Predicting the development of normal tension glaucoma and related risk factors in normal tension glaucoma suspects

An Electronic Frailty Index Based on Deficit Accumulation May Predict Glaucomatous Visual Field Progression

Purpose

To investigate whether an electronic frailty index (eFI) is associated with visual field loss in glaucoma.

Patients and Methods

We identified 1163 subjects ≥65 years old with glaucoma (1082 right eyes and 1042 left eyes) who had a calculable baseline eFI, and who had reliable visual fields at baseline and final follow-up. Multivariable linear regression models adjusting for demographic and clinical variables were used to assess the association between eFI and mean deviation at baseline and the change in mean deviation over time in each eye.

Results

Being pre-frail or frail was not associated with baseline MD, except in the right eye where being pre-frail was associated with a higher baseline MD. Increasing level of eFI was negatively correlated with change in MD (p<0.05 both eyes), but not baseline MD. Moreover, being frail was significantly associated with a more significant decline in MD in both eyes (Right eye: Beta -0.89, 95% CI (-1.71, -0.063), p=0.035; Left eye: Beta -1.25, 95% CI (-2.17, -0.34), p=0.007). Notably, baseline IOP was not associated with MD at baseline or the change in MD in the multivariable models.

Conclusion

Glaucoma patients who are frail may be at higher risk of experiencing visual field decline, independent of baseline IOP. Future studies should investigate whether interventions to improve frailty can decrease risk of glaucoma progression.

Glaucoma Progression in Treatment-Naïve Patients With Normal Tension Glaucoma With Myopia-Role of Intraocular Pressure

PRCIS

While myopia has been recognized as a positive prognostic factor for normal tension glaucoma (NTG) progression in the adult population, some myopic NTG eyes exhibited significant progression within 2 years when left untreated, even under low intraocular pressure (IOP).

OBJECTIVE

To determine the natural history and risk factors associated with progressive retinal nerve fiber layer (RNFL) thinning in previously stable, treatment-naïve, patients with NTG with myopia.

METHODS

This study included 111 myopic NTG eyes without IOP-lowering treatment for at least 1 year and without disease progression during the treatment-free period. The RNFL thickness was measured, and a visual field test was performed every 6-12 months for >2 years. Patients with progressive changes were classified as the P(+) group, whereas those without progression were classified as the P(-) group. Cox proportional hazards model assessed risk factors of progression, whereas linear regression determined factors associated with the rate of RNFL thinning.

RESULTS

Progressive change was observed in 25 of the 111 participants [P(+) group, 22.5%]. A family history of glaucoma, higher mean IOP, and maximum IOP during the follow-up were significant factors both for being in the P(+) group and for a faster RNFL thinning. None with a mean IOP <11 mm Hg were in the P(+) group. Davies test identified that 14.2 mm Hg was a significant breakpoint ( P = 0.042), above which the rate of RNFL thinning increased significantly with the mean IOP ( R2 = 0.252, P = 0.034).

CONCLUSIONS

Patients with myopic NTG untreated for IOP, especially those with a family history of glaucoma or higher IOP, are at increased risk of progression. Early treatment initiation is advised for high-risk patients with myopic NTG, even when their condition appears stable.

Nationwide cohort study of primary open angle glaucoma risk and cardiovascular factors among in Korean glaucoma suspects

This retrospective study investigated the risk of primary open-angle glaucoma (POAG) among individuals identified as glaucoma suspects and examined associated cardiovascular risk factors. We conducted a longitudinal, nationwide cohort study using data from the Korean National Health Insurance Service (KNHIS) and included 362,285 participants aged ≥ 40 years from the Korean National Health Screening Program (NHSP) without pre-existing POAG in 2009 and 2010. Of these, glaucoma suspects (n = 32,220) were defined as individuals with at least two recorded instances of the KCD code H400 for glaucoma suspect and no prior antiglaucoma medication prescriptions before health screening. The primary outcome was the diagnosis of POAG and the prescription of antiglaucoma medications. Over a 6-year follow-up, 4.92% of glaucoma suspects developed POAG. Through multivariate Cox regression analysis, glaucoma suspects with diabetes, hypertension, dyslipidemia, or coronary heart disease exhibited a greater risk of conversion to POAG than those without these comorbidities ([HR, 1.354; 95%CI, 1.201 to 1.527] for diabetes, [HR, 1.139; 95%CI, 1.019 to 1.273] for systemic hypertension, [HR, 1.128; 95%CI, 1.013 to 1.26] for dyslipidemia, [HR, 1.124, 95%CI, 1.007 to 1.254] for coronary heart disease).This nationwide study observed that among glaucoma suspects, having cardiovascular risk factors/disease was associated with higher risk of developing POAG.

