Management of Central Retinal Artery Occlusion: A Scientific Statement From the American Heart Association

Retinal artery occlusion after ophthalmic surgery under regional anaesthesia: A narrative review

Two recent cases of central retinal artery occlusion under otherwise uncomplicated sub-Tenon's block that resulted in significant visual loss after cataract surgery prompted us to undertake a literature review of such cases. We identified 97 cases of retinal artery occlusion after ophthalmic surgery under regional anaesthesia that had no immediate signs of block-related complications. These occurred after various intraocular (87%) and extraocular (13%) operations, across a wide range of ages (19-89 years) on patients with (59%) or without (39%) known risk factors. The anaesthetic techniques included 40 retrobulbar blocks, 36 peribulbar blocks, 19 sub-Tenon's blocks, one topical anaesthetic and one unspecified local anaesthetic. Different strengths of lidocaine, bupivacaine, mepivacaine and ropivacaine, either alone or in various combinations, were used. The details of the anaesthetic techniques were often incomplete in the reports, which made comparison and analysis difficult. Only nine cases had their cause (optic nerve sheath injury) identified, while the mechanism of injury was unclear in the remaining patients. Various mechanisms were postulated; however, the cause was likely to be multifactorial due to patient, surgical and anaesthetic risk factors, especially in those with compromised retinal circulation. As there were no definite risk factors identified, no specific recommendations could be made to avoid this devastating outcome. We have provided rationales for some general considerations, which may reduce this risk, and propose anaesthetic options for ophthalmic surgery on the fellow eye if required, based both on our literature review and our personal experience.

A Review of Current Literature on Central Retinal Artery Occlusion: Its Pathogenesis, Clinical Management, and Treatment

The ocular analogue of a cerebral stroke is central retinal artery occlusion (CRAO), a medical emergency concerning the eyes. Most patients experience substantial acute vision loss with a visual acuity of 20/400 or worse, resulting in decreased quality of life (QoL) and decreased functional ability. An impending cerebral stroke and ischemic heart disease are also more likely. The four distinct clinical entities that make up CRAO are non-arteritic CRAO, transitory non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, and arteritic CRAO. Depending on the CRAO type, clinical traits, visual results, and treatment all vary greatly. Contrary to current belief, there is a spontaneous improvement in the optical field and vision, mainly in the first week. The likelihood of instinctive development in optical acuity in the first seven days varies greatly. The pathogenesis, epidemiology, and medical features of CRAO will be described in this review, along with present and potential management future options.

Association of sodium-glucose cotransporter-2 inhibitors and the risk of retinal vascular occlusion: A real-world retrospective cohort study in Taiwan

AIMS

Sodium-glucose cotransporter-2 inhibitors (SGLT2is) are proposed to alleviate the development of inflammatory eye diseases. However, the association between SGLT2i and retinal vascular occlusion remains unclear. Therefore, this study aims to explore the effects of SGLT2i on the incidence of retinal vascular occlusion.

MATERIALS AND METHODS

This retrospective cohort study analysed electronic medical records data from the largest multi-institutional database in Taiwan. Individuals who initiated SGLT2is and dipeptidyl peptidase 4 inhibitors (DPP4is) between 2016 and 2019 were included in our analysis. To conduct a homogenous comparison, inverse probability of treatment weighting with propensity scoring was employed. The primary outcome was retinal vascular occlusion, and the secondary outcomes were retinal vascular occlusion-related complications (macular oedema, vitreous haemorrhage, and tractional retinal detachment) and conditions requiring vitreoretinal intervention (intravitreal injection, retinal laser therapy, and vitrectomy).

RESULTS

In total, 12,074 SGLT2i users and 39,318 DPP4i users were included. The incidence rate of retinal vascular occlusion in the SGLT2i and DPP4i groups was 1.2 (95% confidence interval [CI], 0.9-1.4) and 1.6 (95% CI, 1.3-1.8) events per 1000 person-years, respectively, which yielded a subdistribution hazard ratio (SHR) of 0.74 (95% CI, 0.55-0.99). Similar risk reductions were observed in the retinal vascular occlusion-related complications (SHR, 0.76; 95% CI, 0.69-0.84) and conditions requiring vitreoretinal intervention (SHR, 0.84; 95% CI, 0.77-0.94).

CONCLUSIONS

In this multi-institutional study in Taiwan, SGLT2i use was associated with a reduced risk of retinal vascular occlusion. Further prospective studies are required to ascertain this association.

