should be monitored with extra caution.

Angular Location of Retinal Nerve Fiber Layer Defect: Association With Myopia and Open-Angle Glaucoma

Purpose

To compare retinal nerve fiber layer (RNFL) defects' angle measurements determined from the center of the optic disc and Bruch's membrane opening (BMO), as a function of myopia and open-angle glaucoma (OAG) subtypes.

Methods

In total, 118 patients with OAG were grouped by axial length (AL; high myopia, AL >26 mm; mild to moderate myopia, 24 ≤ AL ≤26 mm; nonmyopia, AL <24 mm) and OAG subtype (normal-tension glaucoma [NTG], high-tension glaucoma [HTG]). The disc and BMO centers were determined by a merged image of red-free fundus photography and spectral-domain optical coherence tomography. The angular location of the RNFL defect close to the fovea (angle α) was measured from the disc center and BMO center, respectively (angle αdisc and angle αBMO). The difference between angle αdisc and αBMO (Δα), as well as the RNFL defect width (angle γ), was evaluated.

Results

Angle αdisc was smaller in myopic eyes and correlated significantly with AL (P = 0.001), whereas it did not differ among OAG subgroups. Angle αBMO and angle γ were not different in the myopic and OAG subgroups. The Δ α was larger for eyes with higher degree of myopia and had significant correlation with AL (P < 0.001) and was larger in NTG eyes than in HTG eyes (P = 0.023).

Conclusions

The angular location of the RNFL defect measured from the disc center, but not from the BMO center, was closer to the fovea for glaucomatous eyes with higher values of AL. The present study may facilitate understanding of the characteristic locational pattern of the RNFL defect in myopic glaucomatous eyes.

Longitudinal Macular Ganglion Cell-Inner Plexiform Layer Measurements to Detect Glaucoma Progression in High Myopia

PURPOSE

To investigate whether progressive macular ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (RNFL) thinning are predictive for detecting visual field (VF) progression in eyes with high myopia.

DESIGN

Cohort study.

METHODS

A total of 104 primary open-angle glaucoma (POAG) eyes with high myopia and 104 age- and VF severity-matched POAG eyes without high myopia (mean follow-up, 5.4 years) were included. High myopia was defined as a spherical equivalent <-6.0 diopters or axial length >26.5 mm. Progressive GCIPL, RNFL, and VF deterioration were determined by Guided Progression Analysis (GPA) in optical coherence tomography and standard automated perimetry. The risk of VF progression was evaluated using Cox proportional hazard models.

RESULTS

Highly myopic eyes with progressive GCIPL thinning had a significantly higher risk of developing VF progression after adjusting for the baseline intraocular pressure (HR 4.00; P = .001) or peak intraocular pressure (HR 3.11; P = .011) in the multivariable Cox proportional hazard model, whereas highly myopic eyes with progressive RNFL thinning were not significantly associated with VF progression. In eyes without high myopia, both progressive GCIPL (HR 4.67 or 3.62; P = .008 or .037, respectively) and RNFL (HR 6.60 or 3.97; P = .001 or .016, respectively) thinning were associated with a significantly higher risk of developing VF progression after adjusting for the baseline or peak intraocular pressure.

CONCLUSIONS

Monitoring macular GCIPL thickness was effective for predicting glaucoma progression regardless of the presence of high myopia.

Association between corneal refractive surgery and the prevalence of glaucoma: Korea National Health and Nutrition Examination Survey 2010-2012

AIM

To determine the relationship between corneal refractive surgery and the prevalence of glaucoma in the Korean population.

METHODS

Data were obtained from the Korea National Health and Nutrition Examination Survey (KNHANES), a population-based cross-sectional study using a complex, stratified, multistage, probability-cluster survey. This study included 604 eyes that had undergone myopic corneal refractive surgery, and 3389 control eyes without a history of any ocular surgery and having a spherical equivalent (SE) <-3.00 D, obtained from the KNHANES database for the years 2010-2012. Glaucoma diagnosis was based on the International Society of Geographical and Epidemiological Ophthalmology criteria. The association between a history of corneal refractive surgery and the prevalence of glaucoma was analysed using logistic regression analysis, after adjusting for potential confounding factors.

RESULTS

Glaucoma prevalence did not differ between eyes that had and had not undergone corneal refractive surgery (p=0.675). After adjusting for age, sex, SE, and intraocular pressure, multivariate logistic regression analysis found that corneal refractive surgery was significantly associated with an increased risk of glaucoma (OR 9.14, p=0.002; 95% CI 2.22 to 37.69). Subgroup analysis that only included control eyes with a refraction cut-off <-3.70 D found that corneal refractive surgery was not significantly associated with glaucoma.

