Steroids in the treatment of nonarteritic anterior ischemic optic neuropathy: A PRISMA-compliant meta-analysis

Short-term deterioration of visual acuity and visual fields in non-arteritic anterior ischemic optic neuropathy

PURPOSE

To determine the frequency and severity of further visual loss experienced by patients within ten weeks from diagnosis of acute non-arteritic anterior ischemic optic neuropathy. (NAION).

DESIGN

Retrospective case series.

METHODS

Electronic medical records (EMR) at an academic neuro-ophthalmology practice were searched for diagnosis of "NAION" and all identified charts were reviewed to determine eligibility. Patients diagnosed with acute NAION between February 2014 and December 2023 who presented within four weeks of symptom onset and were seen in follow-up within ten weeks were included. Clinically significant decline in best corrected visual acuity (BCVA) and peripheral VF were defined as decline of BCVA ≥2 Snellen lines and decrease of ≥2 decibels (dB) in mean deviation (MD) on perimetric testing.

RESULTS

Forty-nine eyes met inclusion and exclusion criteria. Sixty-seven percent of patients were male and average age at presentation was 66 years. Twenty-two percent of eyes demonstrated worsening of BCVA by ≥2 lines. Of these, 55% worsened by ≥4 lines and 27% by ≥8 lines. In 27% of eyes MD on perimetry worsened by ≥2 dB and in 18% by ≥4 dB. In total, 41% of eyes demonstrated clinically significant worsening of BCVA or VF.

CONCLUSIONS

Subacute deterioration of BCVA and/or VF following acute NAION is not uncommon while optic disc edema is present, with sizeable proportion of patients experiencing dramatic visual decline. Deterioration in visual function within the first 10 weeks of presentation does not exclude the diagnosis of NAION and further investigations should only be performed if additional clinical features are discordant with this diagnosis.

Clinical efficacy of dexamethasone parabulbar injection in patients with Nonarteritic anterior ischemic optic neuropathy

Background

Nonarteritic anterior ischemic optic neuropathy (NAAION) is a common optic neuropathy that often leads to significant visual acuity loss in patients. The present study evaluated the effects of parabulbar dexamethasone injection on visual outcomes in patients with NAAION.

Methods

This retrospective case-control study included patients diagnosed with NAAION between January 2019 and December 2022. Thirty-four patients with NAAION (34 eyes) received dexamethasone parabulbar injections, while 39 patients with NAAION (39 eyes) received oral corticosteroid treatment (control group). Best-corrected visual acuity (BCVA), visual field (VF) defect, and retinal nerve fiber layer (RNFL) thickness of the affected eye were compared between groups at baseline and 2, 6, and 12 weeks post-treatment.

Results

Mean BCVA significantly improved after 6 and 12 weeks in the injection groups compared with the control group (all P < 0.01). The visual field indices, mean deviation and pattern standard deviation significantly improved in the injection group compared with the control group after 2, 6, and 12 weeks (all P < 0.01). The RNFL showed a remarkable decrease in edema after 6 weeks (superior and nasal P values 0.005 and 0.013, respectively) in the injection group compared with the control group. Significant RNFL thinning was also observed in superior, inferior, temporal, and nasal quadrants in the control group after 12 weeks (all P values < 0.01). Also, fewer side effects were observed in the injection group compared to the control group.

Conclusions

The results of this study suggested that dexamethasone parabulbar injection might be a safe and effective intervention for relieving visual acuity and VF in patients with NAAION.

Appropriate patient population for future visual system axon regeneration therapies

A number of blinding diseases caused by damage to the optic nerve result in progressive vision loss or loss of visual acuity. Secondary glaucoma results from traumatic injuries, pseudoexfoliation or pigmentary dispersion syndrome. Progressive peripheral vision loss is common to all secondary glaucoma irrespective of the initial event. Axon regeneration is a potential therapeutic avenue to restore lost vision in these patients. In contrast to the usual approach of having the worst possible patient population for initial therapies, axon regeneration may require consideration of appropriate patient population even for initial treatment trials. The current state of axon regeneration therapies, their potential future and suitable patient population when ready is discussed in this perspective. The selection of patients are important for adoption of axon regeneration specifically in the areas of central nervous system regenerative medicine. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology Neurological Diseases > Biomedical Engineering Metabolic Diseases > Molecular and Cellular Physiology.

