Nonarteritic anterior ischemic optic neuropathy and obstructive sleep apnea

The Effect of Semaglutide and GLP-1 RAs on Risk of Nonarteritic Anterior Ischemic Optic Neuropathy

PURPOSE

The association between GLP-1 receptor agonists (GLP-1RA) and nonarteritic anterior ischemic optic neuropathy (NAION) remains unclear. Given the debilitating sequelae of NAION and rapid increase of GLP-1RA use, further research is essential to investigate this potential relationship. This study seeks to determine the risk of NAION and ischemic optic neuropathy (ION) in patients prescribed GLP-1RAs.

DESIGN

Retrospective matched cohort study.

SETTING

TriNetX United States collaborative network.

PARTICIPANTS

Patients ≥12 years old with type 2 diabetes (T2DM) and considered overweight or obese (high BMI), with at least one ophthalmology or neurology visit. Among T2DM patients, approximately 120,000 patients with a semaglutide prescription and 220,000 prescribed any GLP-1RA were compared to matched T2DM controls. Among high BMI patients, approximately 58,000 on semaglutide and 66,000 on any GLP-1RA were compared to matched controls.

METHODS

Patients prescribed semaglutide or any GLP-1RA were compared with those on non-GLP-1RA medications. Populations were propensity matched (1:1) on various demographic and risk factors to balance baseline cohorts.

MAIN OUTCOMES AND MEASURES

Cumulative incidence and risk of NAION and ION. Risk ratios (RR) with 95% confidence intervals (CI) were reported, with significance defined as CI <0.9 or > 1.1.

RESULTS

In T2DM patients prescribed semaglutide, the risk of NAION (RR = 0.7, 95% CI: 0.523-0.937) and ION (RR = 0.788, 95% CI: 0.609-1.102) after 5 years was not significantly increased compared to matched T2DM controls. Similarly, T2DM patients on any GLP-1RA demonstrated no significant difference in the risk of NAION (RR = 0.887, 95% CI: 0.735-1.071) or ION (RR = 0.969, 95% CI: 0.813-1.154) compared to controls. Furthermore, no increased risk of either outcome was found in the high BMI groups prescribed semaglutide or any GLP-1RA. The cumulative 5-year risk of NAION and ION in T2DM patients on semaglutide was 0.065% and 0.08%, respectively. In those with high BMI prescribed semaglutide, the risk of NAION and ION after 2 years was 0.038% and 0.404%, respectively.

CONCLUSIONS

There was no significant increase in risk of NAION or ION in patients taking semaglutide or GLP-1RAs compared to T2DM or high BMI controls.

Study of nycthemeral variations in blood pressure in patients with non-arteritic anterior ischemic optic neuropathy

PURPOSE

The objective of this study was to analyze the nycthemeral variations in blood pressure (BP) in individuals who presented with non-arteritic anterior ischemic optic neuropathy (NAION).

METHODS

BP was recorded for 24 h (ambulatory blood pressure monitoring, ABPM) in 65 patients with acute NAION. Three definitions of nighttime periods were used: definition 1, 1 a.m.-6 a.m.; definition 2, 10 p.m.-7 a.m.; and definition 3, 10 p.m.-8 a.m. For each of these definitions, patients were classified according to the value of nocturnal reduction in BP into dippers (10-20%), mild dippers (0-10%), reverse dippers (< 0%), and extreme dippers (> 20%).

RESULTS

The proportions of dippers, mild dippers, reverse dippers, and extreme dippers varied significantly depending on the definition chosen. We found the highest number of patients with extreme dipping (23%) when using the strictest definition of nighttime period (definition 1, 1 a.m.-6 a.m.), as compared with 6.2% and 1.5% for the other definitions, respectively. Overall, 13 of 33 patients without known systemic hypertension (39%) were diagnosed with hypertension after ABPM. No risk factor for NAION was associated with the extreme-dipping profile. Finally, the prevalence of systemic hypertension was high (69%).

CONCLUSION

In our population of patients who had an episode of NAION, the proportion of extreme dippers was higher than that usually found in the literature. However, extreme dipping is not a frequent feature of patients with NAION as compared to patients with systemic hypertension. ABPM is recommended for all patients with NAION and unknown history of systemic hypertension.

Ocular manifestations of obstructive sleep apnea: a systematic review and meta-analysis

BACKGROUND

The association of obstructive sleep apnea (OSA) with development of eye diseases is unclear. This current systematic review and meta-analysis attempts to summarize and analyze associations between OSA and ocular disorders in the literature.

METHODS

PubMed, EMBASE, Google Scholar, Web Of Science, and Scopus databases were searched from 1901 to July 2022 in accordance with the Preferred Reporting in Systematic Review & Meta-Analysis (PRISMA). Our primary outcome assessed the association between OSA and the odds of developing floppy eyelid syndrome (FES), glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), retinal vein occlusion (RVO), keratoconus (KC), idiopathic intracranial hypertension (IIH), age-related macular degeneration (AMD), and central serous chorioretinopathy (CSR) through odds ratio calculated at the 95% confidence interval.

RESULTS

Forty-nine studies were included for systematic review and meta-analysis. The pooled OR estimate was highest for NAION [3.98 (95% CI 2.38, 6.66)], followed by FES [3.68 (95% CI 2.18, 6.20)], RVO [2.71(95% CI 1.83, 4.00)], CSR [2.28 (95% CI 0.65, 7.97)], KC [1.87 (95% CI 1.16, 2.99)], glaucoma [1.49 (95% CI 1.16, 1.91)], IIH [1.29 (95% CI 0.33, 5.01)], and AMD [0.92 [95% CI 0.24, 3.58] All observed associations were significant (p < 0.001) aside from IIH and AMD.

CONCLUSION

OSA is significantly associated with NAION, FES, RVO, CSR, KC, and glaucoma. Clinicians should be informed of these associations so early recognition, diagnosis, and treatment of eye disorders can be addressed in at-risk groups, and early referral to ophthalmic services is made to prevent vision disturbances. Similarly, ophthalmologists seeing patients with any of these conditions should consider screening and referring patients for assessment of possible OSA.

Characteristics of macrophage-like cells in acute nonarteritic anterior ischemic optic neuropathy and the normal fellow eyes on en face optical coherence tomography

Purpose

To quantitatively analyze macrophage-like cells (MLCs) at the vitreoretinal interface (VRI) in acute nonarteritic anterior ischemic optic neuropathy (NAION) using en face swept-source optical coherence tomography (OCT).

Methods

Twenty-five acute NAION eyes and 25 normal fellow eyes from 25 patients were included in the study. MLCs were visualized in a 3 μm 6 mm×6 mm en face OCT slab above the VRI centered on the optic nerve head (ONH). After semiautomatic binarization and quantification, we evaluated the MLC density between the two groups. We also investigated the relationship between MLC density and other OCT parameters, including the increase in peripapillary retinal nerve fiber layer (RNFL) thickness and loss of vessel density (VD) in radical peripapillary capillary (RPC).

