Young Adults With Anterior Ischemic Optic Neuropathy: A Multicenter Optic Disc Drusen Study

Advances in origin, evolution, and pathogenesis of optic disc drusen: A narrative review

Optic disc drusen (ODD) is acellular calcified deposits found mainly in front of the lamina cribrosa within the optic nerve. It can cause chronic or acute vision loss. There has been progress in clinical diagnosis using ophthalmic multimodal imaging in recent years. We conducted a database search on PubMed and Google Scholar (April 2023) with no restrictions on publication year or language. We used the terms: ("optic disc drusen") OR ("optic nerve head drusen") OR ("drusen of optic nerve head"). Other terms included gene, mutation, scleral canal, axonal transport, calcinosis, mitochondria, blood vessel, vasculature, visual field, vision, and optical coherence tomography to identify publications. Etiologically, ODD may stem from congenital genetic defects, aberrant axoplasmic transport, anatomical abnormalities, and mechanical factors during ocular duction. Clinically, ODD is linked to progressive visual field defects and vascular complications. Detection of deeply buried ODD can be challenging, but advances in optical coherence tomography make early identification possible. Structural changes, including retinal nerve fiber layer thinning, can be monitored. Increasing reports indicate vascular complications, including anterior ischemic optic neuropathy, in ODD patients. Currently, ODD-related visual field defects are not effectively treated, and observation remains the primary management approach. Future pathological discoveries or the establishment of animal models may provide new evidence for revealing the pathogenesis of ODD.

Characterization of Peripapillary Hyperreflective Ovoid Mass-like Structures in a Broad Spectrum of Neurologic Disorders

PURPOSE

Peripapillary hyperreflective ovoid mass-like structures (PHOMSs) have been identified in ophthalmic and neurologic diseases. Because PHOMSs were found more frequently in these cohorts compared with healthy control participants, it is assumed that the presence of PHOMSs reflects a secondary disease marker of unknown significance. The extent to which disease-specific differences are reflected in PHOMSs has not yet been investigated sufficiently.

DESIGN

Monocentric, retrospective study.

PARTICIPANTS

We analyzed a large cohort of people with a broad spectrum of neurologic disorders, including neuroimmunologic diseases (NIDs; n = 237), epilepsy (n = 153), movement disorders (MDs; n = 44), intracranial hypertension (IH; n = 13), and inborn errors of metabolism (n = 90).

METHODS

We analyzed the prevalence, location, volume, and intensity of PHOMSs. Peripapillary hyperreflective ovoid mass-like structure volumes were correlated with demographic and other OCT parameters.

MAIN OUTCOME MEASURES

Prevalence, location, volume, and intensity of PHOMSs.

RESULTS

We identified PHOMSs in 7% of the analyzed eyes. Peripapillary hyperreflective ovoid mass-like structures were detected in all cohorts, and their location was predominantly nasal. The median volume of all PHOMSs was 0.06 mm3. However, the median PHOMS volume was increased in those with IH compared with those with NID (P = 0.009), epilepsy (P = 0.038), or MDs (P = 0.027). The PHOMS volume correlated positively with the opening of the Bruch membrane and correlated negatively with the age of the cohort after the exclusion of patients with IH. Overall, PHOMS intensity was comparable with that of the optic nerve.

CONCLUSIONS

Because larger PHOMS volumes were found in individuals with IH, a mechanistic link to increased intracranial pressure can be assumed. It remains unclear whether this explanation also applies to individuals with other neurologic disorders with PHOMSs. Because PHOMSs have a relevant influence on OCT parameters, their presence also should be considered in nonophthalmic scientific studies in the future.

FINANCIAL DISCLOSURE(S)

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

Association between Semaglutide and Nonarteritic Anterior Ischemic Optic Neuropathy: A Multinational Population-Based Study

PURPOSE

To investigate whether semaglutide increases the risk of nonarteritic anterior ischemic optic neuropathy (NAION) in the general population.

DESIGN

This retrospective cohort study used a deidentified global electronic medical records database. The enrollment period was extended from January 2017 to August 2023, with observations concluding in August 2024.

PARTICIPANTS

This study included individuals with type 2 diabetes mellitus (T2DM) or obesity. They were further categorized into T2DM-only, obesity-only, and T2DM with obesity groups to assess the differences among these subgroups. The effects of semaglutide were compared with those of glucose-lowering or weight-loss medications other than glucagon-like peptide receptor agonists.

METHODS

Patient data were obtained from 160 health care organizations across 21 countries. Outcomes were evaluated at 1, 2, and 3 years of follow-up. A 1:1 propensity score matching was performed to balance age, sex, body mass index, hemoglobin A1C, medications, and underlying comorbidities. Cox regression models were used to compute hazard ratios (HRs) and 95% confidence intervals (CIs).

MAIN OUTCOME MEASURES

The occurrence of NAION.

RESULTS

The final analysis included 37 314 participants with T2DM only, 129 690 participants with obesity only, and 130 216 participants with both T2DM and obesity. The results indicated that the administration of semaglutide was not associated with the development of NAION in the T2DM-only group (1-year follow-up: HR, 2.32; 95% CI, 0.60-8.97; 2 years: HR, 2.31; 95% CI, 0.86-6.17; 3 years: HR, 1.51; 95% CI, 0.71-3.25), the obesity-only group (1-year follow-up: HR, 0.41; 95% CI, 0.08-2.09; 2 years: HR, 0.67; 95% CI, 0.20-2.24; 3 years: HR, 0.72; 95% CI, 0.24-2.16), and the T2DM with obesity group (1 year follow-up: HR, 0.81; 95% CI, 0.42-1.57; 2 years: HR, 1.2; 95% CI, 0.74-1.94; 3 years: HR, 1.19; 95% CI, 0.78-1.82).

CONCLUSIONS

The findings suggest that semaglutide may not be associated with an increased risk of NAION in the general population. Therefore, avoidance of semaglutide based solely on concerns regarding the risk of NAION may not be warranted because its potential benefits for blood glucose control and cardiovascular health likely outweigh its potential risks.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Whole genome sequencing of 10 families with optic disc drusen

INTRODUCTION

Optic disc drusen (ODD) are believed to have a genetic predisposition, with autosomal dominant inheritance pattern with incomplete penetrance suggested through family pedigree analysis. ODD prevalence is higher in certain genetic disorders, such as pseudoxanthoma elasticum and retinitis pigmentosa. This study aimed to identify candidate genes potentially involved in the development of ODD.

METHODS

Family members aged 18 years or older from families with ODD were included. Participants underwent optical coherence tomography of the optic nerve head, and blood samples were collected for whole-genome sequencing using the Illumina NovaSeq 6000 platform. Single nucleotide variants were identified with the Genome Analysis Toolkit (GATK) and filtered in VarSeq using a population frequency threshold of 1%. Selected genes were classified according to ACMG guidelines.