Implications of optic disc rotation in the visual field progression of myopic open-angle glaucoma

PURPOSE

To investigate the relationship between the characteristics of optic disc rotation and visual field (VF) progression in patients with myopic open-angle glaucoma (OAG).

METHODS

We included 53 eyes from 53 myopic OAG patients who were followed-up over a 3-year period. The characteristics of optic disc rotation including the degree of optic disc rotation, direction of optic disc rotation, and optic disc rotation-VF defect correspondence were investigated. The rates of global and regional VF progression were compared with different characteristics of optic disc rotation.

RESULTS

Thirty-seven eyes (69.8%) showed inferior optic disc rotation and 41 (77.4%) eyes showed optic disc rotation-VF defect correspondence. The inferiorly rotated optic discs with corresponding superior VF defect had faster VF progression in the superior peripheral region (P = 0.028) and superiorly rotated optic discs with corresponding inferior VF defect had faster VF progression in the inferior peripheral region (P = 0.031). The VF progression was restricted to the superior hemifield in the eyes with inferiorly rotated optic discs and corresponding superior VF defects.

CONCLUSION

In myopic OAG patients, the direction of optic disc rotation might predict faster VF progression in the corresponding peripheral region.

Age related cerebrospinal fluid flow dynamics in the subarachnoid space of the optic nerve in patients with normal tension glaucoma, measured by diffusion weighted MRI

BACKGROUND/OBJECTIVES

We aimed to measure cerebrospinal fluid (CSF) flow rates in the subarachnoid space (SAS) of the optic nerve (ON) by applying non-invasive diffusion-weighted MRI in patients with normal tension glaucoma (NTG) compared to age-matched controls.

SUBJECTS/METHODS

In this prospective study, an analysis of diffusion-weighted images of 26 patients with NTG (49ONs) and age-matched volunteers (52ONs) was conducted. Subjects were classified into 4 groups: group I (50-59 y., n = 12 eyes), group II (60-69 y., n = 16 eyes), group III (70-79 y., n = 18 eyes) and group IV ( > 80 y., n = 6 eyes) for NTGs and healthy volunteers, respectively. The flow-range ratio (FRR) between the frontal lobe SAS and the SAS of the ON was calculated for each age category group and then compared between age-categories as well as between NTGs and controls.

RESULTS

The mean FRR for age groups were (I) 0.54 ± 0.06 and 0.62 ± 0.03 (p < 0.05), (II) 0.56 ± 0.08 and 0.63 ± 0.03 (p < 0.05), (III) 0.54 ± 0.06 and 0.62 ± 0.02 (p < 0.001) as well as (IV) 0.61 ± 0.03 and 0.61 ± 0.04, for NTGs and controls, respectively. Using pooled data, the difference between the FRR in NTGs and controls was statistically significant (p < 0.0001). There were no statistically significant differences within the age categories of the control group. When comparing the FRR of NTGs by age categories, no statistically significant difference was found between the subgroups.

CONCLUSIONS

FRR was significantly reduced in NTGs compared to age-matched controls without any significant differences within the age groups themselves. Given the physiological importance of CSF for the integrity of neurons, axons and glial cells, reduced CSF flow dynamics might be part of the underlying neurodegenerative process of NTG.