Results

The MLC density in the affected eye of the ONH was highly correlated with that in the fellow eye (r=0.612, p=0.001). The MLC density significantly increased in acute NAION eyes (NAION vs. normal, 11.97 ± 6.66 vs. 9.31 ± 6.10 cell/mm², p=0.028). In sectorial analysis, the increase in MLCs was mainly in the superior regions (4.13 ± 7.49 vs. 0.94 ± 5.21 cell/mm², p=0.001). The VD of RPC decreased significantly in the affected eyes (NAION vs. normal, 37.54 ± 5.25 vs. 40.56 ± 4.25, p=0.016), and the loss of RPC was predominantly in the superior sectors and the temporal sectors when compared to the inferior sectors and the nasal sectors, respectively (superior vs. inferior, -3.54 ± 6.71 vs. -0.37 ± 8.07, p=0.004; temporal vs. nasal, -2.69 ± 8.72 vs. -1.22 ± 6.06, p=0.005). The loss of RPC and the increase in MLC density were greater in affected sector corresponding to the visual field (VF) defect.

Conclision

MLCs located above the VRI increased significantly in acute NAION eyes, especially in subregions corresponding to VF defect, which provides clinical evidence supporting that the inflammatory response participates in the pathological process of NAION. The magnitude of the increase in MLCs corresponds to the RPC loss in the quadrant analysis.

Risk Factors for Fellow Eye Involvement in Patients with Nonarteritic Anterior Ischemic Optic Neuropathy

INTRODUCTION

The aim of the study was to investigate the possible risk factors for fellow eye involvement in patients with nonarteritic anterior ischemic optic neuropathy (NAION).

METHODS

A total of 113 patients with unilateral NAION attack were included and divided into two groups according to whether fellow eye involvement was present over a mean follow-up period of 2.70 years (P25-P75: 0.77-3.54 years). General characteristics (including age, sex, diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea syndrome [OSAS]) and ocular characteristics (including initial best-corrected visual acuity, initial visual field damage of the first eye, and the presence/absence of a crowded disc) were analyzed and compared between the two groups. Cox regression was used to assess the risk factors for fellow eye involvement.

RESULTS

During the follow-up period, 40 patients developed fellow eye involvement. The initial best-corrected visual acuity (p = 0.048) and mean deviation of the visual field (VF) (p = 0.039) of the first eye in patients with fellow eye involvement were worse than those in patients without it. Diabetes (HR = 3.06, 95% CI: 1.50, 6.26, p = 0.002) and increased VF damage (moderate vs. mild, HR = 2.92, 95% CI: 1.03, 8.25, p = 0.043; severe vs. mild, HR = 5.01, 95% CI: 1.65, 15.20, p = 0.004) were associated with a significantly increased risk of fellow eye involvement. In 57 patients with apnea-hypopnea index (AHI) data for further study, an AHI score ≥23.2 was also found to be a risk factor (HR = 3.36, 95% CI: 1.17, 9.69, p = 0.025).

CONCLUSION

Diabetes, severer initial VF damage, and more severe OSAS were risk factors for fellow eye involvement in NAION. For patients with these risk factors, more intensive follow-ups might be warranted.

Analysis of Systemic Risk Factors and Post-Insult Visual Development in a Danish Cohort of Patients with Nonarteritic Anterior Ischemic Optic Neuropathy

Purpose

Nonarteritic anterior ischemic optic neuropathy (NAION) is associated with vascular as well as anatomical risk factors. Following the insult, the visual development varies from minor to severe deterioration. The aim of this study was to examine possible prognostic systemic risk factors and their eventual impact on post-insult visual development in NAION patients.

Methods

A retrospective chart review of all NAION patients (18-79 years at time of diagnosis) seen a minimum of two times in a tertiary eye department during a 10-year period in regard to systemic diseases, medication, lifestyle factors and ophthalmic examination was performed. Visual outcome was assessed according to the development of best corrected visual acuity (BCVA) and visual field from initial to final visit.

Results

There were 163 eligible patients. A greater proportion of the patients in the total cohort were over 50 years of age (79.8%) and men (66.3%). In total, 59.5% of the patients had a stable BCVA, while 25.8% experienced improvement, and 14.7% had deterioration. Seventy-two percent of the patients had a stable visual field, while 14% had improvement, and 14% had deterioration. No association between visual outcome and clinical characteristics, medication or systemic risk factors were identified.

Conclusion

We did not find any association between patient characteristics and systemic risk factors at time of diagnosis and visual development post-insult. This could suggest that the optic nerve head anatomy plays a larger role for visual outcome than previously estimated.

Sleep and eye disease: A review

There is a growing body of literature on the effects of sleep disorders, in particular obstructive sleep apnoea (OSA), on ocular health, with consistent evidence of an increased risk of floppy eyelid syndrome, non-arteritic anterior ischaemic optic neuropathy, diabetic macular oedema, and other retinal vasculature changes in individuals with OSA. However, reports on OSA's associations with glaucoma, papilloedema, diabetic retinopathy, central serous chorioretinopathy, and keratoconus have been conflicting, while links between OSA and age-related macular degeneration have only been described fairly recently. Despite numerous suggestions that OSA treatment may reduce risk of these eye diseases, well-designed studies to support these claims are lacking. In particular, the ocular hypertensive effects of continuous positive airway pressure (CPAP) therapy for OSA requires further investigation into its potential impact on glaucoma risk and management. Reports of ocular surface complications secondary to leaking CPAP masks highlights the importance of ensuring good mask fit. Poor sleep habits have also been linked with increased myopia risk; however, the evidence on this association remains weak.

Sleep apnea and eye diseases: evidence of association and potential pathogenic mechanisms

Eye diseases are an important group of increasingly prevalent disorders that contribute very significantly to disability and represent a considerable health burden. Some data suggest that several of these diseases may be associated with sleep-disordered breathing, mainly obstructive sleep apnea (OSA), due to intermediate mechanisms, such as intermittent hypoxia or sleep fragmentation. The aims of this systematic review were to identify and critically evaluate the current evidence supporting the existence of a possible relationship between OSA and the more relevant eye diseases as well as to evaluate the potential pathogenic mechanisms. There is a body of largely low-level evidence for the association of OSA with glaucoma, nonarteritic ischemic optic neuropathy, central serous chorioretinopathy, and diabetic retinopathy. Meta-analysis of available case-control studies shows that OSA increases the risk of glaucoma (pooled odds ratio: 1.50; 95% confidence interval: 1.25 to 1.80; P < .001), nonarteritic ischemic optic neuropathy (3.62; 1.94 to 6.76; P < .001), and diabetic retinopathy (1.57; 1.09 to 2.27; P = .02). Moreover, several pathogenic pathways have been identified, mainly related to hypoxic damage, mechanical stress, systemic inflammation, oxidative stress, sympathetic tone, and endothelial dysfunction. In contrast, information about the effect of apnea-hypopnea suppression on the development and progression of eye damage is either nonexistent or of a very low level of evidence. In conclusion, OSA has emerged as an additional potential risk factor for many eye diseases, although their link is weak and contradictory, so further examination is required.