RESULTS

A total of 10 families were included, three of which had more than two affected members. Thirty-three variants were identified, with the following genes selected for description: ABCC6, DDX50, TREX1, PLCB4, PTPRQ, LBR, RP1L1, and KRT3. The identified candidate genes showed a wide range of functions and are associated with different disorders. Of particular interest is ABCC6, which normally inhibits ectopic calcification.

CONCLUSION

We identified a list of candidate genes. Studies including larger ODD families are necessary to identify robust candidate genes.

Peripapillary hyperreflective ovoid mass-like structure (PHOMS) and optic disc drusen in pediatric pseudo-papilledema

PURPOSE

Diagnosing pseudo-papilloedema (PPO) in children presents challenges and may lead to invasive investigations, with optic disc drusen (ODD) being the most common etiology. Other specific causes include tilted disc, optic neuritis, tumoral infiltration, vitreo-papillary traction, and Leber hereditary optic neuropathy. Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are frequently observed in these cases, yet their pathophysiology remains unexplained, particularly their relation to ODD, which is still debated. Here, we explored whether patients with PPO associated with ODD, or seemingly isolated cases, could exhibit PHOMS without ODD or ODD without PHOMS, and how this might affect retinal nerve fiber layer (RNFL) thickness.

METHODS

In this two-centre retrospective observational study, we included patients under 20 years old presenting with PPO without specific causes, with a subgroup followed for at least one year. Enhanced depth imaging optical coherence tomography was used to assess the presence and evolution of PHOMS and ODD, as well as RNFL thickness.

RESULTS

We included twenty-seven patients, with thirteen followed for at least one year. In all eyes, we observed concomitant PHOMS and either deep or superficial ODD. RNFL thickness was increased in patients with deep ODD and decreased in those with superficial ODD, which was observed during follow-up.

CONCLUSIONS

ODD and PHOMS are concomitant features present in patients with PPO. PHOMS sometimes serve as indicators, as buried ODD are challenging to identify in young children. However, ODD tend to become more superficial over time, while RNFL thickness decreases.

KEY MESSAGES

WHAT IS KNOWN : Diagnosing the cause of pseudo-papilledema (PPO) in children is challenging and often requires invasive investigations. The relationship between optic disc drusen (ODD) and peripapillary hyperreflective ovoid mass-like structures (PHOMS) in the context of PPO remains poorly understood.

WHAT IS NEW

PHOMS and ODD seem to consistently co-occur in pediatric PPO cases where no other specific causes are identified. Retinal nerve fiber layer (RNFL) thickness increases in the presence of deep ODD and decreases as ODD become more superficial with age. RNFL thinning progresses in correlation with the patient's age.

Anterior ischemic optic neuropathy in patients treated with semaglutide: report of four cases with a possible association

BACKGROUND

Semaglutide, a glucagon-like peptide-1 receptor agonist, is increasingly used worldwide for its cardiometabolic benefits. However, it has recently been associated with nonarteritic anterior ischemic optic neuropathy (NAION). This report presents four clinical cases and explores a possible association.

CASE PRESENTATION

Four male patients were diagnosed with NAION during semaglutide treatment, with treatment durations of less than one year in three cases. All presented with significant optic disc edema and intraretinal fluid on optical coherence tomography, along with crowded optic disc and small Bruch's membrane opening diameters (< 1.4 mm in three cases). One patient exhibited optic disc drusen. Visual field defects corresponded with ganglion cell layer atrophy on optical coherence tomography. Systemic risk factors varied; two patients had only obesity.

CONCLUSIONS

Our observation suggests that individuals with small Bruch's membrane opening diameter may be at risk of developing NAION during semaglutide treatment.

Combining Paracentral Acute Middle Maculopathy and Peripapillary Fluid as Biomarkers in Anterior Ischemic Optic Neuropathy

PURPOSE

To determine if paracentral acute middle maculopathy (PAMM) and peripapillary intraretinal and subretinal fluid (IRF/SRF) could help distinguish between arteritic anterior ischemic optic neuropathy (A-AION) and nonarteritic AION (NA-AION) at an early stage.

DESIGN

Nested prospective cross-sectional diagnostic accuracy study.

METHODS

This study used single-center optical coherence tomography (OCT) data from 8 patients with A-AION and 24 patients with NA-AION from two prospective cross-sectional studies with consecutive sampling (ClinicalTrials.gov: NCT05248906 and NCT05305079). The diagnosis of A-AION was based on expert interpretation of biochemical markers of inflammation, temporal artery biopsy and positron emission tomography/computed tomography. The diagnosis of NA-AION was made in cases without suspicion or clinical evidence of A-AION and with confirmed neuroophthalmological expert diagnosis. For this substudy patients were also required to have an OCT scan in relation to the diagnosis of AION. Macular OCT scans were graded by two independent, masked graders for the presence of PAMM and for IRF/SRF. The extension of IRF/SRF was assessed using an Early Treatment Diabetic Retinopathy Study (ETDRS) grid.

RESULTS

PAMM was found in 50% of patients with A-AION and in 0% of patients with NA-AION (P = .0019). In the setting of AION, the sensitivity of PAMM for the diagnosis of A-AION was 50% (95% CI: 16%-84%) while the specificity was 100% (95% CI: 86%-100%). Conversely, peripapillary IRF/SRF with extension into the ETDRS grid was observed in 83% of patients with NA-AION but in 0% of patients with A-AION (P = .000047). The sensitivity of central macula-involving IRF/SRF for the diagnosis of NA-AION was 83% (95% CI: 63%-95%), while the specificity was 100% (95% CI: 63%-100%). Combining the two biomarkers, 75% of patients with AION could be classified based on OCT alone.

CONCLUSION

PAMM appears to be a biomarker of A-AION while extensive peripapillary fluid appears to be a biomarker of NA-AION. Combining OCT biomarkers might allow for early classification of AION and warrants further prospective studies.

Optic Disc Drusen Prevalence in Patients With Retinitis Pigmentosa: A Cross-Sectional Study

BACKGROUND

Studies of patients with retinitis pigmentosa (RP) have reported an increased prevalence of optic disc drusen (ODD) compared with the ODD prevalence in the general population. The diagnostic gold standard method for identifying ODD is enhanced depth imaging optical coherence tomography (EDI-OCT), but this modality has not previously been used systematically for identifying ODD in patients with RP. This study aimed to estimate the prevalence of ODD in patients with RP using EDI-OCT.

METHODS

In this cross-sectional study, 40 patients with clinically diagnosed RP aged 18 years or older were included. All patients underwent an ophthalmic examination, including kinetic perimetry, EDI-OCT of the optic nerve head, and fundus photography. Genetic testing with a next-generation sequencing panel of retinal dystrophy genes was performed on the RP patients without a prior genetic diagnosis.