CONCLUSIONS

History of corneal refractive surgery was associated with a higher prevalence of glaucoma in the Korean population. However, this association was not observed in eyes with a higher degree of myopia.

Posterior scleral deformation and autonomic dysfunction in normal tension glaucoma

In meta-analyses, it has been reported that myopia is a risk factor for glaucoma and there is increasing evidence that autonomic dysfunction causing vascular dysregulation or perfusion dysfunction is considered an important factor in the progression of glaucoma. There have been experimental studies to find out the association between autonomic nervous system and ocular growth, but no clinical study yet has evaluated the relationship between them. Therefore, we enrolled 208 open angle glaucoma patients and measured heart-rate-variability(HRV). We used the standard deviation value of the qualified normal to normal intervals (SDNN) parameter of HRV, which is considered an autonomic influence index and characterized the total effect of the regulation of autonomic blood circulation. Patients were classified into the two groups according to SDNN: those with low possibility of autonomic dysfunction (LoAD group) and those with high possibility of autonomic dysfunction (HiAD group). We evaluated myopic features employing a 'posterior scleral profile' identified by the disc tilt ratio, disc torsion, fovea-BMO center (FoBMO) angle and peripapapillary area(PPA) to disc ratio. HiAD group showed higher values than LoAD group in posterior scleral deformation profile such like axial length, disc tilt, torsion degree. We suggest the possibility of association between myopic deformation and autonomic dysfunction.

Morphological prediction of glaucoma by quantitative analyses of ocular shape and volume using 3-dimensional T2-weighted MR images

Elongated axial length of the eye increases the morbidity of glaucoma. Myopia also associates with elongated axial length, and such ellipsoid shape of the eyeball strongly contributes its pathogenesis. Morphological features of the eyeballs, which could be important factors for developing glaucoma, have not been well described. The aim of this study was to investigate the three-dimensional (3D) topographic features of glaucomatous eyeballs with/without myopia to evaluate the potential of those features for predicting glaucoma. Using a 3.0-tesla MRI, volume-isotropic turbo-spin-echo acquisition T2-weighted images were obtained from 55 patients with glaucoma and 22 controls to delineate the eyeballs. Eyeball volumes, axial lengths and transverse lengths were semi-automatically calculated and compared between four groups: normal, myopia, glaucoma, and glaucoma with myopia. Both glaucoma and myopia increased the eyeball volume compared to the normal eyes. An increased anisotropy ratio (axial/transversus length) was observed in myopic eyes compared to normal, whereas in the glaucomatous eyes, with or without myopia, no increase in anisotropy ratio was observed. Increasing volume of eyes can be caused by myopia and glaucoma. Myopic eyes were ellipsoid in shape, but there was less anisotropy and a near-spherical shape in glaucomatous eyes, even in glaucomatous myopic eyes.

Posterior scleral deformations around optic disc are associated with visual field damage in open-angle glaucoma patients with myopia

Purpose

To identify important variables associated with visual field (VF) defects in open-angle glaucoma (OAG) with myopia.

Materials and methods

A total of 105 OAG with myopia were enrolled in this cross-sectional study. The disc tilt ratio, disc torsion degree, disc-foveal angle, and area of peripapillary atrophy (PPA) were measured from red-free fundus photographs. Patients underwent Swept-source optical coherence tomography to measure peripapillary retinal nerve fiber layer (RNFL), subfoveal choroidal, and sufoveal scleral thicknesses. Functional evaluation was performed using 24–2 standard automated perimetry. For statistical analyses, logistic regression, artificial neural networks (ANN), and hierarchical cluster analysis were performed.

Results

Logistic regression demonstrated peripapillary RNFL thickness as a significant variable for the presence of VF defects, otherwise ANN identified PPA area, peripapillary RNFL thickness, disc-foveal angle, and disc torsion degree as significant clinical variables in OAG with myopia. Two clusters were made after a hierarchical cluster analysis. Cluster 2 showed significantly worse VF damage than cluster 1 (MD = -5.20±5.25 dB for cluster 2 and -1.84±3.02 dB for cluster 1, P < .001). Cluster 2 had significantly greater disc tilt ratio, disc-foveal angle, and PPA area compared with cluster 1 (P < .001, 0.005, and < .001, respectively).

Conclusions

Generally peripapillary RNFL thickness is considered as an important variable associated with visual field defects in glaucoma patients. ANN identified parameters associated with posterior scleral deformations around optic disc induced by myopic change including PPA area, disc torsion degree, and disc-foveal angle as significant clinical variables for visual field damage in OAG with myopia.