CITATION

García-Sánchez A, Villalaín I, Asencio M, García J, García-Rio F. Sleep apnea and eye diseases: evidence of association and potential pathogenic mechanisms. J Clin Sleep Med. 2022;18(1):265-278.

Risk Factors for Non-arteritic Anterior Ischemic Optic Neuropathy: A Large Scale Meta-Analysis

Objective: We conducted a meta-analysis to explore all the potential risk factors for non-arteritic anterior ischemic optic neuropathy (NAION) based on the published literature. Methods: A comprehensive literature search through the online databases was performed to obtain studies concerning the risk factors of NAION up to June 2020. Pooled unadjusted odds ratios (ORs) or rate ratios (RRs) were calculated to evaluate the weight of risk factors. This study was registered in PROSPERO under the number CRD42018084960. Results: Our meta-analysis included 49 original studies comprising of more than 10 million patients. The following risk factors were proved to be significantly associated with NAION: male gender (OR = 1.67, 95% CI: 1.50-1.85, P < 0.00001), hypertension (RR = 1.28, 95% CI: 1.20-1.37, P < 0.00001), hyperlipidemia (RR = 1.43, 95% CI: 1.26-1.62, P < 0.00001), diabetes mellitus (DM) (RR = 1.53, 95% CI: 1.36-1.73, P < 0.00001), coronary heart disease (CHD) (RR = 1.68, 95% CI: 1.24-2.27, P = 0.0008), sleep apnea (RR = 3.28, 95% CI: 2.08-5.17, P < 0.00001), factor V Leiden heterozygous (RR = 2.21, 95% CI: 1.19-4.09, P = 0.01), and medication history of cardiovascular drugs. Conclusion: We concluded that the above risk factors were significantly related to NAION. Better understanding of these risk factors in NAION can help the direct therapeutic approaches.

Comparison of the choroidal structural components and choroidal vascularity index between patients with obstructive sleep apnea syndrome and healthy controls

AIM

To compare the choroidal structural components and choroidal vascularity index (CVI) between patients with obstructive sleep apnea syndrome (OSAS) and healthy controls.

METHODS

The choroidal images of the eyes of patients with OSAS and healthy controls, which were obtained by using enhanced depth imaging optical coherence tomography (EDI-OCT), were binarized into luminal area (LA) and stromal area (SA) using the ImageJ software. CVI was calculated as the ratio of LA to the total choroid area (TCA). The CVI, LA, SA, and TCA measurements were compared between the groups.

RESULTS

Seventy-one eyes of 57 patients, 33 eyes of 27 patients with OSAS and 38 eyes of 30 healthy individuals, were included. The mean age of all patients was 46.77±9.75 (range, 30-67) years. There was no statistically significant difference for age, sex, axial length (AL) or the side of the eyes between the groups (p>0.05). The mean body mass index (BMI) of the patients was significantly higher in the OSAS group (p<0.05). The mean CVI value was 68.33±1.81% in the OSAS group and 69.21±1.27% in the control group (p<0.05). There was no statistically significant difference for the mean values of LA, SA, and TCA between the groups (p>0.05). No significant correlation was found between the polysomnography test results and the choroidal measurements (p>0.05).

CONCLUSION

In our study, CVI was found to be lower in patients with OSAS than in the healthy controls. Further studies with larger sample sizes are required to evaluate the role of CVI in OSAS.

The Associations of Obstructive Sleep Apnea and Eye Disorders: Potential Insights into Pathogenesis and Treatment

Purpose of Review

Obstructive sleep apnea (OSA) patients are at significantly increased risks for cardiovascular and cerebrovascular morbidities. Recently, there has been heightened interest in the association of OSA with numerous ocular diseases and possible improvement of these conditions with the initiation of OSA treatment. We reviewed the current evidence with an emphasis on the overlapping pathogeneses of both diseases.

Recent Findings

Currently available literature points to a substantial association of OSA with ocular diseases, ranging from those involving the eyelid to optic neuropathies and retinal vascular diseases. Since the retina is one of the highest oxygen-consuming tissues in the body, the intermittent hypoxia and hypercapnia ensuing in OSA can have deleterious effects on ocular function and health. Tissue hypoxia, autonomic dysfunction, microvascular dysfunction, and inflammation all play important roles in the pathogenesis of both OSA and ocular diseases. Whether OSA treatment is capable of reversing the course of associated ocular diseases remains to be determined. It is anticipated that future therapeutic approaches will target the common underlying pathophysiologic mechanisms and promote favorable effects on the treatment of known associated ocular diseases.

Summary

Emerging evidence supports the association of ocular diseases with untreated OSA. Future studies focusing on whether therapeutic approaches targeting the common pathophysiologic mechanisms will be beneficial for the course of both diseases are warranted.

Evaluation of Retinal Nerve Fiber Layer Thickness and Optic Nerve Head Parameters in Obstructive Sleep Apnoea Patients

PURPOSE

To study the retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) parameters in obstructive sleep apnoea (OSA) patients and their relationship with severity of the disease.

METHODS

A cross-sectional, hospital-based study. Fifty-four OSA subjects and 54 controls were recruited. Candidate that fulfil the criteria with normal ocular examinations then proceed with spectrum domain Cirrus optical coherence tomography examinations. ONH parameters and RNFL thickness were evaluated. Apnoea-hypopnoea index (AHI) of the OSA group were obtained from the medical record.

RESULTS

In OSA, mean of average RNFL thickness was 93.87 µm, standard deviation (SD) = 9.17, p = 0.008 (p < 0.05) while superior RNFL thickness was 113.59 µm, SD = 16.29, p ≤ 0.001 (p < 0.05). RNFL thickness fairly correlate with severity of the disease (AHI), superior RNFL with R = 0.293, R2 = 0.087, p = 0.030 (p < 0.05), and nasal RNFL R = 0.292, R2 = 0.085, p = 0.032. No significant difference and correlation observed on ONH parameters. In control group, mean of average RNFL thickness was 98.96 µm, SD = 10.50, p = 0.008 (p < 0.05) while superior RNFL thickness was 125.76 µm, SD = 14.93, p ≤ 0.001 (p < 0.05).