RESULTS

Twelve patients (30.0%) had at least one ODD. Six patients had bilateral ODD. No significant differences between patients with and without ODD were found according to age, refraction, best-corrected visual acuity, Bruch membrane opening, or visual field. The genetic variation causing RP was found in 11 of 12 cases in the ODD group and in 17 of 28 cases in the group without ODD.

CONCLUSIONS

We found the prevalence of ODD in patients with RP to be 30.0%. This is 15 times higher than in the general population and much higher than previously estimated in most studies, potentially indicating that the 2 conditions might be pathogenically related.

Evaluation and management of nonarteritic anterior ischemic optic neuropathy: a national survey

PURPOSE

The evaluation and management of Nonarteritic Anterior Ischemic Optic Neuropathy (NAION) lacks standardized guidelines. This study aimed to investigate the real-world practices of neuro-ophthalmologists in the evaluation and management of typical NAION cases.

METHODS

A national survey, conducted between 2019 and 2021, involved all practicing neuro-ophthalmologists. A structured questionnaire assessed their approach to risk factor evaluation and treatment of NAION, with 19 questions about risk factors and six questions concerning treatment and prevention of fellow-eye involvement.

RESULTS

Thirty-six out of 37 neuro-ophthalmologists participated. Most physicians referred patients for evaluation of the following risk factors: obstructive sleep apnea (83.3%), diabetes mellitus (83.3%), hypertension (77.7%), dyslipidemia (72.2%), and optic disc drusen (38.8%). However, there was considerable variation in the choice of diagnostic tests recommended. Furthermore, nearly 47% recommended an embolism workup. Regarding treatment, the majority (91%) did not recommend routine treatment for NAION, although in 16.7%, high-dose corticosteroids were occasionally prescribed. Secondary prevention with aspirin (80.6%), smoking cessation advice (86.1%), and advising against erectile dysfunction medications for men (80.6%) were common recommendations.

CONCLUSION

While the risk factors associated with NAION are well-reported, there is a lack of uniformity on which tests should be ordered to evaluate these risk factors. Most neuro-ophthalmologists concur that routine treatment for NAION is not warranted, but not unanimously. Future studies to develop a consensus guideline for post-NAION work-up and management recommendations may assist in the detection and management of preventable risk factors.

Optic disc drusen: Dystrophic calcification, a potential target for treatment

Optic disc drusen (ODD) are calcified, acellular bodies, seen in the optic nerve head of up to 2% of the population. Although seldomly affecting visual acuity, visual field defects are common, and severe, ischemic complications causing irreversible vision loss are known to occur. Different treatment strategies for ODD have been explored, but so far without success. This review focuses on the unique, calcified property of ODD, describing what we know about ODD pathogenesis and previously tried treatment strategies. In this context, we discuss current knowledge about calcium and pathological calcifications, including intracranial and ocular calcifications. We also explore some of the obstacles that must be addressed to develop a therapy centred on the concept of calcification, should calcification be identified as a pathogenic factor contributing to vision loss.

Validation of retinal oximetry vessel selection using fluorescein angiography in patients with optic disc drusen

Retinal oximetry could provide insights into the pathophysiology of optic nerve disease, including optic disc drusen (ODD). Vessel selection for oximetry analysis is based on morphological characteristics of arterioles and venules and supported by an overlay of estimated blood oxygen saturations. The purpose of this cross-sectional study was to determine the validity of this vessel selection procedure by comparing it with vessel selection supported by video fluorescein angiography (FA). The study included 36 eyes of 36 patients with ODD who underwent retinal oximetry (Oxymap retinal oximeter T1) followed by FA (Heidelberg Spectralis). Two trained graders selected vessel segments in a pre-defined measurement area around the optic disc. One of these graders additionally performed the vessel segment selection with the support of FA images. When performed by the same grader, FA-supported and non-FA-supported vessel selection did not lead to significant differences in total vessel segment length, estimated oxygen saturations or vessel diameters (all p > 0.05). Inter-grader differences were found for arterial and venous segment lengths and arterial saturation (p < 0.05). A similar tendency was found for the arteriovenous saturation difference (p = 0.10). In conclusion, identifying vessel segments for retinal oximetry analysis based on vessel morphology and supported by a color-coded saturation overlay appears to be a valid method without the need for invasive angiography. A numerically small inter-grader variation may influence oximetry results. Further studies of retinal oximetry in ODD are warranted.

Peripapillary hyperreflective ovoid mass-like structures: multimodal imaging and associated diseases

Growing evidence has demonstrated that peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel structures rather than a subtype of optic disc drusen. They correspond to the laterally bulging herniation of optic nerve fibers and are believed to be the marker of axoplasmic stasis. PHOMS present in a broad spectrum of diseases, including optic disc drusen, tilted disc syndrome, papilloedema, multiple sclerosis, non-arteritic anterior ischemic optic neuropathy, optic neuritis, Leber hereditary optic neuropathy, and so on. We focus on the multimodal imaging features, pathophysiological mechanisms of PHOMS, and their association with multiple diseases and healthy people in this review to deepen the ophthalmologists' understanding of PHOMS. Additionally, we provide some new directions for future research.

Prevalence of optic disc drusen: A systematic review, meta-analysis and forecasting study

Optic disc drusen (ODD) are calcium-containing deposits in the optic nerve head, capable of causing visual field defects and sudden visual loss. The underlying pathophysiology remains inadequately understood and treatment options are missing. In this paper, we systematically reviewed prevalence studies of ODD in non-selected populations to provide an overview of its prevalence, conducted meta-analyses to determine modality-specific prevalence estimates and performed a forecasting study to estimate current and future global population number of individuals with ODD. We searched 11 literature databases on 25 October 2022 for prevalence studies of ODD in non-selected populations. Eight eligible studies provided data from a total of 27 463 individuals. Prevalence estimates were stratified according to diagnostic modalities: ophthalmoscopy 0.37% (95% CI: 0.10-0.95%), fundus photography 0.12% (95% CI: 0.03-0.24%), spectral domain optical coherence tomography with enhanced depth imaging 2.21% (95% CI: 1.25-3.42%) and histopathology 1.82% (95% CI: 1.32-2.38%). Using histopathology-based summary prevalence estimate, we forecast 145 million individuals with ODD currently, a number expected to increase further due to world population growth. These numbers underscore the importance of including ODD in health education and highlight the necessity of continuing research in ODD.

NAION or not NAION? A literature review of pathogenesis and differential diagnosis of anterior ischaemic optic neuropathies

PURPOSE

To offer a comprehensive review of the available data regarding non-arteritic anterior ischaemic optic neuropathy and its phenocopies, focusing on the current evidence to support the different existing aetiopathogenic hypotheses for the development of these conditions.