Features Associated with Visible Lamina Cribrosa Pores in Individuals of African Ancestry with Glaucoma: Primary Open-Angle African Ancestry Glaucoma Genetics (POAAGG) Study

There are scarce data regarding the rate of the occurrence of primary open-angle glaucoma (POAG) and visible lamina cribrosa pores (LCPs) in the eyes of individuals with African ancestry; the potential impact of these features on disease burden remains unknown. We recruited subjects with POAG to the Primary Open-Angle African American Glaucoma Genetics (POAAGG) study. Through regression models, we evaluated the association between the presence of LCPs and various phenotypic features. In a multivariable analysis of 1187 glaucomatous eyes, LCPs were found to be more likely to be present in eyes with cup-to-disc ratios (CDR) of ≥0.9 (adjusted risk ratio (aRR) 1.11, 95%CI: 1.04-1.19, p = 0.005), eyes with cylindrical-shaped (aRR 1.22, 95%CI: 1.11-1.33) and bean pot (aRR 1.24, 95%CI: 1.13-1.36) cups versus conical cups (p < 0.0001), moderate cup depth (aRR 1.24, 95%CI: 1.06-1.46) and deep cups (aRR 1.27, 95%CI: 1.07-1.50) compared to shallow cups (p = 0.01), and the nasalization of central retinal vessels (aRR 1.33, 95%CI: 1.23-1.44), p < 0.0001). Eyes with LCPs were more likely to have a higher degree of African ancestry (q0), determined by means of SNP analysis (aRR 0.96, 95%CI: 0.93-0.99, p = 0.005 for per 0.1 increase in q0). Our large cohort of POAG cases of people with African ancestry showed that LCPs may be an important risk factor in identifying severe disease, potentially warranting closer monitoring by physicians.

Longitudinal Assessment of Retinal Nerve Fiber Layer and Ganglion Cell Complex Thicknesses in Patients With Large Optic Disc Cups and Normal Intraocular Pressure and Visual Fields

PRCIS

The thicknesses of the circumpapillary retinal nerve fiber layer (cpRNFL) and ganglion cell complex (GCC) did not change during 5 years in physiological large disc cupping.

PURPOSE

We evaluated longitudinal changes in the thicknesses of the cpRNFL and GCC in large disc cupping with a normal intraocular pressure (IOP) (<21 mm Hg) and visual field.

METHODS

This retrospective, consecutive case series study included 269 eyes of 269 patients with large disc cupping and normal IOP. We analyzed patient demographics, IOP, central corneal thickness, vertical cup-to-disc ratios using color fundus photography, the thicknesses of the cpRNFL and GCC using RTVue-100, and mean deviation using visual field examinations.

RESULTS

The differences in IOP, vertical cup-to-disc ratios, and mean deviation between the baseline and each follow-up visit were not statistically significant. The baseline average and mean average at 60 months follow-up of the cpRNFL thickness were 106.5±8.5 and 105.1±9.3 μm, respectively; differences between the baseline and each follow-up visit were not statistically significant. The baseline average and mean average at 60 months follow-up of the GCC thickness were 82.8±9. and 81.5±9.2 μm, respectively; differences between baseline and each follow-up visit were not statistically significant.

CONCLUSIONS

The thicknesses of the cpRNFL and GCC did not change in well-maintained optic nerve head findings with normal IOP and visual field during a 5-year follow-up period. Optical coherence tomography evaluations of the thicknesses of the cpRNFL and GCC help accurately diagnose physiological optic disc cupping.

Influence of Trabeculectomy with Mitomycin C on Longitudinal Changes in the Visual Field in Glaucoma Patients with High Myopia

Purpose

To evaluate the effect of trabeculectomy (Trab MMC) on visual field (VF) progression in eyes with glaucoma and high myopia.

Patients and Methods

Patients diagnosed with primary open-angle glaucoma or exfoliation glaucoma who underwent Trab MMC as the first glaucoma surgery along with ≥3 VF tests preoperatively and postoperatively were enrolled. High myopia was defined as an axial length ≥26.5 mm. Postoperative reductions in intraocular pressure (IOP) were assessed by survival analysis using IOP measurements obtained preoperatively. The longitudinal trends of the outcome measures were evaluated using linear mixed models.