Prevalence of Normal-Tension Glaucoma in the Chinese Population: A Systematic Review and Meta-Analysis

PURPOSE

To investigate the prevalence of normal-tension glaucoma (NTG) in the Chinese population through systematic review and meta-analysis.

DESIGN

Systematic review and meta-analysis.

METHODS

All Chinese population-based studies that reported the prevalence of NTG were identified. We searched PubMed and Chinese databases including Wanfang, China National Knowledge Infrastructure, and VIP for studies published before December 31, 2017. Random effects meta-analysis was conducted to estimate the pooled prevalence of NTG.

RESULTS

Twelve studies were included in this review and meta-analysis, including 9 population-based studies and 3 studies from glaucoma clinics and managed care networks. The 9 population-based studies included a total of 30,892 subjects with 498 patients with primary open-angle glaucoma (POAG) and 354 patients with NTG. The prevalence of estimated NTG ranged from 0.36% to 1.98% and the percentage of NTG among POAG ranged from 51.43% to 83.58%. In the glaucoma clinic and managed care network studies, NTG prevalence was much lower. The overall pooled proportion of NTG among POAG in the Chinese population was 70.0% (95% confidence interval [CI] 62.0-77.0%). The overall pooled prevalence of POAG and NTG was 2.0% (95% CI 1.0-2.0%) and 1.0% (95% CI 1.0-1.0%), respectively. For the meta-regression of the NTG/POAG proportion, we found that age, gender, intraocular pressure, and China versus not China were not significantly associated with NTG/POAG prevalence, although the proportional prevalence decreased with increasing age category.

CONCLUSIONS

In this systematic review, we found that NTG is common among patients with POAG in the Chinese population. Our findings can help guide future glaucoma studies and public health guidelines in the Chinese population.

The impact of disc hemorrhage studies on our understanding of glaucoma: a systematic review 50 years after the rediscovery of disc hemorrhage

PURPOSE OF REVIEW

To trace the influence of disc hemorrhage studies on our understanding of glaucoma.

SOURCES

Major articles published during the last 50 years since the rediscovery of disc hemorrhage were identified. A total of 196 articles were selected from 435 articles retrieved using the keywords glaucoma and disc hemorrhage as of August 9 2018 from PubMed.

RECENT FINDINGS

The main characteristics of disc hemorrhage, including its morphology, recurrence rate, duration, increased incidence in glaucoma, and role in the progression of normal tension glaucoma was well understood by the year 2000. Since then, studies have focused on more sophisticated and accurate methods of elucidating both structural and functional progression, with special attention to the role of the lamina cribrosa. Nevertheless, both the mechanism of disc hemorrhage development and its fuller relationship with glaucoma remain unclear. Disc hemorrhage research requires careful study of glaucomatous optic neuropathy. This has been facilitated by recent advances in optical coherence tomography (OCT) angiography and other OCT technologies. Furthermore, animal studies of disc hemorrhage promise new insights into glaucomatous optic neuropathy.

MiR-93-5p targeting PTEN regulates the NMDA-induced autophagy of retinal ganglion cells via AKT/mTOR pathway in glaucoma

BACKGROUND

Glaucoma is hallmarked with the death of retinal neurons in the ganglion cell layer, which results in irreversible vision loss. The abnormal levels of miRNA have been associated with glaucoma. Our study purposed to explore the underlying molecule mechanism of miR-93-5p in NMDA-induced glaucoma.

METHODS

The Sprague-Dawley (SD) rats were used for the establishment of glaucoma model with the injection of NMDA. Vision behavior test were performed on the glaucoma rats. MiR-93-5p expression was determined by real-time PCR. The levels of autophagy-related protein and PTEN were assessed by Western blot assays. TUNEL assay and flow cytometry were performed to analyze cell apoptosis in vivo and in vitro, respectively. And cell viability was examined by CKK-8 assay. The relationship between miR-93-5p and PTEN was confirmed by Dual-Luciferase reporter gene system.

RESULTS

NMDA-induced glaucoma rats exhibited less time in the dark box, suggesting the recession of their vision. Moreover, the retinal ganglion cell (RGC) viability was reduced not only in the glaucoma rat models but also in the glaucoma RGC models. The autophagy-related protein was obviously increased in the NMDA-treated rats or RGCs. PTEN regulated the autophagy of RGCs through AKT/mTOR pathway in NMDA-treated RGCs. MiR-93-5p could target regulate PTEN negatively, and exhibit the similar effect of 3-MA on the survival of RGCs.

CONCLUSION

Up-regulation of miR-93-5p binding with PTEN suppressed the autophagy of RGCs through AKT/mTOR pathway in NMDA-induced glaucoma.