CONCLUSIONS AND IMPORTANCE

Due to the limited array of responses of the neural tissue and other retinal structures, different aetiopathogenic mechanisms may result in a similar clinical picture. Moreover, when the insult occurs within a confined space, such as the optic nerve or the optic nerve head, in which different tissues (neural, glial, vascular) are highly interconnected and packed together, determining the primary noxa can be challenging and may lead to misdiagnosis. Anterior ischaemic optic neuropathy is a condition most clinicians will face during their everyday work, and it is important to correctly differentiate among resembling pathologies affecting the optic nerve to avoid unnecessary diagnostic procedures. Combining a good clinical history and multimodal imaging can assist diagnosis in most cases. The key remains to combine demographic data (e.g. age), with ophthalmic data (e.g. refractive error), systemic data (e.g. comorbidities and medication), imaging data (e.g. retinal OCT) with topographic signs (e.g. focal neurology).

METHODOLOGY

Papers relevant for this work were obtained from the MEDLINE and Embase databases by using the PubMed search engine. One author (MPMG) performed the search and selected only publications with relevant information about the aetiology, pathogenic mechanisms, risk factors as well as clinical characteristics of phenocopies (such as vitreopapillary traction, intrapapillary haemorrhage with adjacent peripapillary subretinal haemorrhage or diabetic papillopathy) of non-arteritic anterior ischaemic optic neuropathy (NAION). The terms "non-arteritic ischaemic optic neuropathy/NAION", "vitreopapillary traction", "vitreopapillary traction AND non-arteritic ischaemic optic neuropathy/NAION", "posterior vitreous detachment AND non-arteritic ischaemic optic neuropathy/NAION", "central retinal vein occlusion AND non-arteritic ischaemic optic neuropathy/NAION", "disc oedema/disc oedema", "diabetes mellitus AND non-arteritic ischaemic optic neuropathy/NAION" and "diabetic papillopathy" were searched on PubMed. From each of these searches, publications were selected based on their title, obtaining a total of 115 papers. All papers not written in English were then excluded, and those whose abstracts were not deemed relevant for our review, according to the aforementioned criteria. Subsequent scrutiny of the main text of the remaining publications led us (MPMG, AP, ZS) to include references which had not been selected during our first search, as their titles did not contain the previously mentioned MeSH terms, due to their significantly relevant contents for our work. A total of 62 publications were finally consulted for our review. The literature review was last updated on 24-Aug-2022.

Features of Peripapillary Hyperreflective Ovoid Mass-Like Structures in Nonarteritic Anterior Ischemic Optic Neuropathy Patients and Normal Controls

Purpose

To determine the characteristics of peripapillary hyperreflective ovoid mass-like structures (PHOMS) in patients with nonarteritic anterior ischemic optic neuropathy (NAION) and in normal adults.

Methods

A total of 406 included eyes were divided into four groups: acute NAION group, chronic NAION group, unaffected group, and normal eyes group. PHOMS were detected on optical coherence tomography slices from optical coherence tomography angiography scans centered on the optic nerve head (ONH). The differences in age, sex, and ONH parameters were investigated between eyes with PHOMS and eyes without PHOMS among groups.

Results

The prevalence of PHOMS in acute eyes (43.48%) and fellow eyes (28.20%) was significantly higher than that in normal eyes (11.76%) (acute vs. normal, P < 0.001; fellow vs. normal, P = 0.014). In the acute group, the PHOMS score of size was negatively correlated with age in acute eyes (r = -0.486, P = 0.03). The size of PHOMS was negatively correlated with age and cup/disc ratio and positively correlated with retinal nerve fiber layer thickness in the nasal and inferior sectors in the normal groups. No differences in age, sex, ONH parameters, or visual field defects were found between eyes with PHOMS and eyes without PHOMS.

Conclusions

The prevalence of PHOMS increased significantly in acute nonoptic disc drusen (NODD)-NAION eyes and fellow eyes. PHOMS could also be found among normal adults. PHOMS may be a nonspecific sign secondary to ONH edema and axoplasmic stasis.

Translational Relevance

The high prevalence of PHOMS in acute NODD-NAION eyes may indicate axoplasmic stasis secondary to tissue edema.

Artificial Intelligence-Based ChatGPT Responses for Patient Questions on Optic Disc Drusen

INTRODUCTION

Optic disc drusen (ODD) are acellular deposits in the optic nerve head, which are most often benign and asymptomatic. Patients may develop visual field defects and be at increased risk of ischemic co-morbidities. As ODD can be difficult to distinguish from papilledema, patients are at risk of unnecessary clinical workups. Patient information is a key aspect of ODD management. In this study, we explored the accuracy of ChatGPT responses for typical patient questions on ODD.

METHODS

Two content experts reached consensus on 20 typical patient questions. We retrieved five separate responses for each question from ChatGPT, totaling 100 responses. Each response was evaluated on a 5-point Likert-scale on accuracy by each content expert in an individual fashion.

RESULTS

The two experts were in fair/substantial agreement in the evaluation of responses (Cronbach's alpha: 0.64). Of the 100 responses, 17 were relevant and without any inaccuracies, 78 were relevant and with inaccuracies not being harmful, and five were relevant and with inaccuracies potentially harmful. The lowest accuracy scores were obtained for questions dealing with treatment and prognosis.

CONCLUSIONS

ChatGPT often provides relevant answers for patient questions on ODD, but inaccuracies become potentially harmful when questions deal with treatment and prognosis.

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.

[Nonarteritic anterior ischemic optic neuropathy (nAION)]

Nonarteritic anterior ischemic optic neuropathy (nAION) is the second most common degenerative disease of the optic nerve. The pathogenesis remains elusive. A transient ischemia in the short posterior ciliary arteries not triggered by thromboembolic events is suspected. The typical history of a sudden onset of scotoma without associated pain in conjunction with (sectorial) optic disc swelling, an afferent pupillary defect and a visual field defect are of decisive diagnostic importance. The most urgent diagnostic measure is the exclusion of arteritic AION. There are no proven treatment approaches. Frequently used but without clear study results, is the treatment with steroids and secondary prophylaxis with acetylsalicylic acid (ASA). Recurrence in the ipsilateral or contralateral eye is possible.

Peripapillary Vessel Density in Relation to Optic Disc Drusen: A Multimodal Optical Coherence Tomography Study

BACKGROUND

Optic disc drusen (ODD) are acellular calcified deposits within the optic nerve head known to cause visual field defects. An emerging gold standard for the diagnosis of ODD is enhanced depth imaging optical coherence tomography (EDI-OCT). The presence of ODD affects the adjacent peripapillary vasculature, which can be visualized using OCT angiography (OCTA). This study investigates the association between peripapillary vessel density and anatomical ODD location and volume using a newly developed method of multimodal OCT.