Results

Thirty-five eyes of 32 patients were included in this study, including 22 eyes of 20 patients in non-highly myopic group and 13 eyes of 12 patients in highly myopic group. IOP decreased after Trab MMC, and the survival rate did not differ significantly in relation to axial length. Linear mixed-model analyses suggested that the inhibitory effects of Trab MMC on the rate of mean deviation (MD) changes were significant in the non-highly myopic group (-0.53 ± 0.15 dB/year preoperatively to -0.16 ± 0.13 dB/year postoperatively; P = 0.004), but not in the highly myopic group (-0.66 ± 0.19 dB/year preoperatively to -0.48 ± 0.18 dB/year postoperatively; P = 0.32).

Conclusion

Trab MMC reduced IOP in both highly myopic and non-highly myopic eyes, and IOP reduction was very similar in both groups. The VF deterioration rate decreased in both groups, but the change was weaker and nonsignificant in the highly myopic group.

Lamina Cribrosa Morphology in Normal Tension Glaucoma According to the Location of Visual Field Defects

PRCIS

The morphologic alterations in lamina cribrosa (LC) may be related to the location of visual field (VF) defects.

PURPOSE

The aim of this study was to investigate morphologic differences in the LC in normal tension glaucoma (NTG) according to the location of VF defects.

DESIGN

This study was a retrospective, cross-sectional study.

METHODS

Ninety-six eyes of 96 patients with NTG were included in this study. The patients were divided into 2 groups according to the location of VF defects [parafoveal scotoma (PFS) and peripheral nasal step (PNS)]. All patients underwent an optical coherence tomography of the optic disc and macula using swept-source optical coherence tomography (DRI-OCT Triton; Topcon, Tokyo, Japan). The parameters of the optic disc, macula, LC, and connective tissues were compared between the groups. The relationships between the LC parameters and other structures were analyzed.

RESULTS

The temporal peripapillary retinal nerve fiber layer, average macular ganglion cell-inner plexiform layer, and average macular ganglion cell complex were significantly thinner in the PFS than in the PNS group ( P <0.001, P <0.001, and P =0.012, respectively). The PFS group showed a more glaucomatous LC morphology with a smaller lamina cribrosa-global shape index (LC-GSI, P =0.047), more LC defects ( P =0.034), and thinner LC ( P =0.021) than the PNS group. LC-GSI was significantly correlated with LC thickness ( P =0.011) but not with LC depth ( P =0.149).

CONCLUSIONS

In patients with NTG, those with initial PFS showed a more glaucomatous LC morphology than those with initial PNS. The morphologic differences in LC may be related to the location of the VF defects.

Association of Rates of Ganglion Cell and Inner Plexiform Thinning With Development of Glaucoma in Eyes With Suspected Glaucoma

Importance

In eyes with suspected glaucoma, it is clinically relevant to find diagnostic tests for the risk of development of perimetric glaucoma.

Objective

To investigate the association between rates of ganglion cell/inner plexiform layer (GCIPL) and circumpapillary retinal nerve fiber layer (cpRNFL) thinning and the development of perimetric glaucoma in eyes with suspected glaucoma.

Design, Setting, and Participants

This observational cohort study used data collected in December 2021 from a tertiary center study and a multicenter study. Participants with suspected glaucoma were followed up for 3.1 years. The study was designed in December 2021 and finalized in August 2022.

Exposures

Development of perimetric glaucoma was defined as having 3 consecutive results showing abnormal visual fields. Using linear mixed-effect models, rates of GCIPL were compared between eyes with suspected glaucoma that did and did not develop perimetric glaucoma. A joint longitudinal multivariable survival model was used to investigate the performance of rates of GCIPL and cpRNFL thinning in predicting the risk of developing perimetric glaucoma.

Main Outcomes and Measures

Rates of GCIPL thinning and hazard ratio (HR) of developing perimetric glaucoma.