Systematic review of the ophthalmic complications of robotic-assisted laparoscopic prostatectomy

This study aims to review ophthalmic injuries sustained during of robotic-assisted laparoscopic prostatectomy (RALP). A search of Medline, Embase, Cochrane and grey literature was performed using methods registered a priori. Eligible studies were published 01/01/2010-01/05/2023 in English and reported ophthalmic complications in cohorts of > 100 men undergoing RALP. The primary outcome was injury incidence. Secondary outcomes were type and permanency of ophthalmic complications, treatments, risk factors and preventative measures. Nine eligible studies were identified, representing 100,872 men. Six studies reported rates of corneal abrasion and were adequately homogenous for meta-analysis, with a weighted pooled rate of 5 injuries per 1000 procedures (95% confidence interval 3-7). Three studies each reported different outcomes of xerophthalmia, retinal vascular occlusion, and ophthalmic complications unspecified in 8, 5 and 2 men per 1000 procedures respectively. Amongst identified studies, there were no reports of permanent ophthalmic complications. Injury management was poorly reported. No significant risk factors were reported, while one study found African-American ethnicity protective against corneal abrasion (0.4 vs. 3.9 per 1000). Variables proposed (but not proven) to increase risk for corneal abrasion included steep Trendelenburg position, high pneumoperitoneum pressure, prolonged operative time and surgical inexperience. Compared with standard of care, occlusive eyelid dressings (23 vs. 0 per 1000) and foam goggles (20 vs. 1.3 per 1000) were found to reduce rates of corneal abrasion. RALP carries low rates of ophthalmic injury. Urologists should counsel the patient regarding this potential complication and pro-actively implement preventative strategies.

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.

Thrombolysis for central retinal artery occlusion: An individual participant-level meta-analysis

BACKGROUND

Whether thrombolysis improves outcomes in non-arteritic central retinal artery occlusion (naCRAO) is uncertain. We aimed to evaluate the rate of visual recovery after intra-venous thrombolysis (IVT) or intra-arterial thrombolysis (IAT) administration of tissue plasminogen activator (tPA) or urokinase among patients with naCRAO and explore the parameters affecting the final visual acuity (VA).

AIM

We systematically searched six databases. Logarithm of the minimum angle of resolution (logMAR) and VA of ⩾20/100 were used to quantify visual recovery. To explore the role of other factors on visual recovery, we defined two models for studies with aggregated data (designs 1 and 2) and 16 models for individual participant data (IPD, models 1-16).

SUMMARY OF REVIEW

We included data from 771 patients out of 72 publications in nine languages. Visual improvement for ⩾0.3 logMAR was reported in 74.3% of patients who received IVT-tPA within 4.5 h (CI: 60.9-86.0%; unadjusted rate: 73.2%) and 60.0% of those who received IAT-tPA within 24 h (CI: 49.1-70.5%; unadjusted rate: 59.6%). VA of ⩾20/100 was observed among 39.0% of patients after IVT-tPA within 4.5 h and 21.9% of those with IAT-tPA within 24 h. IPD models highlighted the association between improved visual outcomes and VA at presentation, at least 2 weeks follow-up before reporting the final VA, antiplatelet therapy, and shorter symptom onset to thrombolysis window.

CONCLUSION

Early thrombolytic therapy with tPA is associated with enhanced visual recovery in naCRAO. Future studies should refine the optimum time window for thrombolysis in naCRAO.

A case series on treatment of central and branch retinal artery occlusion with intravenous tenecteplase: Tenecteplase for retinal artery occlusions

OBJECTIVES

Central and branch retinal artery occlusions are disabling ischemic strokes of the retina for which established acute treatments are lacking. This is the first published report of the use of intravenous tenecteplase (TNK) for retinal artery occlusion, in which we describe the clinical course of four patients with central retinal artery occlusion (CRAO) and one patient with branch retinal artery occlusion (BRAO).

MATERIALS AND METHODS

Patients were retrospectively recruited to the study from two stroke centers. Clinical course was determined from review of electronic medical records. The primary outcomes of interest were short and long term complications as well as visual acuity at presentation and at any subsequent follow up.

RESULTS

There were no hemorrhagic complications. None of the four patients with CRAO experienced functional visual recovery (defined as improvement to 20/100 or better). The patient with BRAO had functional visual recovery.

CONCLUSIONS

Intravenous TNK may be a safe and reasonable treatment for CRAO and BRAO.

Addressing retinal hypoxia: pathophysiology, therapeutic innovations, and future prospects

Retinal hypoxia stands as a pivotal yet often underappreciated factor in the etiology and progression of many retinal disorders such as glaucoma, hypertensive retinopathy, diabetic retinopathy, retinal vein occlusions, and retinal artery occlusions. Current treatment methodologies fail to directly address the underlying pathophysiology of hypoxia and aim to improve ischemia through alternative methods. In this review, we discuss the critical role of retinal hypoxia in the pathogenesis of various retinal diseases and highlight the need for innovative therapeutic strategies that address the root cause of these conditions. As our understanding of retinal hypoxia continues to evolve, the emergence of new technologies holds the promise of more effective treatments, offering hope to patients at risk of vision loss.