CONCLUSIONS

The mean of the average and superior RNFL thickness were significantly lower in the OSA group compare to control. Regression analysis showed RNFL thickness having significantly linear relationship with the AHI, specifically involving the superior and nasal quadrant.

Links between obstructive sleep apnea and glaucoma neurodegeneration

In the last few years, the possible link between obstructive sleep apnea (OSAS) and glaucoma, has attracted the interest of many scientists, especially in those forms of primary open angle glaucoma (POAG) and normal tension glaucoma (NTG), in which a progression of the disease occurs, even though intraocular pressure (IOP) is in the range of normality. The increased prevalence of POAG or NTG in patients affected by OSAS, and vice versa, has stimulated interest in the pathogenetic mechanisms that could trigger these two diseases. Hypoxia generated by apnea/hypopnea cycles has been identified as the main cause of many changes in the vascular and neurological systems, which alter the functioning not only of the optic nerve, but also of the whole organism. However, many other factors could be involved, like mechanical factors, obesity, hormonal imbalance and other sleep disorders. Furthermore, the demonstration of typical glaucomatous or glaucoma-like changes in the anatomy or function of the optic nerve and retinal nerve fiber layer by sensitive specific and diagnostic methods, such as perimetry, optical coherence tomography (OCT), optical coherence tomography angiography (OCTA) and electrophysiological exams keeps interest high for this field of study. For this reason, further investigations, hopefully a source of stronger scientific evidences, are needed.

Neuro-Ophthalmological Manifestations of Obstructive Sleep Apnea: Current Perspectives

Obstructive sleep apnea (OSA) is a disease of obstructed airways during sleep that significantly impacts the quality of life and increases the risk of various systemic diseases. OSA has been studied as a risk factor for a number of neuro-ophthalmic conditions and a strong relationship has been established with non-arteritic anterior ischemic optic neuropathy (NAION). The incidence of glaucoma and stroke have also been significantly associated with OSA and are conditions that may also be seen by neuro-ophthalmologists. Patients with NAION have a significantly higher incidence of OSA and OSA diagnosis significantly increases the risk for NAION development. Non-compliance with continuous positive airway pressure (CPAP) in OSA patients has also been found to be a risk factor for fellow-eye involvement and there is increasing evidence to suggest that every patient with NAION should be formally evaluated with polysomnography. The relationship between OSA and idiopathic intracranial hypertension (IIH) has also been studied, but the relationship between these two conditions is less clear. There is insufficient evidence to recommend routine eye examinations in OSA patients for papilledema and conducting a sleep study for a newly diagnosed IIH patient should be left to the discretion of the clinician based on other symptoms and risk factors of OSA.

Risk Factors for Fellow Eye Involvement in Nonarteritic Anterior Ischemic Optic Neuropathy

BACKGROUND

Nonarteritic anterior ischemic optic neuropathy (NAION) is the most common acute optic neuropathy in individuals older than 50 years. Demographic, ocular, and systemic risk factors for NAION have been identified, and we sought to determine which, if any, of these factors also increase risk of NAION in the fellow eye.

METHODS

We performed a retrospective chart review of patients with "ischemic optic neuropathy" (based on International Classification of Disease [ICD] codes) seen at a single eye center between 2007 and 2017. Patients who met diagnostic criteria for unilateral NAION without fellow eye optic neuropathy at diagnosis were included. Demographic information, ocular comorbidities, and systemic diagnoses were recorded, in addition to whether the fellow eye developed NAION during the follow-up period. Univariate and multivariate Cox proportional hazard regression were used to calculate hazard ratios (HRs) for fellow eye involvement.

RESULTS

Three hundred eighteen patients were identified by ICD codes, and 119 were included in the study. Twenty-nine (24%) patients developed NAION in the fellow eye over the mean follow-up period of 3.6 years (range: 1 month-11 years). Significant risk factors for fellow eye NAION included the presence of bilateral optic disc drusen (ODD, HR 2.78, 95% confidence interval [CI] 1.12-6.90, P = 0.02) and noncompliance with continuous positive airway pressure (CPAP) in patients with moderate-to-severe obstructive sleep apnea (HR 4.50, 95% CI 1.79-11.3, P = 0.0015).

CONCLUSIONS

Bilateral ODD and noncompliance with CPAP when indicated are associated with increased risk of NAION in the fellow eye. Patients with these risk factors should be counseled on the potentially devastating visual consequences of bilateral NAION, and compliance with CPAP should be stressed when appropriate.

Evaluation of effects of positive airway pressure treatment on retinal fiber thickness and visual pathways using optic coherence tomography and visual evoked potentials in the patients with severe obstructive sleep apnea syndrome

INTRODUCTION

Hypoxia during sleep in obstructive sleep apnea syndrome (OSAS) increases intracranial pressure, decreases cerebral perfusion pressure, and alters vascular supply to the optic nerve. Pattern visual evoked potential (pVEP) has revealed that it causes alterations in the optic nerve, and optic coherence tomography has shown that it causes alterations in the retinal and macular layers.

OBJECTIVES

To detect and compare possible alterations in macula and peripapillary retinal nerve fiber thickness (pRNFL) using OCT and in the optic nerve pathways using pVEP before and after positive airway pressure (PAP) in the patients with severe OSAS.

MATERIALS AND METHODS

Thirty patients who were diagnosed as having severe OSAS in the neurology-sleep outpatient clinic and 30 healthy control subjects were included in the study. Ophthalmic examinations were performed prior to (month 0) and after (month 6) PAP treatment, and pVEP (peak time [PT] and amplitude) and OCT parameters (peripapillary retinal-macular layers) were compared.

RESULTS

In the comparison between the severe OSAS (before treatment) and control groups, thinning was found in pRNFL (average, nasal, inferior) and in the macular layers (external and internal superior quadrants) (p < 0.05). pVEP investigation revealed increased PT in P100 and N145 waves and decreased amplitude of N75-P100 waves. In the comparisons before and after PAP treatment, a decrease in PT of N75 and P100 waves and increase in N75-P100 amplitudes were found. In the pRNFL, significant thickening was found in the layers with thinning before treatment, whereas no significant thickening was found in macular layers, except for the fovea.

DISCUSSION

It was shown that PAP treatment in patients with severe OSAS prevents hypoxia without causing alterations in intraocular pressure and thus reduces inflammation and causes thickening in the pRNFL and macular layers.

Screening for obstructive sleep apnea amongst patients with retinal vein occlusion

OBJECTIVE

To evaluate the prevalence and varying severity of obstructive sleep apnea (OSA) amongst those newly diagnosed with retinal vein occlusion (RVO), and screen patients with the use of 2 in-office-administered questionnaires validated against polysomnography.

DESIGN

Prospective cross-sectional study.