Results

Among a total of 462 participants, the mean (SD) age was 63.3 (11.1) years, and 275 patients (60%) were female. Of 658 eyes, 153 eyes (23%) developed perimetric glaucoma. The mean rates of GCIPL thinning were faster in eyes that developed perimetric glaucoma (-1.28 vs -0.66 μm/y for minimum GCIPL thinning; difference, -0.62; 95% CI, -1.07 to -0.16; P = .02). Based on the joint longitudinal survival model, every 1-μm/y faster rate of minimum GCIPL and rate of global cpRNFL thinning were associated with a 2.4 and 1.9 higher risk of developing perimetric glaucoma, respectively (HR, 2.4; 95% CI, 1.8 to 3.2, and HR, 1.99; 95% CI, 1.76 to 2.22, respectively; P < .001). Among the predictive factors, African American race (HR, 1.56; 95% CI, 1.05 to 2.34; P = .02), male sex (HR, 1.47; 95% CI, 1.02 to 2.15; P = .03), 1-dB higher baseline visual field pattern standard deviation (HR, 1.73; 95% CI, 1.56 to 1.91; P < .001), and 1-mm Hg higher mean intraocular pressure during follow-up (HR, 1.11; 95% CI, 1.05 to 1.17; P < .001) were associated with higher risk of developing perimetric glaucoma.

Conclusions and Relevance

This study found that faster rates of GCIPL and cpRNFL thinning were associated with higher risks of developing perimetric glaucoma. Rates of cpRNFL thinning and specifically GCIPL thinning may be useful measures for monitoring eyes with suspected glaucoma.

Myopic tilted disc: Mechanism, clinical significance, and public health implication

Myopic tilted disc is a common structural change of myopic eyes. With advancing ocular imaging technology, the associated structural changes of the eye, particularly the optic nerve head, have been extensively studied. These structural changes may increase patients' susceptibility to axonal damage and the risk of developing serious optic neuropathies including glaucoma. They also lead to diagnostic difficulties of disease suspects and treatment dilemmas of patients, which implicate clinical practice and subsequently the health care system. In the context of the mounting prevalence of myopia worldwide and its implications to irreversible visual impairment and blindness, it is essential to gain a thorough understanding of the structural changes of myopia. Myopic tilted disc has been extensively investigated by different study groups. However, generalizing the knowledge could be difficult because of the variable definitions of myopic tilted disc utilized in these studies and the complexities of the changes. The current review aimed to clarify the concepts and discuss various aspects of myopic tilted disc, including the definitions, association with other myopia-related changes, mechanism of tilted disc development, structural and functional changes, and clinical implications.

Nanoparticles for the treatment of glaucoma-associated neuroinflammation

Recently, a considerable amount of literature has emerged around the theme of neuroinflammation linked to neurodegeneration. Glaucoma is a neurodegenerative disease characterized by visual impairment. Understanding the complex neuroinflammatory processes underlying retinal ganglion cell loss has the potential to improve conventional therapeutic approaches in glaucoma. Due to the presence of multiple barriers that a systemically administered drug has to cross to reach the intraocular space, ocular drug delivery has always been a challenge. Nowadays, studies are focused on improving the current therapies for glaucoma by utilizing nanoparticles as the modes of drug transport across the ocular anatomical and physiological barriers. This review offers some important insights on the therapeutic advancements made in this direction, focusing on the use of nanoparticles loaded with anti-inflammatory and neuroprotective agents in the treatment of glaucoma. The prospect of these novel therapies is discussed in relation to the current therapies to alleviate inflammation in glaucoma, which are being reviewed as well, along with the detailed molecular and cellular mechanisms governing the onset and the progression of the disease.

Microvasculature Dropout and Development of Normal Tension Glaucoma in Glaucoma Suspects: The Normal Tension Glaucoma Suspect Cohort Study: Microvasculature dropout and Normal-Tension Glaucoma

PURPOSE

To investigate the contribution of vessel parameters to identify normal tension glaucoma (NTG) suspects at risk of NTG development.

DESIGN

Multicenter prospective cohort study.

SUBJECTS

A total of 307 eyes of 307 NTG suspects having intraocular pressure within the normal range; a suspicious optic disc, but without definite localized retinal nerve fiber layer (RNFL) defects; and a normal visual field (VF).

METHODS

To measure laminar vessel density (VD), the VD was measured in the intradisc region from images of the deep vascular layers of optical coherence tomography angiography (OCT-A). Conversion to NTG was defined either by a new localized RNFL defect in the superotemporal or inferotemporal region, or the presence of a glaucomatous VF defect on two consecutive tests according to the pattern standard deviation plots.