Non-Arteritic Anterior Ischemic Optic Neuropathy (NA-AION): A Comprehensive Overview

Non-arteritic anterior ischemic optic neuropathy (NA-AION) represents one of the most important causes of blindness or severely impaired vision in middle-aged and elderly people. Unilateral optic disc edema and abrupt, painless vision loss are its defining features. It is commonly assumed that NA-AION is caused by an ischemic infarction of the optic nerve head, and, although the exact pathogenesis is still unknown, several risk factors and comorbidities associated with its development have been found. NA-AION occurs generally in patients older than 50 years who have small optic discs and vasculopathy risk factors. Even though numerous treatment options have been proposed, no available effective medical or surgical therapy or prophylactic measure for NA-AION currently exists. The purpose of present-day therapeutic strategies is therefore to identify and possibly control any underlying modifiable risk factors, aiming to prevent the development of new NA-AION episodes in the affected and fellow eye. A thorough assessment of NAION, including its history, epidemiology, etiology, pathophysiology, risk factors, associated comorbidities, clinical findings, diagnostic tests, treatment choices, prognosis, and future research, is the goal of this work.

Non-Arteritic Anterior Ischemic Optic Neuropathy (NA-AION): A Comprehensive Overview

Non-arteritic anterior ischemic optic neuropathy (NA-AION) represents one of the most important causes of blindness or severely impaired vision in middle-aged and elderly people. Unilateral optic disc edema and abrupt, painless vision loss are its defining features. It is commonly assumed that NA-AION is caused by an ischemic infarction of the optic nerve head, and, although the exact pathogenesis is still unknown, several risk factors and comorbidities associated with its development have been found. NA-AION occurs generally in patients older than 50 years who have small optic discs and vasculopathy risk factors. Even though numerous treatment options have been proposed, no available effective medical or surgical therapy or prophylactic measure for NA-AION currently exists. The purpose of present-day therapeutic strategies is therefore to identify and possibly control any underlying modifiable risk factors, aiming to prevent the development of new NA-AION episodes in the affected and fellow eye. A thorough assessment of NAION, including its history, epidemiology, etiology, pathophysiology, risk factors, associated comorbidities, clinical findings, diagnostic tests, treatment choices, prognosis, and future research, is the goal of this work.

Prolonged Exposure to High Glucose Induces Premature Senescence Through Oxidative Stress and Autophagy in Retinal Pigment Epithelial Cells

Chronic hyperglycemia involves persistent high-glucose exposure and correlates with retinal degeneration. It causes various diseases, including diabetic retinopathy (DR), a major cause of adult vision loss. Most in vitro studies have investigated the damaging short-term effects of high glucose exposure on retinal pigment epithelial (RPE) cells. DR is also a severe complication of diabetes. In this study, we established a model with prolonged high-glucose exposure (15 and 75 mM exogenous glucose for two months) to mimic RPE tissue pathophysiology in patients with hyperglycemia. Prolonged high-glucose exposure attenuated glucose uptake and clonogenicity in ARPE-19 cells. It also significantly increased reactive oxygen species levels and decreased antioxidant protein (superoxide dismutase 2) levels in RPE cells, possibly causing oxidative stress and DNA damage and impairing proliferation. Western blotting showed that autophagic stress, endoplasmic reticulum stress, and genotoxic stress were induced by prolonged high-glucose exposure in RPE cells. Despite a moderate apoptotic cell population detected using the Annexin V-staining assay, the increases in the senescence-associated proteins p53 and p21 and SA-β-gal-positive cells suggest that prolonged high-glucose exposure dominantly sensitized RPE cells to premature senescence. Comprehensive next-generation sequencing suggested that upregulation of oxidative stress and DNA damage-associated pathways contributed to stress-induced premature senescence of ARPE-19 cells. Our findings elucidate the pathophysiology of hyperglycemia-associated retinal diseases and should benefit the future development of preventive drugs. Prolonged high-glucose exposure downregulates glucose uptake and oxidative stress by increasing reactive oxygen species (ROS) production through regulation of superoxide dismutase 2 (SOD2) expression. Autophagic stress, ER stress, and DNA damage stress (genotoxic stress) are also induced by prolonged high-glucose exposure in RPE cells. Consequently, multiple stresses induce the upregulation of the senescence-associated proteins p53 and p21. Although both apoptosis and premature senescence contribute to high glucose exposure-induced anti-proliferation of RPE cells, the present work shows that premature senescence rather than apoptosis is the dominant cause of RPE degeneration, eventually leading to the pathogenesis of DR.