Atrial fibrillation as a novel risk factor for retinal stroke: A protocol for a population-based retrospective cohort study

Central retinal artery occlusion (CRAO; retinal stroke or eye stroke) is an under-recognized, disabling form of acute ischemic stroke which causes severe visual loss in one eye. The classical risk factor for CRAO is ipsilateral carotid stenosis; however, nearly half of patients with CRAO do not have high-grade carotid stenosis, suggesting that other cardiovascular risk factors may exist for CRAO. Specifically, prior studies have suggested that cardioembolism, driven by underlying atrial fibrillation, may predispose patients to CRAO. We describe the design of an observational, population-based study in this protocol. We evaluate two specific objectives: 1) To determine if atrial fibrillation is an independent risk factor for CRAO after adjusting for medical and cardiovascular risk; 2) To determine if use of oral anticoagulation can modify the risk of CRAO for patients with atrial fibrillation. This protocol lays out our strategy for cohort definition, case and control definition, comorbidity ascertainment, and statistical methods.

Prevalence and risk factors of ischemic monocular vision loss and concurrent brain ischemia

INTRODUCTION

We performed a retrospective cohort study to identify predictors of concurrent asymptomatic brain ischemia in patients with ischemic monocular vision loss.

PATIENTS AND METHODS

An inpatient database research of admissions to the Helios University Hospital Wuppertal, Germany between 01/2016 and 12/2020 was conducted. Inclusion criteria were confirmed diagnosis of transient monocular vision loss (MVL), retinal artery occlusion (RAO), and magnetic resonance imaging (MRI) of the brain within 10 days of MVL. Silent brain ischemia (SBI) was defined as diffusion restrictions with corresponding reduced apparent diffusion coefficient in MRI and an absence of neurological deficits besides those complying with MVL in clinical examination. The prevalence and cardiovascular predictors of SBI were analyzed with logistic regression and an artificial neural network.

RESULTS

One hundred fourteen out of 475 patients treated with monocular vision loss were included in this study. The mean age was 67.7 ± 13.6 years. 48.2% were male and 47.4% had RAO. MRI scan of the brain was performed after 3.9 ± 2.3 days and detected SBI in 17%. Age ⩾67 years, cardiac etiology of MVL, and cerebral ischemia in medical history were revealed as predictors of SBI in MRI.

CONCLUSIONS

Patients older than 66 years, with a suspected cardiac embolism as the cause of RAO and previous cerebral ischemia, are more likely to present SBI in cerebral MRI. Therefore, MR imaging, particularly in these patients, can be useful.

Statin Treatment on Cardiovascular Risk After Retinal Artery Occlusion: A Historical Cohort Study

INTRODUCTION

Retinal artery occlusion (RAO) is a major cause of acute visual loss and patients with RAO have an increased risk for subsequent cardiovascular events. However, there is little evidence of whether the use of statins is associated with the prevention of cardiovascular events in patients with RAO. We investigated whether statin treatment in patients with RAO is associated with a lower risk of cardiovascular events.

METHODS

This study was a historical cohort study with nested case-control analysis. Using the nationwide health insurance claims database in Korea, we retrospectively established a cohort of newly diagnosed RAO patients without prior cardiovascular events between January 2008 and March 2020. We defined the case group as those who had cardiovascular events (stroke or myocardial infarction) and the control group as RAO patients without primary outcome matched by sex, age, comorbidities, and duration of follow-up (1:2 incidence density sampling). Conditional logistic regression was performed.

RESULTS

Among 13,843 patients newly diagnosed with RAO, 1030 patients had cardiovascular events (mean follow-up period of 6.4 ± 3.7 years). A total of 957 cases were matched to 1914 controls. Throughout the study period, the proportion of patients taking statin was less than half. Statin treatment after RAO was associated with a low risk of cardiovascular events (adjusted OR, 0.637; 95% CI 0.520-0.780; P < 0.001). A longer duration of statin exposure was associated with a lower cardiovascular risk.

CONCLUSIONS

In patients with newly diagnosed RAO, treatment with statins, particularly long-term use, was associated with a low risk of future cardiovascular events.

Neuro-ophthalmology Emergency Department and Inpatient Consultations at a Large Academic Referral Center

PURPOSE

Prompt neuro-ophthalmology consultation prevents diagnostic errors and improves patient outcomes. The scarcity of neuro-ophthalmologists means that the increasing outpatient demand cannot be met, prompting many emergency department (ED) referrals by non-neuro-ophthalmologists. We describe our quaternary care institution's ED and inpatient neuro-ophthalmology consultation patterns and patient outcomes.

DESIGN

Prospective observational study.

PARTICIPANTS

Consecutive neuro-ophthalmology ED and inpatient consultation requests over 1 year.

METHODS

We collected patient demographics, distance traveled, insurance status, referring provider details, consultation question, final diagnosis, complexity of consultation, time of consultation, and need for outpatient follow-up.

MAIN OUTCOME MEASURES

Consultation patterns and diagnoses, complexity, and follow-up.