PARTICIPANTS

Consecutive adult patients (≥18 years of age) with a new diagnosis of RVO confirmed with intravenous fluorescein angiography were enrolled.

METHODS

The study was conducted at a tertiary academic centre between March 22, 2017, and April 7, 2018. Patients completed the Berlin and STOP-BANG questionnaires screening for OSA at presentation. Diagnostic test properties of the 2 questionnaires compared with polysomnography at a certified sleep laboratory centre as the gold standard for detection of OSA were calculated.

RESULTS

A total of 27 patients (37% females) with a mean (standard deviation) age of 69.6 (11.5) years completed the study. The diagnosis of OSA based on polysomnography was made in 96% (41% severe OSA) of patients with RVO. The Berlin questionnaire had a sensitivity of 43% (confidence interval [CI]: 22%-66%) and specificity of 67% (CI: 22%-96%). The STOP-BANG questionnaire had a sensitivity of 86% (CI: 64%-97%) and specificity of 50% (CI: 12%-88%).

CONCLUSIONS

Given the high prevalence of severe OSA amongst those with a new diagnosis of RVO, all patients should be strongly considered for polysomnography. The use of in-office questionnaires may aid in triaging urgency of referrals.

Update on obstructive sleep apnea for neuro-ophthalmology

PURPOSE OF REVIEW

Obstructive sleep apnea (OSA) is increasing in prevalence. The intermittent hypoxia of OSA has wide-ranging effects on a patient's general health outcomes. However, gold-standard investigations and treatment are expensive and a significant burden on patients. Therefore, OSA research remains focused on improving the means of diagnosing and treating OSA, in high-risk-associated conditions. This review is to provide an update on the advances in the field of OSA.

RECENT FINDINGS

There has been recent debate about the best practice for diagnosis and treatment of OSA. Further work has been done on conditions associated with OSA including hypertension, atherosclerosis, various types of dementia and intracranial aneurysms. Inflammatory and vascular risk factors associated with OSA increase stroke risk and alter outcomes for recovery. OSA should definitely be considered in patients presenting with nonarteritic anterior ischemic optic neuropathy, and perhaps those with intracranial hypertension.

SUMMARY

Newer home-based sleep-apnea testing can be implemented via physician clinics, with oversight by a certified sleep physician. Although continuous positive airway pressure (CPAP) is the gold-standard, management should include diet and exercise. It is important to test for, and treat OSA in patients with a range of neurological diseases. However, further studies into the long-term impact of CPAP on health outcomes are still needed.

Prevalence and Predictors of Ocular Complications in Obstructive Sleep Apnea Patients: A Cross-sectional Case-control Study

Purpose:

This study sought to identify the magnitude and the possible risk factors of ocular complications in patients with Obstructive Sleep Apnea (OSA).

Methods:

A hospital-based cross-sectional study with a nested case-control design was conducted. Qualifying study subjects were patients who had been diagnosed with moderate to severe OSA (AHI index of ≥ 5, n=80), and control subjects (n=20) who had an AHI index of ≤ 5 (“normal”). Study participants were recruited from Mansoura University Hospital’s Sleep Disorders Clinic in Mansoura, Egypt.Selected subjects were assessed for ocular complications at Mansoura Univerity Hospital Ophthalmic Center, (Mansoura), Egypt. An ophthalmic history was recorded, and opthalmic testing was carried out. The testing included unaided visual acuity measurement, refraction, best-corrected visual acuity measurement, slit lamp bio-microscopic evaluation of the anterior segment and anterior segment photography, dilated fundus examination, intraocular pressure measurement, fundus photo, and fluorescein angiography, and visual field assessment. Various tests of OSA symptoms were also monitored, including the AHI, lowest oxygen concentrations and desaturation index plus the overall severity index. .

Results:

It was found that OSA patients n=28 (35%), n=24 (30%), n=4 (5%) had senile cataract, normal tension glaucoma, and retinal ischemia, respectively, with an overall prevalence of 45%. Additionally, the OSA group had seven times greater risk (OR=7.36, 95%CI: 1.6-33.86) of vision-threatening disorders compared to the controls. OSA patients were observed to be at a greater risk of senile cataract 28 (35%), normal tension glaucoma 24 (30%), retinal ischemia 4 (5%) and conjunctival hyperemia and dry eye (OR=3.77, 95%CI: 1.02-13.95, OR=4.36, 95%CI: 1.26-17.08). Also, multivariate logistic regression analysis testing showed that the lowest oxygen saturation index was the only significant predictor negatively associated with vision-threatening disorders (OR=0.84, 95%CI: 0.75-0.93).

Conclusion:

The risk of vision-threatening and non-threatening ocular disorders is higher among OSA cases. The lowest oxygen saturation index was the only significant predictor of vision-threatening disorders. These findings support the recommendation that a full ophthalmic examination should be carried out on patients with confirmed OSA.

Correlation between structural progression in glaucoma and obstructive sleep apnea

BACKGROUND/OBJECTIVES

To investigate the correlation between obstructive sleep apnea (OSA) severity and the structural and functional progression in patients with glaucoma.

SUBJECTS/METHODS

This retrospective comparative cohort study included subjects from the polysomnography database in Chang Gung Memorial Hospital between June 1, 2009, and June 1, 2017, by identifying patients who had received diagnoses of primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), or glaucoma suspect. Patients with follow-up time of <3 years and/or <3 consecutive reliable optical coherence tomography (OCT) or visual field (VF) tests were excluded. Progression of overall peripapillary retinal nerve fiber layer (RNFL) thickness on OCT scans and VF mean deviation (MD) or VF index (VFI) were determined through linear regression trend analysis.

RESULTS

Thirty-two patients were included. There was a trend to higher percentage of progression on RNFL thickness and VF in higher OSAS severity. After stratifying patients to no OSA/mild OSA (group 1) and moderate/severe OSA (group 2), group 2 exhibited a significantly higher percentage of RNFL thickness progression than did group 1 (64.7% vs 26.7%, P = 0.042). Multivariate Cox regression analysis showed that severe OSA had an 8.448-fold higher risk of RNFL thickness progression after age, sex, diabetes mellitus, hypertension, hyperlipidemia, and body mass index adjustment (95% confidence interval, 1.464-48.752, P = 0.017).

CONCLUSIONS

Severe OSA is significantly correlated with a higher risk of structural deterioration in patients with glaucoma.

Nonarteritic anterior ischaemic optic neuropathy and its association with obstructive sleep apnoea: a health insurance database study

BACKGROUND

Nonarteritic anterior ischaemic optic neuropathy (NAION) is the most common acute optic neuropathy in old age. Although there are several known risk factors, the influence of obstructive sleep apnoea (OSA) has not been completely elucidated. The aim of this study was to evaluate the association between NAION and OSA.

