Treatment of Nonarteritic Acute Central Retinal Artery Occlusion

Plasmalogens and Octanoylcarnitine Serve as Early Warnings for Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is a kind of ophthalmic emergency which may cause loss of functional visual acuity. However, the limited treatment options emphasize the significance of early disease prevention. Metabolomics has the potential to be a powerful tool for early identification of individuals at risk of CRAO. The aim of the study was to identify potential biomarkers for CRAO through a comprehensive analysis. We employed metabolomics analysis to compare venous blood samples from CRAO patients with cataract patients for the venous difference, as well as arterial and venous blood from CRAO patients for the arteriovenous difference. The analysis of metabolites showed that PC(P-18:0/22:6(4Z,7Z,10Z,13Z,16Z,19Z)), PC(P-18:0/20:4(5Z,8Z,11Z,14Z)) and octanoylcarnitine were strongly correlated with CRAO. We also used univariate logistic regression, random forest (RF), and support vector machine (SVM) to screen clinical parameters of patients and found that HDL-C and ApoA1 showed significant predictive efficacy in CRAO patients. We compared the predictive performance of the clinical parameter model with combined model. The prediction efficiency of the combined model was significantly better with area under the receiver operating characteristic curve (AUROC) of 0.815. Decision curve analysis (DCA) also exhibited a notably higher net benefit rate. These results underscored the potency of these three substances as robust predictors of CRAO occurrence.

Plasma Proteomics to Identify Drug Targets and Potential Drugs for Retinal Artery Occlusion: An Integrated Analysis in the UK Biobank

Retinal artery occlusion (RAO), which is positively correlated with acute ischemic stroke (IS) and results in severe visual impairment, lacks effective intervention drugs. This study aims to perform integrated analysis using UK Biobank plasma proteome data of RAO and IS to identify potential targets and preventive drugs. A total of 7191 participants (22 RAO patients, 1457 IS patients, 8 individuals with both RAO and IS, and 5704 healthy age-gender-matched controls) were included in this study. Unique 1461 protein expression profiles of RAO, IS, and the combined data set, extracted from UK Biobank Plasma proteomics projects, were analyzed using both differential expression analysis and elastic network regression (Enet) methods to identify shared key proteins. Subsequent analyses, including single cell type expression assessment, pathway enrichment, and druggability analysis, were conducted for verifying shared key proteins and discovery of new drugs. Five proteins were found to be shared among the samples, with all of them showing upregulation. Notably, adhesion G-protein coupled receptor G1 (ADGRG1) exhibited high expression in glial cells of the brain and eye tissues. Gene set enrichment analysis revealed pathways associated with lipid metabolism and vascular regulation and inflammation. Druggability analysis unveiled 15 drug candidates targeting ADGRG1, which demonstrated protective effects against RAO, especially troglitazone (-8.5 kcal/mol). Our study identified novel risk proteins and therapeutic drugs associated with the rare disease RAO, providing valuable insights into potential intervention strategies.

Retinal Artery Reperfusion After Translumenal YAG Laser Embolysis in a Case of Branch Retinal Artery Occlusion

Purpose: To present a potential treatment for embolic branch retinal artery occlusion (BRAO). Methods: A case and its findings were analyzed. Results: A 75-year-old man with a 5-day history of an acute superior visual field defect in the right eye was found to have a BRAO secondary to a Hollenhorst plaque and was treated with translumenal YAG laser embolysis. Reperfusion of the retinal artery was observed on dislodging the Hollenhorst plaque, and improvements were seen in the patient's superior visual field defect. Conclusions: Translumenal YAG laser embolysis could potentially reverse ischemia secondary to embolic RAOs. This case report and the current literature cited suggest a rationale for treatment and supports further study of this technique.