RESULTS

Of 494 consecutive adult ED and inpatient neuro-ophthalmology consultations requested over 1 year, 241 of 494 consultations (49%) occurred at night or during weekends. Of ED consultations (322 of 494 [65%]), 127 of 322 consultations (39%) occurred during weekdays, 126 of 322 consultations (39%) occurred on weeknights, and 69 of 322 consultations (22%) occurred on weekends or holidays. Of 322 ED consultations, 225 of 322 consultations (70%) were patients who initially sought treatment in the ED with a neuro-ophthalmic chief symptom. Of the 196 patients sent to the ED by a health care professional, 148 patients (148/196 [76%]) were referred by eye care specialists (74 optometrists and 74 ophthalmologists). The most common ED referral questions were for papilledema (75 of 322 [23%]) and vision loss (72 of 322 [22%]). A total of 219 of 322 patients (68%) received a final active neuro-ophthalmic diagnosis, 222 of 322 patients (69%) were cases of high or very high complexity, and 143 of 322 patients (44%) required admission. Inpatient consultations (n = 172) were requested most frequently by hospitalists, including neurologists (71 of 172 [41%]) and oncologists (20 of 172 [12%]) for vision loss (43 of 172 [25%]) and eye movement disorders (36 of 172 [21%]) and by neurosurgeons (58 of 172 [33%]) for examination for mass or a preoperative evaluation (19 of 172 [11%]). An active neuro-ophthalmic diagnosis was confirmed in 67% of patients (116 of 172). Outpatient neuro-ophthalmology follow-up was required for 291 of 494 patients (59%).

CONCLUSIONS

Neuro-ophthalmology consultations are critical to the diagnosis and management in the hospital setting. In the face of a critical shortage of neuro-ophthalmologists, this study highlights the need for technological and diagnostic aids for greater outpatient access.

FINANCIAL DISCLOSURE(S)

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

Risk of Stroke, Myocardial Infarction, and Death After Retinal Artery Occlusion

Importance

Patients with retinal artery occlusions (RAOs) are recommended to have emergent stroke workup, although the true risk of death and subsequent vascular events post-RAO is not clear.

Objective

To determine short-term and long-term rates of stroke, myocardial infarction (MI), and death in patients after RAO compared with a control cohort.

Design, Setting, and Participants

This retrospective cohort study used aggregated electronic health records from January 1, 2003, through April 14, 2023, from TriNetX, a network with data from more than 111 million patients. Patients with RAO and a cataract control group were identified and matched for age, sex, race, and comorbidities, including hypertension, diabetes, hyperlipidemia, and smoking status. Patients were excluded if they had a stroke or MI within 2 years before the diagnosis of RAO or cataract.

Exposure

International Statistical Classification of Diseases and Related Health Problems, Tenth Revision, diagnosis code for RAO or age-related cataract.

Main Outcomes and Measures

Rate of death, stroke, and MI at 2 weeks, 30 days, 1 year, 5 years, and 10 years after RAO compared with matched controls.

Results

There were a total of 34 874 patients with at least 1 year of follow-up in the RAO cohort. The mean (SD) age at the RAO event was 66 (15.2) years. The rate of death after RAO diagnosis was higher than after cataract diagnosis at 2 weeks (0.14% vs 0.06%; relative risk [RR], 2.45; 95% CI, 1.46-4.12; risk difference [RD], 0.08%; 95% CI, 0.04%-0.13%; P < .001), 30 days (0.29% vs 0.14%; RR, 2.10; 95% CI, 1.49-2.97; RD, 0.15%; 95% CI, 0.08%-0.22%; P < .001), 1 year (3.51% vs 1.99%; RR, 1.78; 95% CI, 1.61-1.94; RD, 1.41%; 95% CI, 1.17%-1.66%; P < .001), 5 years (22.74% vs 17.82%; RR, 1.28; 95% CI, 1.23-1.33; RD, 4.93%; 95% CI, 4.17%-5.68%; P < .001), and 10 years (57.86% vs 55.38%; RR, 1.05; 95% CI, 1.02-1.07; RD, 2.47%; 95% CI, 1.25%-3.69%; P < .001). Risk of stroke after RAO was higher at 2 weeks (1.72% vs 0.08%; RR, 21.43; 95% CI, 14.67-31.29; RD, 1.64%; 95% CI, 1.50%-1.78%; P < .001), 30 days (2.48% vs 0.18%; RR, 14.18; 95% CI, 10.94-18.48; RD, 2.31%; 95% CI, 2.14%-2.47%; P < .001), 1 year (5.89% vs 1.13%; RR, 5.20; 95% CI, 4.67-5.79; RD, 4.64%; 95% CI, 4.37%-4.91%; P < .001), 5 years (10.85% vs 4.86%; RR, 2.24; 95% CI, 2.09-2.40; RD, 6.00%; 95% CI, 5.50%-6.50%; P < .001), and 10 years (14.59% vs 9.18%; RR, 1.59; 95% CI, 1.48-1.70; RD, 5.41%; 95% CI, 4.62%-6.21%; P < .001). Risk of MI after RAO was higher at 2 weeks (0.16% vs 0.06%; RR, 3.00; 95% CI, 1.79-5.04; RD, 0.11%; 95% CI, 0.06%-0.16%; P < .001), 30 days (0.27% vs 0.10%; RR, 2.61; 95% CI, 1.78-3.83; RD, 0.17%; 95% CI, 0.10%-0.23%; P < .001), 1 year (1.66% vs 0.97%; RR, 1.72; 95% CI, 1.51-1.97; RD, 0.59%; 95% CI, 0.42%-0.76%; P < .001), 5 years (6.06% vs 5.00%; RR, 1.21; 95% CI, 1.12-1.31; RD, 1.07%; 95% CI, 0.64%-1.50%; P < .001), and 10 years (10.55% vs 9.43%; RR, 1.12; 95% CI, 1.04-1.21; RD, 1.13%; 95% CI, 0.39%-1.87%; P = .003).