METHODS

This retrospective, longitudinal cohort study used the national health insurance database of Taiwan covering the period 1996-2013. Patients without NAION at the diagnosis of OSA or who developed NAION 1 year after the diagnosis of OSA were enrolled. The patients were followed until death or the last day of the study. Cox proportional hazard regression was used to compute hazard ratios (HRs) and 95% confidence intervals (CIs) to investigate the association between OSA and NAION.

RESULTS

There were 8488 patients in the OSA group and 33 952 in the control group (without OSA), for a ratio of approximately 1:4. The percentages of NAION were 0.36% and 0.2% in the OSA and control groups, respectively, with a statistically significant difference (p < 0.01; chi-square test), and this significant difference remained in multivariate analysis (p = 0.019) with a significantly higher HR (1.66; 95% CI: 1.08-2.55). There was significant difference in the 30-39 years age group in multivariate analysis (p < 0.01, HR: 6.30; 95% CI: 2.28-17.40).

CONCLUSION

There was a strong association between NAION and OSA, and the patients with OSA had a higher risk of NAION. Further large-scale, prospective studies are warranted to evaluate the effect of OSA on developing NAION.

Obstructive sleep apnoea and increased risk of non-arteritic anterior ischaemic optic neuropathy

BACKGROUND/AIMS

To determine whether the development of non-arteritic anterior ischaemic optic neuropathy (NAION) is increased among patients newly diagnosed with obstructive sleep apnoea (OSA) in a large general population.

METHODS

A 12-year nationwide, population-based, retrospective cohort study including 1 025 340 beneficiaries in the 2002-2013 Korean National Health Insurance Service database was performed. We identified 919 patients newly diagnosed with OSA aged ≥40 years and matched 9190 non-OSA controls using estimated propensity scores in reference to age, sex, demographics, comorbidities and co-medications. We applied Kaplan-Meier curves and Cox proportional hazard models to determine the risk of developing NAION in the OSA group compared with the non-OSA group.

RESULTS

The 10-year incidence probability of NAION was higher in the OSA group (0.92%; 95% CI 0.88 to 0.97) than the non-OSA group (0.42%; 95% CI 0.41 to 0.44, p=0.002, log-rank test). The OSA group was at increased risk of developing NAION compared with the non-OSA group (HR 3.80; 95% CI 1.46 to 9.90) after adjusting for demographics, comorbidities and co-medications.

CONCLUSIONS

Our results suggest that patients with newly diagnosed OSA have an increased risk of NAION, although the absolute risk of NAION is low.

Association between obstructive sleep apnea and optic neuropathy: a Taiwanese population-based cohort study

PURPOSE

Obstructive sleep apnea (OSA) is associated with many systemic diseases including diabetes, hypertension, stroke, and cardiovascular disease. The aim of our study was to investigate the association between OSA and optic neuropathy (ON), and to evaluate the efficacy of treatment for OSA on the risk of ON.

METHODS

We used the data from the Longitudinal Health Insurance Database, which involved one million insurants from Taiwan National Health Insurance program (Taiwan NHI).

RESULTS

OSA patients had a 1.95-fold higher risk of ON compared with non-OSA patients in all age group. The risk was significantly higher (adjusted hazard ratio: 4.21) in the group aged <45 years and male individuals (adjusted hazard ratio: 1.93). Meanwhile, sleep apnea was associated with ON regardless of the existence of comorbidity or not. OSA patients treated with continuous positive airway pressure (CPAP) had an adjusted 2.31-fold higher hazard of developing ON compared to controls, and those without any treatment had an adjusted 1.82-fold higher hazard of developing ON compared to controls. Moreover, ON patients had a 1.45-fold higher risk of OSA, and those aged between 45 and 64 years (hazard ratio: 1.76) and male individuals (hazard ratio: 1.55) had highest risk.

CONCLUSIONS

Our study showed that OSA increased the risk of developing ON after controlling the comorbidities; however, treatment with CPAP did not reduce the risk of ON. Further large population study accessing to medical records about the severity of OSA and treatment for OSA is needed to clarify the efficacy of treatment for OSA in reducing the risk of ON.

Prevalence and risk factors of eye diseases in adult patients with obstructive sleep apnoea: results from the SLE.E.P.Y cohort study

OBJECTIVES

To assess the occurrence of glaucoma, eyelid, corneal and macular disorders in a cohort of patients with obstructive sleep apnoea (OSA) diagnosed by overnight polysomnography and to investigate into the risk factors for the above eye diseases (EDs).

DESIGN

Cross-sectional cohort study between 2014 and 2015.

SETTING

Unit of Respiratory Medicine and Eye Clinic of the University of Verona.

PARTICIPANTS

431 consecutive patients were considered eligible. Of these, 87 declined to participate, 35 were untraceable and 13 were deceased.

INTERVENTIONS

A complete ophthalmic evaluation of both eyes for each patient.

PRIMARY AND SECONDARY OUTCOME MEASURES

Best-corrected distance visual acuity, intraocular pressure, corneal, macular and optic nerve optical coherence tomography, ocular aberrometry, optic nerve laser polarimetry, visual field test, and eyelid examination.

RESULTS

296 patients aged 64.5±12.8 years, 23% female and 77% male, underwent ophthalmic examination. There was 56% (n=166) prevalence of eyelid disorders, 27% (n=80) of corneal disorders, 13% (n=39) of macular disorders and 11% (n=33) of glaucoma. Advancing age was not associated with the severity of OSA, while significant differences were found for gender, body mass index, Oxygen Desaturation Index, smoking habit, hypertension and diabetes. Severe OSA was significantly associated with glaucoma (OR, 95% CI 1.05 to 5.93, p=0.037).

CONCLUSIONS

EDs were more prevalent in our patinets with OSA than in the general population. Severe Apnoea/Hypopnoea Index level seemed to play a role as risk factor only for glaucoma.

Diseases of the retina and the optic nerve associated with obstructive sleep apnea

Many associations between ocular disorders and obstructive sleep apnea (OSA) have been studied, such as nonarteritic anterior ischemic optic neuropathy, glaucoma, papilledema, retinal vein occlusion, eyelid hyperlaxity, lower-eyelid ectropion and recurrent corneal erosions. The objective of this review is to synthetize the possible vascular disorders of the retina and the optic nerve associated with sleep apnea patients and to discuss the underlying pathophysiological hypotheses. Main mechanisms involved in the ocular complications of OSA are related to intermittent hypoxia, sympathetic system activation, oxidant stress, and deleterious effects of endothelin 1. The main evidence-based medicine data suggest that OSA should be screened in patients with ischemic optic neuropathy and diabetic retinopathy. The effect of OSA treatment and emerging therapies are discussed.