METHODS

A case-control study with 16 patients diagnosed with ODD in the period 2008-2017 and 24 healthy controls. All patients and controls had EDI-OCT, OCTA, and demographic data collected. Using EDI-OCT and the medical imaging segmentation tool ITK-SNAP, 3-dimensional (3D) visualization of ODD in patients were created. ODD 3D visualization and corresponding OCTA scans were superimposed, making it possible to correlate ODD volume to the peripapillary vessel density in the corresponding modified Garway-Heath segments of the optic disc.

RESULTS

We found that mean peripapillary vessel density across all modified Garway-Heath segments were lower in ODD patients compared with controls with significant reduction of peripapillary vessel density in the superior segment ( P = 0.03) and globally ( P = 0.05). A significant inverse proportionality between ODD volume and peripapillary vessel density in the corresponding segment was seen ( P = 0.002).

CONCLUSIONS

We found a reduced peripapillary vessel density in regions with close anatomical proximity to ODD and inverse proportionality between ODD volume and peripapillary vessel density.

Peripapillary hyper-reflective ovoid mass-like structures (PHOMS): clinical significance, associations, and prognostic implications in ophthalmic conditions

Pioneering advancements in optical coherence tomography (OCT) have facilitated the discernment of peripapillary hyper-reflective ovoid mass-like structures (PHOMS), prevalent neuro-ophthalmological findings associated with an array of ophthalmic conditions, such as optic disc drusen (ODD), papilledema, myopic/tilted optic discs, non-arteritic anterior ischemic optic neuropathy (NA-AION), and optic neuritis. Despite an expanding corpus of research, numerous inquiries persist concerning their clinical significance, correlations with ocular afflictions, and prognostic implications. This comprehensive review endeavors to impart an in-depth comprehension of PHOMS, encompassing facets like conceptualization, detection, pathogenesis, and associations with diverse ophthalmic conditions. Furthermore, we underscore several unresolved quandaries and suggest prospective avenues for future exploration.

Peripapillary hyper-reflective ovoid mass-like structures (PHOMS) in AQP4-IgG-positive neuromyelitis optica spectrum disease (NMOSD) and MOG-IgG-associated disease (MOGAD)

BACKGROUND

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) have recently been described as new optical coherence tomography (OCT) marker. It is not yet clear whether the occurrence of PHOMS is disease-specific or disease-spanning. PHOMS have been described in 16-18% of patients with multiple sclerosis (MS). Currently, no data on the prevalence of PHOMS in other demyelinating diseases including aquaporine-4-IgG-positive neuromyelitis optica spectrum disease (AQP4 + NMOSD) or myelin oligodendrocyte glycoprotein-IgG-associated disease (MOGAD) are reported.

METHODS

We performed a cross-sectional, retrospective spectral domain OCT study evaluating the frequency of PHOMS in AQP4 + NMOSD (n = 47) and MOGAD (n = 44) patients. To test the association with retinal neuroaxonal damage, we compared demographic and clinical data as well as retinal layer thicknesses between eyes with vs. eyes without PHOMS.

RESULTS

PHOMS were detected in 17% of AQP4 + NMOSD and 14% of MOGAD patients. Intra-cohort analysis revealed that AQP4 + NMOSD patients with PHOMS were significantly older [mean (years): 57.5 vs. 50.0; p value = 0.04]. We found no association of PHOMS with retinal neuroaxonal degeneration. In addition, in subjects with only one eye affected by PHOMS compared with the unaffected fellow eye, no differences in retinal parameters were observed (n = 4).

CONCLUSIONS

In summary, we found PHOMS in 17% of AQP4 + NMOSD and 14% of MOGAD patients. This is comparable to the prevalence of published MS PHOMS data. Therefore, a disease-specific occurrence of PHOMS is unlikely. Interestingly, PHOMS do not seem to depend on retinal neuroaxonal degeneration.

Peripapillary hyperreflective ovoid mass-like structures: Multimodal imaging-A review

Peripapillary hyperreflective ovoid mass-like structures (PHOMS) are a laterally bulging herniation of distended axons into the peripapillary region above the level of Bruch's membrane opening. Increased use of enhanced depth imaging-optical coherence tomography (EDI-OCT) in our evaluation of the optic nerve head (ONH) and greater recognition of the vast range of optic nerve pathologies with which PHOMS is associated provides convincing evidence that PHOMS is not just buried optic disc drusen (ODD) as previously described. The frequent coexistence of PHOMS with ODD, papilloedema, anterior ischaemic optic neuropathy, tilted optic disc syndrome, inflammatory demyelinating disorders and other diseases associated with axoplasmic stasis provides insight into its underlying pathophysiology. The present review will discuss the role of key imaging modalities in the differential diagnosis of PHOMS, explore the current literature on the relationship between PHOMS and common neuro-ophthalmic conditions, and highlight the gaps in our knowledge, with respect to disease classification and prognosis, to pave the way for future directions of research.

An overview of peripapillary hyperreflective ovoid mass-like structures

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the ophthalmic findings associated with peripapillary hyperreflective ovoid mass-like structures (PHOMS) in both adult and pediatric patients.

RECENT FINDINGS

PHOMS have recently been identified in a number of different ophthalmic disease entities ranging from nonpathologic to pathologic, including but not limited to anatomic abnormalities (tilting in myopia), optic nerve head drusen, optic disc edema from inflammation (optic neuritis, white dot syndromes), vascular insults (ischemic optic neuropathy, retinal vascular occlusion), and papilledema. The mechanism underlying the formation of PHOMS has not been fully elucidated although it has been hypothesized that PHOMS occur secondary to axoplasmic stasis from crowding at the optic nerve head.

SUMMARY

Although the clinical significance of the presence of PHOMS remains unclear, PHOMS are associated with several disease processes. Understanding the mechanism behind their formation and their impact on optic nerve head structure and visual function may be relevant in patients with optic nerve head pathology. The presence of PHOMS may also correlate with disease severity and duration. Future studies to evaluate whether the formation of PHOMS may be useful as an early indicator of disease or a prognostic tool are warranted.

Comparison of Spectral-Domain OCT versus Swept-Source OCT for the Detection of Deep Optic Disc Drusen

Deep optic disc drusen (ODD) are located below Bruch’s membrane opening (BMO) and may go undetected due to the challenges in imaging them. The purpose of this study is a head-to-head comparison of currently widely used imaging technologies: swept-source optical coherence tomography (SS-OCT; DRI OCT-1 Triton, Topcon) and enhanced depth imaging spectral-domain optical coherence tomography (EDI SD-OCT; Spectralis OCT, Heidelberg Engineering) for the detection of deep ODD and associated imaging features. The eyes included in this study had undergone high-resolution imaging via both EDI SD-OCT and SS-OCT volume scans, which showed at least one deep ODD or a hyperreflective line (HL). Grading was performed by three graders in a masked fashion. The study findings are based on 46 B-scan stacks of 23 eyes including a total of 7981 scans. For scan images with ODD located above or below the level of BMO, no significant difference was found between the two modalities compared in this study. However, for HLs and other features, EDI SD-OCT scan images had better visualization and less artifacts. Although SS-OCT offers deep tissue visualization, it did not appear to offer any advantage in ODD detection over a dense volume scan via EDI SD-OCT with B-scan averaging.