Conclusions and Relevance

This study showed an increased risk of death, stroke, and MI in patients with RAO at both short-term and long-term intervals after RAO compared with a matched control population diagnosed with cataract. These findings suggest a potential need for multidisciplinary evaluation and long-term systemic follow-up of patients post-RAO.

Long-term outcomes of intravenous fibrinolysis in central retinal artery occlusion

Central retinal artery occlusion (CRAO) is an ophthalmologic emergency that can lead to irreversible loss of vision. Intravenous thrombolysis (IVT) has been used experimentally for its treatment. Our study aimed to evaluate the effect of emergency IVT on CRAO and its impact on visual acuity outcomes. We conducted a retrospective observational study of patients with CRAO. A total of 46 patients with CRAO were analysed; 16 patients received IVT treatment (IVT group) while 30 did not (no-IVT group). Seven patients from the IVT group received IVT early, within 4.5 hours (h) after the onset of symptoms (early-IVT), and 9 patients received it beyond this timeframe (late-IVT). The median time-to-hospital was 8.5 h: 3 h for the IVT group and 24 h for the no-IVT group. The median time-to-treatment was 5 h. The median outcome of visual acuity was 0.05 in the early-IVT, 0.025 in the late-IVT, and 0.01 in the no-IVT group. Among patients who received IVT early, 86% exhibited significant visual improvement. This improvement was four-fold greater compared to all other groups (p = 0.040), including the late-IVT (p = 0.011) and no-IVT groups (p = 0.023). No complications of the treatment were reported. Our study confirms that the administration of IVT treatment for CRAO within the 4.5-h time window is both safe and effective.

Telemedicine for Acute Monocular Visual Loss: A Retrospective Large Telestroke Network Experience

Introduction: Central retinal artery occlusion (CRAO) is an under-recognized stroke subtype that may benefit from hyperacute reperfusion therapies. We aimed to evaluate the ability of telestroke activations to provide CRAO diagnosis and thrombolysis. Methods: This retrospective observational study investigates all encounters conducted for acute visual loss between 2010 and 2021 in our multicentric Mayo Clinic Telestroke Network. Demographics, time from visual loss to telestroke evaluation, ocular examination, diagnostic, and therapeutic recommendations were collected for CRAO subjects. Results: Out of 9,511, 49 encounters (0.51%) were conducted for an acute ocular complaint. Five patients had possible CRAO, and 4 presented within 4.5 h from symptom onset (range 1.5-5 h). None received thrombolytic therapy. All telestroke physicians recommended ophthalmology consultation. Conclusion: Current telestroke assessment of acute visual loss is suboptimal and patients eligible for acute reperfusion therapies may not be offered treatment. Teleophthalmologic evaluations and advanced ophthalmic diagnostic tools should complement telestroke systems.

Case report: acute isolated cilioretinal artery occlusion secondary to percutaneous coronary intervention

INTRODUCTION

This case report aims to describe in detail the acute isolated cilioretinal artery occlusion (CLRAO) secondary to complicated therapeutic percutaneous coronary intervention (PCI).

CASE DESCRIPTION

A 68-year-old Chinese man with coronary artery disease (CAD) complained of sudden, sharp chest pain. Coronary angiography revealed severe stenoses of the coronary arteries. The patient was then treated with PCI. One hour after the procedure, the patient presented with a sudden reduction in vision in the right eye. The patient was diagnosed with acute isolated CLRAO and treated with Salvia miltiorrhiza injections.

CONCLUSIONS

This is the report to provide a detailed description of acute isolated CLRAO secondary to therapeutic PCI treated with Salvia miltiorrhiza. The visual prognosis of the untreated patients is poor. Suitable management and prevention are essential for interventional cardiologists to prevent these complications.

Visual acuity assessment of central retinal artery occlusion patients with or without paracentral acute middle maculopathy via OCT-A

PURPOSE

The association between paracentral acute middle maculopathy (PAMM) and visual acuity in patients with central retinal artery occlusion (CRAO) is still unclear. The present study investigated the visual acuity of CRAO patients with and without PAMM.

METHODS

CRAO patients with PAMM or without PAMM were included. Optical coherence tomography angiography (OCT-A) was used to record the macular retinal thickness and density of shallow and deep vessels. The Best-corrected visual acuity (BCVA) was converted to a logarithm of the minimum angle of resolution (LogMAR) for statistical analysis.