Diurnal changes in retinal nerve fiber layer thickness with obstructive sleep apnea/hypopnea syndrome

AIM

To compare the retinal nerve fiber layer (RNFL) thickness in the morning and evening in Thai patients with varying degrees of obstructive sleep apnea/hypopnea syndrome (OSAHS).

METHODS

In this cross-sectional study, potential OSAHS patients at Siriraj Hospital underwent polysomnography to determine the severity of OSAHS and an eye examination (including best corrected visual acuity, slit-lamp examination, and Goldmann applanation tonometry). RNFL thickness was recorded once in the morning and once in the evening, using spectral domain optical coherence tomography. Thickness was expressed as an average and given for each quadrant. Patients with ocular or systemic diseases that might affect RNFL thickness were excluded.

RESULTS

Forty-one eyes of 41 patients were classified into 4 OSAHS groups. The average and mean RNFL thickness in most of the four quadrants of the severe OSAHS group trended toward being less than those in the comparable quadrants of the other groups in both the morning and evening. In the moderate OSAHS group, the average RNFL thickness and temporal and superior quadrant thickness in the morning were significantly higher than in the evening (P=0.01, P=0.01, and P=0.03, respectively). In the severe OSAHS group, the inferior quadrant thickness in the morning was significantly higher than in the evening (P=0.03).

CONCLUSION

The RNFL thickness in the morning was higher than in the evening in moderate OSAHS.

The association between ophthalmologic diseases and obstructive sleep apnea: a systematic review and meta-analysis

PURPOSE

The purpose of this study was to evaluate the association between obstructive sleep apnea (OSA) and ophthalmologic diseases, specifically glaucoma, nonarteritic anterior ischemic optic neuropathy (NAION), retinal vein occlusion (RVO), central serous chorioretinopathy (CSR), and floppy eyelid syndrome (FES), by performing a systematic review and meta-analysis of published studies.

METHODS

PubMed, Embase, and Scopus databases were searched for observational studies on OSA and its association with select ophthalmologic diseases. Data was pooled for random-effects modeling. The association between OSA and ophthalmologic diseases was summarized using an estimated pooled odds ratio with a 95 % confidence interval.

RESULTS

Relative to non-OSA subjects, OSA subjects have increased odds of diagnosis with glaucoma (pooled odds ratio (OR) = 1.242; P < 0.001) and floppy eyelids syndrome (pooled OR = 4.157; P < 0.001). In reverse, the overall pooled OR for OSA was 1.746 (P = 0.002) in the glaucoma group, 3.126 (P = 0.000) in the NAION group, and 2.019 (P = 0.028) in the CSR group. For RVO, one study with 5965 OSA patients and 29,669 controls demonstrated a 1.94-fold odds increase in OSA patients.

CONCLUSIONS

Our results suggest significant associations between OSA and glaucoma, NAION, CSR, and FES. Screening for OSA should be considered in patients with glaucoma, NAION, CSR, or FES.

Choroidal thickness changes in obstructive sleep apnea syndrome: a systematic review and meta-analysis

PURPOSE

Obstructive sleep apnea syndrome (OSAS) is a common chronic disorder associated with hypoxia and endothelial and vascular dysfunction. Many studies have analyzed choroidal thickness measurements in patients with different severities of OSAS versus normal subjects by optical coherence tomography (OCT), but the results have been inconsistent. Therefore, a meta-analysis was performed to evaluate the choroidal thickness changes in OSAS measured by OCT.

METHODS

Pertinent studies were retrieved by a comprehensive search of PubMed, Embase, Web of Science, and the Cochrane Library from inception to August 2015. For continuous outcomes, the weighted mean difference (WMD) and 95 % confidence interval (CI) were calculated by using a random effects model.

RESULTS

Seven case-control studies were included in the final meta-analysis, containing a total of 784 eyes (558 in the OSAS group and 226 in normal controls). The results showed that subfoveal choroidal thickness (SFCT) was significantly reduced compared with normal controls, with pooled WMD -8.06 (95 % CI -15.72 to -0.41) for mild OSAS, -29.99 (95 % CI -52.40 to -7.58) for moderate OSAS, and -53.72 (95 % CI -88.95 to -18.48) for severe OSAS. Choroidal thickness at 1 mm temporal to the fovea and at 1 mm nasal to the fovea were also significantly lower than those in the normal controls (WMD = -28.94, 95 % CI -43.78 to -14.10 and WMD = -20.90, 95 % CI -36.62 to -5.18).

CONCLUSION

This meta-analysis suggests that choroidal thickness was reduced in OSAS. Considering the non-invasive nature of OCT, OCT could be a useful tool for grading the severity of OSAS.

The Association Between Obstructive Sleep Apnea and Nonarteritic Anterior Ischemic Optic Neuropathy: A Systematic Review and Meta-Analysis

PURPOSE

Nonarteritic anterior ischemic optic neuropathy (NAION) is a multifactorial disease, and recently epidemiologic studies have investigated the association between obstructive sleep apnea (OSA) and NAION. A systematic review of the association of OSA and NAION has not been performed. Therefore, the current meta-analysis was performed to assess such potential association between OSA and risk of NAION.

METHODS

A systematic search of PubMed and EMBASE databases was performed for published studies evaluating the association between OSA and NAION. The summary odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for categorical risk estimates. Sensitivity analyses and subgroup analyses were also performed to assess the robustness of pooled outcomes.

RESULTS

A total of four prospective cohort studies and one case-control study met our inclusion criteria. The pooled OR of developing NAION in the subjects with OSA was 6.18 (95% CI, 2.00-19.11) versus non-OSA controls. Sensitivity analyses showed that no matter one study excluded, the pooled OR did not change significantly, which indicated that the evidence was robust. In subgroup analyses, a significant association was seen in studies matched systemic risk factors (OR, 5.00; 95% CI, 2.22-11.25), but not in those non-matched. The magnitude and direction of effects were also affected by methodological variability, including study design, and diagnosis of OSA.

CONCLUSIONS

The findings from this meta-analysis supported the robust evidence that OSA was a strong independent risk factor of NAION. Relative to non-OSA controls, the subjects with OSA were found to have a more than sixfold risk of NAION. In future, more well-designed studies are needed to confirm these findings.

Neuro-Ophthalmology Annual Review

PURPOSE

The purpose of this review was to update the practicing ophthalmologist on the English language neuro-ophthalmology literature from the past year.

DESIGN

A review of English language literature from August 1, 2013, to August 1, 2014, was conducted.