MAIN OUTCOME MEASURE

Conversion to NTG.

RESULTS

In total, 73 (23.8%) of the 307 NTG suspects converted to NTG during the follow-up period of 59.84 ± 12.44 months. Detection rate of microvasculature dropout (MvD) was significantly higher in NTG suspects who progressed to NTG (50.7%) than in those who did not (6.4%; P < 0.001). The macular deep VD (P = 0.006) and laminar deep VD (P = 0.004) were significantly lower in NTG suspects who progressed to NTG. The presence of MvD (P < 0.001) and lower laminar deep VD (P = 0.006) were significantly associated with NTG conversion.

CONCLUSIONS

NTG suspects with baseline MvD or a lower laminar deep VD on OCT-A had a higher risk of conversion.

Comparison between frequency-doubling technology perimetry and standard automated perimetry in early glaucoma

This study aimed to find out the significance of the difference between frequency-doubling technology perimetry (FDT) and standard automated perimetry (SAP) in terms of the detected visual field (VF) damage, and evaluate associated factors to SAP–FDT difference in early glaucoma. Glaucoma patients in early stage (MD better than − 6.0 decibel, 96 eyes) were included in this cross-sectional study. We subtracted mean deviation (MD) and pattern standard deviation (PSD) of FDT from those of SAP, respectively. Additionally, we counted significantly depressed points of P < 5% and P < 1% on the pattern deviation probability plot of both FDT and SAP and defined eyes with significant SAP–FDT difference when the number of abnormal points were greater than 4 points on FDT. We measured lamina cribrosa depth (LCD) and lamina cribrosa curvature index (LCCI) for structural parameters of the optic nerve head from images using enhanced depth imaging of the optical coherence tomography (OCT). Peripapillary vessel density (VD) and presence of microvasculature dropout (MvD), the complete loss of choriocapillaris in localized regions of parapapillary atrophy, was evaluated using deep layer map of OCT angiography (OCT-A) for vascular parameters. Peripheral nasal step (PNS) group had an isolated glaucomatous VF defect within nasal periphery outside 10° of fixation. Parafoveal scotoma (PFS) group had an isolated glaucomatous VF defect within 12 points of a central 10˚ radius. Eyes with significant SAP–FDT difference showed higher detection of MvD on deep layer map of OCT-A, greater LCD, and greater LCCI (all P < 0.05, respectively). In logistic regression analysis, frequent presence of MvD, less presence of disc hemorrhage, and greater LCD were significantly associated with significant SAP–FDT difference. Sub-analysis was performed in eyes with PNS (50 eyes) and PFS (46 eyes). SAP–FDT difference of MD value showed positive association with peripapillary VD on deep layer of OCT-A, which was significant in eyes with PFS compared to eyes with PNS. SAP–FDT difference of PSD value showed negative association with LCCI and LCD, which was significant in eyes with PNS compared to eyes with PFS. Glaucomatous eyes classified by the difference of the detected VF damage on FDT versus SAP showed different clinical features. Greater SAP–FDT difference was significantly associated with structural parameters such as LCD and LCCI. Less SAP–FDT difference was associated with presence of disc hemorrhage and lower deep layer peripepillary VD. There is possibility to use the difference of SAP and FDT to identify associated risk factors in glaucoma patients.

Role of ocular blood flow in normal tension glaucoma

Background

Normal tension glaucoma (NTG) is a multifactorial disease in the pathogenesis of which intraocular pressure (IOP)-independent factors play a key role.

Main text

There is considerable evidence that impairment of the ocular blood flow (OBF) is involved both in the onset and progression of this disease. With the development of the hypothesis of OBF in NTG, various imaging techniques have been developed to evaluate the OBF and blood vessels. Moreover, vascular dysregulation, which is a main factor in Flammer syndrome, was frequently observed in NTG patients. Disturbed OBF leads to increased oxidative stress, which plays an important role in the pathogenesis of glaucomatous optic neuropathy. These results suggested that IOP-independent management may provide alternative treatment options for NTG patients.

Conclusions

In this review, we mainly focus on the mechanisms of the abnormal OBF in NTG.