RESULTS

There were 34 CRAO patients with PAMM (43.13%), other 30 CRAO patients without PAMM (46.87%). Compared with the no-PAMM group, PAMM group had better LogMAR BCVA (1.48 (0.49, 1.85) Vs. 1.85 (1.70, 1.96), P < 0.01). There was also a significant difference in retinal thickness of the central macular sulcus (328.00 (304.50-332.25) Vs. 352.50 (311.75-420.50), P = 0.01). A significant correlation between LogMAR BCVA and macular retinal thickness was found (r = 0.42; P < 0.01).

CONCLUSION

CRAO patients with PAMM had significantly better visual acuity and less macular edema. OCT-A can be used to distinguish different levels of damage due to CRAO.

Ophthalmologic Emergencies: Assessment and Management

There are an estimated 2-3 million emergency department (ED) visits in the United States for eye complaints. Although most patients who present to the ED have nontraumatic eye complaints, many seek treatment for eye trauma, which is a leading cause of unilateral blindness and vison impairment. Given the prevalence of eye-related emergencies, it is imperative that emergency care providers understand how to recognize and treat eye complaints to prevent permanent vision loss and disability. This article covers basic eye anatomy and physiology, discusses a systematic approach to the eye examination, and presents the evidence-based treatment of selected, common nonemergent and emergent eye complaints. For each complaint, essential history questions, examination techniques, differentials, and emergency management have been presented.

Central retinal artery occlusion in a young child affected by COVID-19: a first case report

BACKGROUND

Central retinal artery occlusion (CRAO) is an ophthalmic emergency, and its etiology is generally ascribed to vessel occlusion by a thrombus or embolus, eventually due to a hypercoagulable state. CRAO occurrence is described even in the pediatric population, but its incidence is very rare. SARS-CoV-2 infection has a multitude of presentations, and almost any organ may be involved including the ocular district. Cases of CRAO in patients affected by COVID-19 are reported in the literature in the adult population, but not in the pediatric one.

CASE PRESENTATION

We describe the case of a six-year-old otherwise healthy girl, who presented a sudden and complete bilateral vision loss after a one-day fever. All the clinical, ophthalmological, laboratory and instrumental investigations led to the diagnosis of a right CRAO and the suspicion of a contralateral posterior optic nerve affection. These manifestations could not be ascribed to any etiological condition apart from the documented ongoing mild SARS-CoV-2 infection. Treatment with anticoagulants and steroids was tried but the visual outcome was poor during the one-month hospitalization and at the last follow-up.

CONCLUSIONS

To the best of our knowledge, this is the first report of CRAO in the course of SARS-CoV-2 infection in the pediatric age. In our review of the literature, we found few cases of CRAO in adults with COVID-19; we highlighted differences in anamnestic, clinical, and interventional aspects and therefore we tried to summarize the state of the art on this topic to facilitate further studies. Even if rare, the prognosis of CRAO is poor and the thrombolytic treatment could be effective only if rapidly administered, so the disease suspicion should be high in a patient with sudden vision loss, also in pediatric age.

Sex differences in major adverse cardiovascular and cerebrovascular event risk among central retinal artery occlusion patients

To estimate the association between central retinal artery occlusion (CRAO) and major adverse cardiovascular and cerebrovascular events (MACCE), including their clinical characteristics, blood markers, and the contribution of CRAO to MACCE, as well as to assess any sex differences. This retrospective cohort study included continuous new-onset CRAO patients and 1:4 controls during the same period. Correlations of CRAO with the incidence of MACCE during follow-up and the sex-related differences were studied. One hundred and twenty-four CRAO patients and four hundred and ninety-six controls were enrolled. Neutrophil-to-lymphocyte ratio (NLR, P = 0.014) and high-sensitivity C-reactive protein (hs-CRP, P = 0.038) were tended to be higher in CRAO patients. After the follow-up period, 78 patients experienced MACCE. Multivariate Cox regression analysis showed that CRAO was a predictor of the occurrence of MACCE (HR 2.321, 95% CI 1.439-3.744, P = 0.001). Sex subgroups indicated that age, diabetes, current smoking, CRAO, NLR and hs-CRP increased the risk factor of MACCE in males (All P < 0.05) and CRAO, NLR, low-density lipoprotein cholesterol (LDL-C) and hs-CRP were independent influencing factors for females (All P < 0.05). New-onset CRAO significantly increases the probability of MACCE and is associated with a poor prognosis. The sex-related differences suggested that effective prevention of the occurrence of MACCE in high-risk patients requires that attention be given to individualized risk factors corresponding to sexes.

Visual Recovery in 2 Cases of Central Retinal Artery Occlusion Treated With Prompt Intra-ophthalmic Artery Fibrinolysis

BACKGROUND

Central retinal artery occlusion (CRAO) rapidly produces inner retinal ischemia and irreversible vision loss. Although many therapeutic interventions have been proposed, no interventions have proven effective in restoring vision in large randomized controlled trials and final visual outcome in most patients is very poor.