METHODS

The author searched PubMed from August 1, 2013, to August 1, 2014, limited to English language publications including original articles, review articles, and case reports and excluding letters to the editor, unpublished work, and abstracts. The following topics were searched: pupillary abnormalities, eye movement dysfunction, neuromuscular diseases, optic neuropathies, optic neuritis, demyelinating diseases including multiple sclerosis, lesions of the optic chiasm and posterior primary visual pathways, elevated intracranial pressure, tumors and aneurysms affecting the visual pathways, vascular diseases, higher visual function, and neuroimaging advances. The focus of this review is on clinically relevant literature in the past year for the practicing ophthalmologist. The aim was to highlight remarkable and interesting literature rather than exhaustively including all new neuro-ophthalmological publications of the year.

RESULTS

Initially, more than 11,000 articles were identified. One hundred were selected that met criteria specified above.

CONCLUSIONS

This review updates the comprehensive ophthalmologist on neuro-ophthalmic topics.

Poor responders to bevacizumab pharmacotherapy in age-related macular degeneration and in diabetic macular edema demonstrate increased risk for obstructive sleep apnea

PURPOSE

To investigate the risk for obstructive sleep apnea (OSA) in patients with exudative age-related macular degeneration (AMD) or diabetic macular edema with poor response to anti-vascular endothelial growth factor therapy with bevacizumab (Avastin).

METHODS

Age-related macular degeneration group was categorized into nonexudative, exudative, or poor response exudative. Diabetic macular edema group included patients with nonproliferative diabetic retinopathy and cystoid macular edema. Patients were categorized based on the number of intravitreal injections of bevacizumab received. Both groups were compared with age-matched controls. Patients completed a screening questionnaire to assess the risk for OSA, the main outcome measure.

RESULTS

Of 103 patients with AMD, 56 (54.37%) had nonexudative AMD and 47 (45.63%) had exudative AMD, of which 14 (29.79%) had poor response exudative AMD and were at a significantly higher risk of OSA (P < 0.05). Of 30 diabetic macular edema patients with cystoid macular edema, 4 (19%) received 1 injection, 18 (81.82%) received 2 or more consecutive injections, and 16 (72.73%) received 3 or more consecutive injections. Risk for OSA increased significantly with increasing number of injections (P < 0.05).

CONCLUSION

Patients with exudative AMD and diabetic macular edema with poor response to anti-vascular endothelial growth factor therapy have a significantly higher risk of OSA compared with age-matched controls and should be screened to assess the risk of OSA.

Association between glaucoma and obstructive sleep apnea syndrome: a meta-analysis and systematic review

Background

Obstructive sleep apnea syndrome (OSAS) is a common disease that increases the risk of diabetes, heart disease, and stroke. However, studies of an association between OSAS and glaucoma neuropathy have reported controversial findings.

Objective

The main purpose of this study was to evaluate whether a significant association exists between OSAS and glaucoma by performing a meta-analysis of previous studies.

Methods

A comprehensive literature search using the PubMed and Embase databases was performed to identify cross-sectional, case-control, and cohort studies related to the topic. We estimated a pooled odds ratio (OR) for the association between OSAS and glaucoma, by a fixed- or random-effects model.

Results

In total, 16 studies with 2,278,832 participants met the inclusion criteria: one retrospective cohort study reported an adjusted hazard ratio of glaucoma of 1.67 (95% CI = 1.30–2.17). Using a fixed-effects model, the pooled OR of six case-control studies was 1.96 (95% CI = 1.37 2.80). A significant association was also identified in a meta-analysis of nine cross-sectional studies using a random-effects model, which showed a pooled OR of 1.41 (95% CI = 1.11 1.79). However, the reported pooled estimates for case control studies and cross-sectional studies were based on unadjusted ORs.

Conclusions

Our results suggest that OSAS is associated with the prevalence of glaucoma. However, this result was based only on unadjusted estimates. Prospective cohort studies designed to take into consideration potential confounders, or examination of data from interventional trials to determine whether a reduction in OSAS status is associated with a reduced incidence of glaucoma, are needed to clarify whether OSAS is an independent risk factor for glaucoma.

Obstructive sleep apnea and optic neuropathy: is there a link?

Over the last decade, there has been an emerging interest in the link between obstructive sleep apnea (OSA) and ocular health. Though the evidence for OSA playing a role in cerebrovascular disease risk seems clear, the same cannot be said for optic neuropathies. The association between OSA and glaucoma or non-arteritic anterior ischemic optic neuropathy (NAION) has been postulated to be secondary to direct hypoxia or mechanisms of optic nerve head vascular dysregulation. Papilledema and increased intracranial pressure have also been reported in OSA and are thought to be due to increased cerebral perfusion pressure and cerebral venous dilation secondary to hypoxia and hypercapnia. This article reviews the evidence for possible pathophysiological links between OSA and optic nerve pathology. The epidemiologic and clinical evidence for an association, direct or indirect, between OSA and glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), and papilledema or idiopathic intracranial hypertension is presented.

Current concepts in the diagnosis, pathogenesis and management of nonarteritic anterior ischaemic optic neuropathy

Nonarteritic anterior ischaemic optic neuropathy (NAION) is the most common acute optic neuropathy in patients over the age of 50 and is the second most common cause of permanent optic nerve-related visual loss in adults after glaucoma. Patients typically present with acute, painless, unilateral loss of vision associated with a variable visual field defect, a relative afferent pupillary defect, a swollen, hyperaemic optic disc, and one or more flame-shaped peripapillary retinal haemorrhages. The pathogenesis of this condition is unknown, but it occurs primarily in patients with structurally small optic discs that have little or no cup and a variety of underlying vascular disorders that may or may not be known at the time of visual loss. There is no consistently beneficial medical or surgical treatment for the condition, but there are now animal models that allow testing of various potential therapies. About 40% of patients experience spontaneous improvement in visual acuity. Patients in whom NAION occurs in one eye have a 15-19% risk of developing a similar event in the opposite eye over the subsequent 5 years.

Neuro-Ophthalmology Annual Review

The aim of this study was to update the practicing ophthalmologist on the English-language neuro-ophthalmology literature from the prior year. This study is a review of English-language literature from August 1, 2012, to August 1, 2013. The authors searched PubMed articles published from August 1, 2012, to August 1, 2013, limited to English-language publications including original articles, review articles, and case reports and excluding letters to the editor, unpublished work, and abstracts. We researched the following topics: pupillary abnormalities, eye movement dysfunction, neuromuscular diseases, optic neuropathies, optic neuritis and demyelinating disease including multiple sclerosis, lesions of the chiasm and posterior primary visual pathways, elevated intracranial pressure, tumors and aneurysms affecting the visual pathways, vascular diseases, higher visual functions, and neuroimaging advances. We intend to share clinically relevant literature of the past year with the practicing ophthalmologist. We aimed to highlight remarkable and interesting literature rather than exhaustively including all new neuro-ophthalmological publications of the year. We reviewed literature in the past year with a focus on relevance and novelty. This review updates the comprehensive ophthalmologist on neuro-ophthalmic topics.