Thrombolytic Therapy for Central Retinal Artery Occlusion in an Academic Multi-Site Stroke Centre

Central retinal artery occlusion (CRAO) is a subtype of acute ischaemic stroke leading to severe visual loss. A recent American Heart Association scientific statement proposed time-windows for thrombolysis in CRAO similar to acute ischaemic cerebral strokes. We aimed to review our academic multi-site stroke centre experience with intravenous (IVT) and intra-arterial thrombolysis (IAT) in CRAO between 1997 and 2022. Demographic, clinical characteristics, thrombolysis timeline, concurrent therapies, complications, and 3-month follow-up visual acuity (VA) were collected. The thrombolysed cohort follow-up VA was compared with an age, gender and baseline VA matched cohort of CRAO patients that received conservative therapies. Thrombolytic therapy was administered to 3.55% (n = 20) of CRAO admissions; 13 IVT (mean age 68, 61.5% male, 12 alteplase and 1 tenecteplase, all embolic aetiology, 1 CRAO mimic) and 7 IAT (mean age 55, 85.7% male, 3 post-operative and 3 embolic). Additional conservative CRAO-targeting therapies was received by 60%. The median time from onset of visual loss to IVT was 158 minutes (range 67-260). Improvement by at least two Snellen lines was achieved by 25% with 12.5% improving to 20/100 or better. Intracranial haemorrhage post IVT occurred in 1/13 (7.6%). The median time from onset of visual loss to IAT was 335 minutes. Improvement by at least two Snellen lines was achieved by 42%. No difference in 3-month VA was noted between patients that received thrombolysis, either alone (n = 8) or combined with other therapies, and those that received conservative therapies. Our results suggest that the management of acute CRAO remains heterogeneous. The lack of obvious benefit of thrombolysis in our small series supports the need for randomizsd clinical trials comparing thrombolysis to placebo to guide hyperacute CRAO management.

Safety and Efficacy of Selective Intra-arterial Thrombolysis for Central Retinal Artery Occlusion

PURPOSE

The purpose of this study was to determine the efficacy and safety of selective intra-arterial thrombolysis in patients with central retinal artery occlusion (CRAO).

METHODS

Medical records for 44 eyes of 44 patients diagnosed with acute non-arteritic CRAO and thrombolysis between October 2010 and February 2019 were analyzed retrospectively. Based on visual acuity, fundoscopic findings, and fluorescein angiography, the patients were classified into three stages: incomplete, subtotal, and total. The perfusion state using the best-corrected visual acuity (BCVA), arm to retina time, and arteriovenous passage times, after 1 month, 6 months, and at the final visit after the procedure, were compared with baseline readings.

RESULTS

Improvement of visual acuity was confirmed in 31 out of 44 patients (70.45%). The mean BCVA of 44 patients changed from 1.65 ± 0.78 logarithmic minimum angle of resolution (logMAR) at the first visit to 1.18 ± 0.91 logMAR at the last visit (p = 0.114). The BCVA according to CRAO stage was 0.08 ± 0.11 logMAR for the incomplete stage at the first visit, 0.06 ± 0.05 logMAR (p = 0.933) 1 month after the procedure, and 0.05 ± 0.07 logMAR (p = 0.933) at the last visit. In the subtotal stage, the results were 1.81 ± 0.54 logMAR at the first visit, 1.63 ± 0.76 logMAR (p = 0.035) 1 month after the procedure, and 1.36 ± 0.85 logMAR (p = 0.014) at the last visit. For the total stage of BCVA, the result at the first visit was 2.36 ± 0.25 logMAR, and it was 2.30 ± 0.30 logMAR (p = 0.510) 1 month after the procedure, and 2.42 ± 0.30 logMAR (p = 0.642) at the last visit. Reperfusion was observed in 40 patients out of the 44 (90.91%).

CONCLUSIONS

Selective intra-arterial thrombolysis can be helpful in patients with subtotal CRAO in terms of visual improvement and retinal arterial reperfusion.