METHODS

Retrospective case series.

RESULTS

We describe 2 cases of CRAO occurring after uncomplicated cataract surgery under topical anesthesia and rapidly diagnosed. Both had very severe vision loss at presentation with dramatic improvement after intra-ophthalmic artery fibrinolysis administered 2.75 and 5.5 hours after symptom onset.

CONCLUSIONS

Sudden monocular vision loss is an ophthalmologic emergency as CRAO must be ruled out and if diagnosed, rapid intervention should be performed. Devastating vision loss can be prevented if interventional neuroradiology is trained and available on a 24-hour basis for administration of local intra-arterial thrombolysis.

Progress in central retinal artery occlusion: a narrative review

Central retinal artery occlusion (CRAO) is a catastrophic ophthalmic emergency that severely impairs a patient's visual function, often reducing visual acuity to counting fingers or worse. Progress in CRAO research has provided new information regarding its epidemiological characteristics and led to useful assessments through various ophthalmic examinations. Additional insights about CRAO have been gained through studies of its pathophysiological mechanisms, improving intervention timing and enhancing patient prognosis. Treatment for CRAO has evolved, particularly with assistance from surgical instruments and surgical robots. Although surgical treatment is now possible, this option is not widely recognized by ophthalmologists. Conservative therapies have limited benefits compared with the natural course of disease. Recently, pars plana vitrectomy plus endovascular surgery has received considerable interest among ophthalmologists because of its potential efficacy in the treatment of CRAO. Considering the inconsistencies in rationale and efficacy of CRAO treatment modalities, it is important to distinguish between treatment effects and the natural courses of various CRAO subclasses. This narrative review explores progress in CRAO epidemiology, pathophysiology, ophthalmic examination, and treatment.

Neovascular Glaucoma Complicating Central Retinal Artery Occlusion Despite Cilioretinal Artery Sparing

This case report aims to describe a case of unilateral central retinal artery occlusion (CRAO) with cilioretinal artery sparing, which was complicated by neovascular glaucoma (NVG). A 75-year-old Indian woman with underlying normal tension glaucoma presented with the sudden onset of painless generalized blurring of the right eye's vision for a week. Her right eye vision was hand motion with the presence of a right relative afferent pupillary defect. Fundus examination revealed retinal whitening over the macula sparing the papillomacular bundle with generalized retinal arteriolar attenuation, which was suggestive of right CRAO with cilioretinal artery sparing. Systemic examination revealed high blood pressure (175/75 mmHg) without ocular bruit or audible murmur on auscultation. Optical coherence tomography of the macula showed inner retinal thickening over the temporal macula. Ultrasound carotid Doppler and computed tomography angiography of the carotid showed more than 75% stenosis over the right distal internal carotid artery. Unfortunately, she developed rubeosis iridis over her right eye two weeks after her presentation, which required pan-retinal photocoagulation. She subsequently progressed to NVG, requiring maximum anti-glaucoma medications to stabilize intraocular pressure. In conclusion, CRAO is a sight-threatening medical emergency. Thorough investigations are required to determine the underlying cause so that early intervention can be done to reduce the risk of a similar attack in the fellow eye and the risk of a cerebrovascular event or cardiac ischemia, which could be life-threatening. The presence of a cilioretinal artery does not prevent ocular neovascularization in CRAO. Hence, patients should also be closely monitored after the initial diagnosis to prevent devastating complications such as NVG.

High prevalence of thrombophilic risk factors in patients with central retinal artery occlusion

INTRODUCTION

Central retinal artery occlusion (CRAO) is a common cause of blindness and visual morbidity. In the majority of cases, it is related to thrombotic embolism. Nevertheless, the role of inherited or acquired thrombophilic risk factors in CRAO pathogenesis has not been comprehensively studied.

METHODS

In 126 CRAO patients (66 [52.4%] men, median age 55 [range: 18-80] years) and 107 matched controls (56 [52.3%] men, median age 53 [range: 34-78] years) we evaluated classical atherosclerotic risk factors, including serum lipid profile and glucose level, analyzed intima-media complex thickness (IMT) of external carotid arteries, and performed transthoracic echocardiography. Furthermore, we established the prevalence of inherited and acquired thrombophilic risk factors, such as factor V Leiden (FVL) and prothrombin 20210 G/A genetic variants, plasma activity of factor (F) VIII, protein C and antithrombin activity, and free protein S levels. We also assessed the presence of antiphospholipid antibodies (APLA) and evaluated blood homocysteine in all enrolled subjects. Additionally, we estimated the occurrence of Val34Leu polymorphism of the A subunit of coagulation factor XIII (FXIII-A) in both groups as a potential thrombosis-protecting factor.