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.

Diabetic papillopathy in patients with optic disc drusen: Description of two different phenotypes

PURPOSE

To describe two cases of severe acute bilateral optic disc edema that occurred in patients with diabetes mellitus shortly after the initiation of intensified antihyperglycemic therapy.

METHODS

Retrospective observational case report.

CASE DESCRIPTION

Two patients with type 1 diabetes presented for routine retinopathy screening with asymptomatic optic disc edema. One case was bilateral, the other unilateral. Neither patient had visual complaints. Both patients' glycemia history was characterized by a recent bout of poor regulation and both had optic disc edema consistent with diabetic papillopathy in combination with prominent Optic disc drusen (ODD). The swelling that appeared to constitute the edematous diabetes-related component of the disease resolved within 10-12 weeks during which diabetes therapy was optimized. Visual field deficits were seen early on in both patients and had resolved to some extent in one patient after 9 months but persisted in the one affected eye in the other patient up to at least 30 months.

CONCLUSION

Two cases of ODD-associated diabetic papillopathy were observed: One with classic, bilateral disc edema and minor visual field defects, the other with unilateral disc edema, severe visual field defects and a phenotype that resembled non-arteritic anterior ischemic optic neuropathy. The cases suggest that ODD may increase the risk of diabetic papillopathy, a condition that is associated with rapid glycemia reduction and crowded optic discs, which may combine to produce nerve fiber swelling and hypoperfusion with venous congestion in a compartment with limited room for expansion.

Non-arteritic anterior ischaemic optic neuropathy (NA-AION) and COVID-19 vaccination

A woman in her 50s presented with diminution of vision in her left eye (OS) 4 days after COVISHIELD^TM vaccination. She had been diagnosed with non-arteritic anterior ischaemic optic neuropathy (NA-AION) of right eye (OD) 8 months earlier. The present episode revealed a best-corrected visual acuity (BCVA) of 20/50 in OD and 20/20 in OS with grade 1 relative afferent pupillary defect. Fundus evaluation showed pale disc in OD and temporal disc oedema in OS. Humphrey’s visual field analysis showed incomplete inferior altitudinal defect in OD and a centro-caecal scotoma in OS. Systemic investigations were normal. OS was diagnosed with NA-AION. She was started on oral aspirin 75 mg. At 1-month follow-up, disc oedema of OS had resolved with BCVA maintaining at 20/20. The patient was lost to follow-up later. The relationship between the vaccine and the ocular event is temporal with no causal association.

Volumetric Measurement of Peripapillary Hyperreflective Ovoid Masslike Structures in Patients with Optic Disc Drusen

Purpose

To develop a method to determine the volume of peripapillary hyperreflective ovoid masslike structures (PHOMS) and to examine the correlation between PHOMS and anatomic optic nerve head characteristics in a large cohort of patients with optic disc drusen (ODD).

Design

Retrospective, observational study of patients with ODD.

Participants

Patients with ODD seen in a 3-year period.

Methods

We determined the prevalence of PHOMS. We then developed a method to calculate the volume of PHOMS and measured this in all patients where radial scans on OCT were available. We analyzed the correlation between PHOMS volume and patient age, size of Bruch's membrane opening (BMO), ODD visibility, and anatomic location of ODD in the optic nerve.

Main Outcome Measures

Prevalence and characteristics of PHOMS in patients with ODD.

Results

In 247 (77%) eyes with ODD, PHOMS were found. Among these, 80% were in the first decade of life, 87% were in the second decade, 89% were in the third decade, 85% were in the fourth decade, 74% were in the fifth decade, 73% were in the sixth decade, 58% were in the seventh decade, 40% were in the eighth decade, and 0% were in the ninth decade. The ophthalmoscopic visibility of ODD increased with age. The volume of PHOMS decreased with age, but with no correlation to the size of BMO. The median volume of PHOMS was 0.27 mm3 (interquartile range [IQR], 0.13-0.49 mm3). Predominantly, PHOMS were observed in the nasal peripapillary area (87.5% nasal, 78.5% superior, 67% inferior, and 63.5% temporal).

Conclusions

In patients with ODD, PHOMS are seen frequently, with the highest prevalence in younger individuals. The volume of PHOMS decreases with age, and PHOMS are seen more frequently in patients with superficial ODD.

Clinical and Multi-Mode Imaging Features of Eyes With Peripapillary Hyperreflective Ovoid Mass-Like Structures

Purpose

To observe and analyze the clinical and multi-mode imaging features of eyes with PHOMS, and to introduce two cases of PHOMS which underwent multi-mode imaging.

Methods

Retrospective clinical observational study. A total of 26 patients (37 eyes) with hyperreflective structures surrounded by hyporeflective edges around the optic discs who were examined and diagnosed at Shandong Eye Hospital between January 2019 and June 2021 were included in the study. Among these patients, 12 were male and 14 were female. Fifteen were monocular. The average age was 39 years. All patients underwent the following examinations: Best-corrected visual acuity (BCVA), intraocular pressure examinations, slit-lamp anterior segment examinations, indirect ophthalmoscopy, visual field examinations, fundus color photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), and optical coherence tomography angiography (OCTA). Some of the patients were examined with fundus fluorescein angiography (FFA). Clinical data and imaging characteristics from the OCT, OCTA, and FFA were analyzed retrospectively.

Results

We found the hyperreflective structures surrounded by hyporeflective edges around the optic discs in 37 eyes. EDI-OCT results revealed hyperreflective structures surrounded by hyporeflective edges around the optic discs in all eyes. Typical hyperreflexia lesions occurred around the optic disc, located subretinally and above Bruch's membrane. OCTA revealed that the highly reflective perioptic material also had vascular structures.

Conclusion

EDI-OCT of PHOMS showed hyperreflective structures surrounded by hyporeflective edges around all of the optic discs. Infra-red photography showed temporal hyperreflexia. These characteristics can be seen in a variety of diseases and may be a relatively common feature revealed by EDI-OCT scanning. These characteristics may also be seen in elderly patients as well as children. PHOMS may be found in optic disc drusen (ODD), tilted disc syndrome (TDS), optic neuritis, ischemic optic neuropathy, and in white dot syndromes. Few patients may be developed into macular neovascularization (MNV). In order to improve the accuracy and robustness of the conclusions and provide better clinical guidance, we need to conduct more comprehensive research in the subsequent clinical work.