Intravitreal Aflibercept for Patients with Acute Nonarteritic Anterior Ischemic Optic Neuropathy: A Retrospective Trial

PURPOSE

This study aimed to investigate whether intravitreal aflibercept was safe and effective in patients with acute nonarteritic anterior ischemic optic neuropathy (NAION).

METHODS

This was a chart study of 25 individuals with acute NAION (25 eyes). An intravitreal injection of 2 mg/0.05 mL of aflibercept was administered to fifteen participants. The remaining ten patients in the control group were given standard care. The researchers measured the initial visual acuity, retinal nerve fiber layer thickness (RNFLT), and automated perimetry. During the follow-up period, the researchers measured the final visual acuity, RNFLT, automated perimetry, and side effects.

RESULTS

Visual acuity and visual field assessment were significantly improved in the study group, and optical coherence tomography testing demonstrated significant disc edema resolution. The therapy results differed significantly between the two groups regarding visual outcomes (F = 0.027, p = 0.039) and RNFLT decrease (F = 5.507, p = 0.003). However, the difference in visual field alterations was not significant (F = 0.724, p = 0.387).

CONCLUSIONS

Intravitreal injection of aflibercept can significantly improve visual acuity and resolve disc edema in patients with acute NAION. Intravitreal aflibercept may be an alternative treatment for acute NAION. However, a large series investigation is needed to assess the long-term therapeutic benefit and safety of intravitreal aflibercept in patients with acute NAION.

The Efficacy of Glucocorticoids in the Treatment of Nonarteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis

Background

To evaluate the clinical effects and safety of glucocorticoids for patients with nonarteritic anterior ischemic optic neuropathy (NAION).

Methods

The databases MEDLINE, Embase, PubMed, Cochrane Database, and Web of Science were used to search for the relevant studies, and full-text articles that reported on the evaluation of glucocorticoids vs. no-treatment or placebo for patients with NAION. Review Manager 5.4 was used to estimate the pooled effects of the results among selected studies. Forest plots, funnel plots, and Begg's rank correlation were also performed on the included articles.

Results

A total of 983 patients were contained in the 9 studies that satisfied the eligibility criteria. The meta-analysis showed that, compared with the control group, the glucocorticoid group had significantly improved the VA (MD: -0.25, 95% CI [-0.45, -0.05], P = 0.02), VF (MD: -0.50, 95% CI [-0.94, -0.07], P = 0.02), and RNFL (MD: -14.10, 95% CI [-26.41, -1.79], P = 0.02) in NAION patients and had a high improvement rate of VA (RR 1.31, 95% CI [1.12, 1.52], P = 0.0005). No significant publication bias was observed in our study. Discussion. Our research preliminarily confirmed the effectiveness of glucocorticoids for NAION treatment, but more high-quality RCTs focusing on the hormone adverse reactions should be performed to verify our conclusions.

Efficacy of Treatments in Nonarteritic Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis

BACKGROUND

Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) is the second most common cause of optic nerve-related permanent visual loss in adults.

AIM

We aimed to analyze the efficacy of the noninvasive and minimally invasive therapeutic options of NAION.

METHODS

We performed a systematic literature search in MEDLINE, EMBASE, and CENTRAL from inception to 10 June 2019 to identify the studies that report on the effect of different therapies on visual acuity (VA) and visual field (VF). Weighted mean difference (WMD) with 95% confidence interval (CI) was calculated for these outcomes. The efficacy of steroids was investigated in quantitative, oxygen, steroid plus erythropoietin (EPO), levodopa/carbidopa, memantine, and heparin-induced extracorporeal LDL/fibrinogen precipitation (HELP) therapies and other therapeutic modalities in qualitative synthesis.

RESULTS

Thirty-two studies were found to be eligible. We found that steroid therapy compared to control did not improve VA (p = 0.182, WMD = 0.14, 95% CI: -0.07, 0.35) or VF (p = 0.853, WMD = 0.16, 95% CI: -1.54, 1.86). Qualitative analysis could be performed for oxygen, steroid plus EPO, and HELP as well, however, none of them showed VA and VF benefit. Two individual studies found memantine and levodopa beneficial regarding VA.

CONCLUSION

Our systematic review did not reveal any effective treatment. Further investigations are needed to find therapy for NAION.