The Retrobulbar Spot Sign and Prominent Middle Limiting Membrane as Prognostic Markers in Non-Arteritic Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is characterized by the sudden, painless loss of vision. Typical sonographic and optic coherence tomography (OCT) findings are a retrobulbar spot sign and prominent middle limiting membrane (p-MLM) sign. It remains uncertain whether the retrobulbar spot sign alone or coinciding with the appearance of p-MLM sign is a prognostic marker for visual acuity and the development of secondary retinal ischemia after CRAO. In our prospective cohort study, we included patients with a non-arteritic central artery occlusion < 4 weeks. We examined the following parameters at prespecified time points: ultrasound examination of orbital cavity, Spectral Domain-OCT examination, visual acuity test, and fundoscopy and ultra-widefield angiography to diagnose retinal vascularization. The presence of p-MLM sign in SD-OCT after CRAO was accompanied by significantly better vision during the first four weeks (2.3 (IQR 0.75) vs. 2.6 (IQR 0.33); p = 0.006). Moreover, the spot sign seems to be a prognostic factor for developing secondary retinal ischemia (8 (100%) vs. 0 (0%); p = 0.036). A retrobulbar spot sign seems to be a negative prognostic factor and is associated with secondary retinal ischemia, whereas a p-MLM sign is a somewhat positive prognostic factor for visual acuity.

Efficacy of YAG Laser Embolysis in Retinal Artery Occlusion

Objective:

To compare the anatomical and functional success between conventional medical method and Neodymium-Doped Yttrium Aluminum Garnet (Nd:YAG) laser embolysis in retinal artery occlusion.

Methods:

This randomized control trial was conducted at Armed Forces Institute of Ophthalmology (AFIO) Rawalpindi from July 2018 to May 2020. A total of 14 eyes of 14 patients were received with fovea involving branch or hemiretinal artery occlusion within 24 hours of onset of symptoms. They were divided randomly in two groups. Initial treatment was given to all cases, and seven eyes received Nd:YAG laser treatment for embolysis. Both groups were analysed for anatomical success (reperfusion) and functional success (defined as improvement in visual acuity to better than 6/60 on Snellen’s visual acuity chart from baseline visual acuity).

Results:

In conventional group, anatomical success was achieved in 2 (28.6%) eyes, while significant visual improvement was seen in 3 (42.8%) eyes. In Nd:YAG laser embolysis group, anatomical success was achieved in 5 (71.4%) eyes, while significant visual improvement was seen in 6 (85.7%) eyes. All eyes which showed functional improvement underwent Nd:YAG laser embolysis within 6 hours of onset of symptoms.

Conclusions:

Nd: YAG laser embolysis is more effective in management of fovea threatening retinal artery occlusion, as compared to conventional medical treatment, if performed within six hours of onset of symptoms.

Intra-Arterial Thrombolysis for Central Retinal Artery Occlusion

Introduction

Central retinal artery occlusion is an ophthalmic emergency which typically causes acute, painless visual loss. Several conservative treatment options are practiced with little benefit. Thrombolysis as a therapeutic option has gathered interest as well as controversy. This paper aims at reviewing the relevant literature to assess the efficacy and safety of intra-arterial thrombolysis for acute central retinal artery occlusion.

Methods

A review of the literature was conducted. Keywords included “intra-arterial thrombolysis” or “intra-arterial fibrinolysis” in combination with “central retinal artery occlusion” or “CRAO”. A Cochrane Database search was performed for randomised control trials, systematic reviews and meta-analyses using the same keywords.

Results

Twenty-eight studies were identified which included case reports, case series, case-control studies and 1 randomised control trial: the European Assessment Group for Lysis in the Eye Study. Improvement in vision was measured using different methods and at different time points. The findings of these studies generally favour an effect towards intra-arterial thrombolysis however there are many limitations. Additionally, the European Assessment Group for Lysis in the Eye Study showed lack of effect in intra-arterial thrombolysis vs conservative measures.

Conclusion

Current evidence is not sufficient to recommend intra-arterial thrombolysis due to the variability of visual improvement within retrospective studies, heterogeneity in treatment regimens between studies and adverse effects. Intra-arterial thrombolysis may have a role in patients presenting early, particularly if they have monocular vision, after discussion of the risks and benefits. Further high-quality trials assessing the clinical efficacy of intra-arterial thrombolysis may shed more light on this topic.