Peripapillary Hyper-reflective Ovoid Mass-like Structure (PHOMS): An Optical Coherence Tomography Marker of Axoplasmic Stasis in the Optic Nerve Head

BACKGROUND

With the development and widespread adoption of spectral-domain optical coherence tomography (OCT), peripapillary hyper-reflective ovoid mass-like structures (PHOMS) have become a frequent OCT finding in neuro-ophthalmic practice. Although originally assumed to represent a form of buried optic disc drusen (ODD), PHOMS differ from ODD in many important ways. The histopathological underpinnings of PHOMS are now becoming more clearly understood.

EVIDENCE ACQUISITION

Review of literature.

RESULTS

PHOMS can be broadly classified as disk edema-associated PHOMS, ODD-associated PHOMS, or anomalous disk-associated PHOMS. PHOMS are seen in many conditions, including papilledema, nonarteritic anterior ischemic optic neuropathy, central retinal vein occlusion, acute demyelinating optic neuritis, ODD, and tilted disks (myopic obliquely inserted disks) and in many cases resolve along with the underlying condition. The histopathological study of these diverse entities reveals the common feature of a bulge of optic nerve fibers herniating centrifugally over Bruch membrane opening into the peripapillary space, correlating exactly with the location, shape, and space-occupying nature of PHOMS on OCT. Because of the radial symmetry of these herniating optic nerve fibers, PHOMS are best thought of as a complete or partial torus (i.e., donut) in 3 dimensions.

CONCLUSIONS

PHOMS are a common but nonspecific OCT marker of axoplasmic stasis in the optic nerve head. They are not themselves ODD or ODD precursors, although they can be seen in association with ODD and a wide spectrum of other conditions. They do not exclude papilledema and often accompany it. The circumferential extent and characteristic 3D toroidal nature of a PHOMS are best appreciated by scrolling through consecutive OCT images.

Oxidative Stress in Optic Neuropathies

Increasing evidence indicates that changes in the redox system may contribute to the pathogenesis of multiple optic neuropathies. Optic neuropathies are characterized by the neurodegeneration of the inner-most retinal neurons, the retinal ganglion cells (RGCs), and their axons, which form the optic nerve. Often, optic neuropathies are asymptomatic until advanced stages, when visual impairment or blindness is unavoidable despite existing treatments. In this review, we describe systemic and, whenever possible, ocular redox dysregulations observed in patients with glaucoma, ischemic optic neuropathy, optic neuritis, hereditary optic neuropathies (i.e., Leber's hereditary optic neuropathy and autosomal dominant optic atrophy), nutritional and toxic optic neuropathies, and optic disc drusen. We discuss aspects related to anti/oxidative stress biomarkers that need further investigation and features related to study design that should be optimized to generate more valuable and comparable results. Understanding the role of oxidative stress in optic neuropathies can serve to develop therapeutic strategies directed at the redox system to arrest the neurodegenerative processes in the retina and RGCs and ultimately prevent vision loss.

Updates on ophthalmic imaging features of optic disc drusen, papilledema, and optic disc edema

Purpose of review

Optic nerve head elevation can be associated with vision loss. This review provides an update regarding key features of optic disc drusen (ODD) compared with papilledema from increased intracranial pressure and optic disc edema from other causes.

Recent findings

Clinical history and funduscopic examination are not sufficient to correctly diagnose different causes of optic nerve head elevation. Multimodal ophthalmic imaging is noninvasive and should be used as first-line diagnostic testing to distinguish optic disc edema or papilledema from pseudoedema. Advanced ophthalmic imaging, including enhanced depth imaging optical coherence tomography (EDI-OCT) and autofluorescence imaging, can visualize ODD at high resolution and determine whether there is optic disc edema. OCT angiography does not require contrast and can rapidly visualize papillary, peripapillary, and macular microvasculature and identify important vascular biomarker of ischemia and, potentially, visual prognosis.

Summary

Multimodal ophthalmic imaging can help in the diagnosis of ODD and optic disc edema and identify patients at high risk of vision loss and neurological issues in order to ensure appropriate diagnosis and treatment.

Re-evaluating diabetic papillopathy using optical coherence tomography and inner retinal sublayer analysis

Background/Objectives

To re-evaluate diabetic papillopathy using optical coherence tomography (OCT) for quantitative analysis of the peripapillary retinal nerve fibre layer (pRNFL), macular ganglion cell layer (mGCL) and inner nuclear layer (mINL) thickness.

Subjects/Methods

In this retrospective observational case series between June 2008 and July 2019 at Moorfields Eye hospital, 24 eyes of 22 patients with diabetes and optic disc swelling with confirmed diagnosis of NAION or diabetic papillopathy by neuro-ophthalmological assessment were included for evaluation of the pRNFL, mGCL and mINL thicknesses after resolution of optic disc swelling.

Results

The mean age of included patients was 56.5 (standard deviation (SD) ± 14.85) years with a mean follow-up duration of 216 days. Thinning of pRNFL (mean: 66.26, SD ± 31.80 µm) and mGCL (mean volume: 0.27 mm³, SD ± 0.09) were observed in either group during follow-up, the mINL volume showed no thinning with 0.39 ± 0.05 mm³. The mean decrease in visual acuity was 4.13 (SD ± 14.27) ETDRS letters with a strong correlation between mGCL thickness and visual acuity (rho 0.74, p < 0.001).

Conclusion

After resolution of acute optic disc swelling, atrophy of pRNFL and mGCL became apparent in all cases of diabetic papillopathy and diabetic NAION, with preservation of mINL volumes. Analysis of OCT did not provide a clear diagnostic distinction between both entities. We suggest a diagnostic overlay with the degree of pRNFL and mGCL atrophy of prognostic relevance for poor visual acuity independent of the semantics of terminology.

Topographic Quadrant Analysis of Peripapillary Superficial Microvasculature in Optic Disc Drusen

Background: Limited information is known about the topographic effect of optic disc drusen (ODD) on peripapillary retinal nerve fibers and microvasculature. Objective: This study aims to understand the structural and functional impact of ODD in different quadrants of the optic disc. Methods: We performed a retrospective case-control study of 22 ODD patients (34 eyes) and 26 controls (33 eyes) to compare optical coherence tomography (OCT) retinal nerve fiber layer (RNFL), OCT angiography (OCTA), and corresponding static perimetry mean deviation (MD) calculated using the modified Garway-Heath map in different quadrants of the optic disc. OCTA was analyzed using custom MATLAB script to measure six parameters in a peripapillary annulus with large vessel removal: vessel area density (VAD), vessel skeleton density (VSD), vessel perimeter index (VPI), vessel complexity index (VCI), flux, and vessel diameter index (VDI). Results: Quadrant analysis revealed that OCTA VAD and VCI were significantly decreased in superior, nasal, and inferior but not temporal quadrant. RNFL, VSD, and VPI were significantly impacted only in the superior and nasal quadrants. Corresponding visual field MDs in all ODD eyes were not different in the four quadrants, although eyes with MD equal or worse than -5 dB (32%) had worst visual field corresponding to the superior quadrant of the optic disc (inferior arcuate visual field). Structure-structure comparison of OCT and OCTA showed high correlation of RNFL with multiple OCTA measurements in the superior, nasal, and inferior quadrants but not temporal quadrant. Structure-function analysis revealed significant correlation of VAD and VCI and visual field MD in every quadrant, but RNFL was only significantly correlated in the superior and inferior quadrants. Conclusions: Peripapillary VAD and VCI are decreased in more quadrants than RNFL, supporting the clinical utility of performing OCTA in addition to OCT. Consistent with the most common locations of ODD, five OCT/OCTA measurements (VAD, VCI, RNFL, VSD, VPI) are decreased in the superior and nasal quadrants. OCT/OCTA measurements were significantly impacted in contrast to the relatively mild effect on corresponding visual field MD, consistent with the idea that a decrease in objective structural and vascular measurements occurs without parallel change in subjective visual function in ODD.

Risk factors and visual outcome of Non-Arteritic Ischemic Optic Neuropathy (NAION): Experience of a tertiary center in Kuwait

Background

Non-arteritic ischemic optic neuropathy (NAION) is the most common acute optic neuropathy over the age of 50 years. NAION is commonly associated with systemic vascular risk factors (diabetes, hypertension, hyperlipidemia) and small cup-to-disc-ratio. We have assessed the prevalence risk factors of NAION and the visual outcome in patients referred to a tertiary ophthalmology center in Kuwait.

Materials and methods

A retrospective review of new cases of NAION presenting within 2 weeks of onset were included and baseline clinical and demographics characteristic were determined. The prevalence of risk factors and the visual outcome (change in logMAR visual acuity, mean deviation of visual field) was compared between young NAION patients (below 50 years of age) and older NAION patients (over 50 years of age). The odds ratio of a final favorable visual outcome (visual acuity 20/40 or better) by age category was determined.

Results

Seventy-eight eyes of 78 patients with recent onset NAION were included in the study. The most prevalent risk factors for NAION in our subjects were diabetes (64.1%), small cup-to-disc ratio (61.5%), hyperlipidemia (51.3%) and hypertension (38.5%). Young NAION patients had better final logMAR visual acuity (0.55 +- 0.57) then older NAION patients (0.9 +- 0.73), (p = 0.03). Furthermore, young NAION patients were 2.8 times more likely to have a final visual acuity of 20/40 or better than older NAION patients, odds ratio (OR), 2.87; 95% confidence interval (CI), 1.12–7.40, Chi-square p-value = 0.03).

Conclusion

There is a high prevalence of systemic vascular risk factors and small cup-to-disc ratio in NAION patients referred to our center across different age groups (below and above 50 years). Patients below the age of 50 years with NAION are more likely to have a final visual acuity of 20/40 or better than NAION patients above the age of 50 years.

Recent advances and future directions on the use of optical coherence tomography in neuro-ophthalmology

Optical coherence tomography (OCT) is a noninvasive imaging technique used to qualitatively and quantitatively analyze various layers of the retina. OCT of the retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) is particularly useful in neuro-ophthalmology for the evaluation of patients with optic neuropathies and retrochiasmal visual pathway disorders. OCT allows for an objective quantification of edema and atrophy of the RNFL and GCIPL, which may be evident before obvious clinical signs and visual dysfunction develop. Enhanced depth imaging OCT allows for visualization of deep structures of the optic nerve and has emerged as the gold standard for the detection of optic disc drusen. In the evaluation of compressive optic neuropathies, OCT RNFL and GCIPL thicknesses have been established as the most important visual prognostic factor. There is increasing evidence that inclusion of OCT as part of the diagnostic criteria for multiple sclerosis (MS) increases its sensitivity. Moreover, OCT of the RNFL and GCIPL may be helpful in the early detection and monitoring the treatment of conditions such as MS and Alzheimer's disease. OCT is an important aspect of the neuro-ophthalmologic assessment and its use is likely to increase moving forward.

Diagnosing Optic Disc Drusen in the Modern Imaging Era: A Practical Approach

Optic disc drusen (ODD) are a well-recognised cause of an elevated optic disc appearance. When visible with ophthalmoscopy and fundus photography, ODD are readily identified. Yet, in more subtle cases of ODD, ancillary testing may be needed to render the diagnosis. Facilitating the diagnosis of ODD has clinical relevance, because affected individuals may otherwise undergo unnecessary costly and invasive investigations to rule out raised intracranial pressure and other causes of optic disc oedema. In this review, the role of established and emerging optical coherence tomography (OCT) techniques in the diagnosis and management of ODD cases is reviewed. A practical approach is taken to explain how to optimise use of commercially available OCT technology in the clinical setting. Optical coherence tomography provides many advantages over other imaging modalities in the diagnosis of ODD, including the ability to correlate retinal measures of neuroaxonal structure with drusen characteristics. Earlier spectral domain OCT techniques, however, were hindered by poor penetrance. In the modern imaging era, enhanced depth imaging OCT and swept source OCT enable higher resolution of ODD and other optic nerve head structures that might otherwise be mistaken for drusen. Ongoing studies featuring OCT angiography indicate that this technique may provide complementary information about microvascular supply that correlate with structural measures of optic nerve injury. Advances in OCT will continue to improve diagnostic accuracy and inform clinical understanding regarding structure-function correlations germane to the longitudinal follow up of ODD patients.

Anterior Ischaemic Optic Neuropathy following Liposuction in a Patient with Optic Disc Drusen

Ischaemic optic neuropathy (ION) following non-ocular surgeries is a rare but devastating complication. Spine and cardiovascular surgical procedures are well known to be accompanied by this complication. ION after liposuction surgery is gaining attention during the past decades due to the escalating demand for this procedure. We report a case of unilateral anterior ION (AION) after abdominoplasty and liposuction in an eye with optic disc drusen (ODD), which has not been reported previously. The presence of ODD is not only an independent risk factor for AION in young patients, but could also be the underlying cause of the ischaemic insult to the optic nerve head in haemodynamically unstable patients.

Optic Nerve Head Blood Flow Analysis in Patients with Optic Disc Drusen Using Laser Speckle Flowgraphy

Visual field defects are common in patients with optic disc drusen (ODD). Our aim was to examine whether reduced optic nerve head (ONH) microcirculation is related to visual field defects in ODD patients. Vascular and tissue area mean blur rate (MBR_V and MBR_T), measured using laser speckle flowgraphy (LSFG), was significantly lower in the 32 included ODD eyes when compared with 40 healthy eyes (p <.05). There was a moderate correlation between the difference in MBR_T and the perimetric mean defect (R² = 0.53) in ODD patients. These findings demonstrate the utility of LSFG in examining ONH blood flow in ODD patients.