RESULTS

Among traditional atherosclerotic risk components, obesity/overweight and hypercholesterolemia were the most common in the CRAO group and occurred in 103 (81.7%) and 85 (67.5%) patients, respectively. CRAO patients also had elevated IMT and altered echocardiographic parameters, indicating diastolic cardiac dysfunction. In thrombophilia investigations, at least one laboratory risk factor occurred in 72.2% (n = 91) of CRAO patients, with APLA as the most frequent, detected in 38.1% (n = 48) of them (almost seven times more frequent than in controls, p < 0.001). Deficiencies in protein C activity and free protein S levels were also common in the CRAO group, reported in 17.5% (n = 22) and 19.8% (n = 25) of patients, respectively. Interestingly, among two analyzed prothrombotic genetic variants, only the FVL was related to CRAO, with the allelic frequency 2.4 times more prevalent than in controls (p = 0.044). Finally, the CRAO group was characterized by hyperhomocysteinemia, almost twice as common as in controls (p = 0.026). Antithrombin deficiency, elevated FVIII, and FXIII-A Val34Leu polymorphism were not associated with CRAO.

CONCLUSIONS

Our findings suggest that thrombophilia plays a vital role in the pathogenesis of CRAO. Thus, proper laboratory screening should be considered in the primary and secondary prevention of those episodes, with implementing appropriate therapy as needed.

Intravenous Thrombolysis for Central Retinal Artery Occlusion: A Look at the Literature for the Emergency Medicine Physician

Central retinal artery occlusion (CRAO) is a subtype of ischemic stroke and true ocular emergency presenting with acute, painless, monocular vision loss. Typical findings include poor visual acuity (VA), impaired color vision, relative afferent pupillary defect, and on fundoscopic evaluation, retinal edema, cherry red spot, and occasionally visualization of retinal artery emboli. While there are no proven treatments for CRAO, options include orbital massage, hyperbaric oxygen therapy, and intra-arterial or intravenous thrombolysis (IVT). This study reviews the current literature on the efficacy of IVT for patients affected by acute, symptomatic CRAO and provides an up-to-date, evidence-based background for emergency physicians (EPs) who evaluate and manage these patients.

Retinal stroke: research models, targets and experimental drugs

INTRODUCTION

Retinal artery occlusion (RAO), often caused by a microembolus and resulting in inner retinal ischemia, could be considered as the retinal analog to cerebral stroke. Although several therapeutic targets have been suggested in animal models of retinal ischemia and several potential treatments have been evaluated on small series of patients, central retinal artery occlusion (CRAO) is still rarely treatable in clinical practice.

AREAS COVERED

Here, we review several animal models of RAO, including increased intraocular pressure, laser, vasoconstriction, embolization and clamp. We also review the pathogenic mechanisms that contribute to cell death cascades during ischemia, and the therapeutic strategies targeting these events. These strategies aim to restore blood flow by fibrinolysis, increase the oxygen or glucose supply, decrease the energy demands, restrict ionic leak fluxes or reduce the detrimental effects of glutamate, calcium and free radicals. The current literature suggests that tPA treatment could be effective for CRAO.

EXPERT OPINION

Eye care professionals must make a rapid and accurate diagnosis and immediately refer patients with acute retinal stroke to specialized centers. CRAO management should also be facilitated by developing local networks to encourage collaboration among ophthalmologists, retina specialists and stroke neurologists.

Morphometric Analysis of the Ophthalmic and Central Retinal Arteries via the Endoscopic Endonasal Trans-ethmoidal Approach: Surgical Relevance of Vascular Components Within the Medial Intraconal Zones

BACKGROUND

The endoscopic endonasal approach (EEA) offers a minimally invasive route to treat medial intraconal space (MIS) lesions. Understanding the configuration of the ophthalmic artery (OphA) and the central retinal artery (CRA) is crucial.

METHODS

An EEA to the MIS was performed on 30 orbits. The description of the intraorbital part of the OphA was divided into 3 segments and classified as type 1 and type 2 and the MIS was divided into three surgical zones (A, B, C). The CRA's origin, course, and point of penetration (PP) were analyzed. The relationship between the position of the CRA in the MIS and the OphA type was analyzed.

RESULTS

The OphA type 2 was present in 20% of specimens. The site of origin of the CRA from the OphA was found on the medial surface in type 1 and on the lateral surface of type 2. The point of penetrationof the central retinal arterywas found in 87% of the specimens on the inferomedial surface, just anterior to the inferior muscular trunk, at an average distance of 9.5 mm ± 1 from the globe and 17 mm ± 1.5 from the AZ. The presence of the CRA in Zone C was associated only with OphA type 1.

CONCLUSIONS

OphA type 2 is a common finding and can compromise the feasibility of an EEA to the MIS. A detailed preoperative analysis of the OphA and CRA should be conducted prior to approaching the MIS due to the implications of the anatomical variations that can compromise safe intraconal maneuverability during an EEA.

Successful Mechanical Thrombectomy for Isolated Internal Carotid Artery Occlusion in a Patient with Monocular Blindness: A Case Report

We report a rare case of isolated internal carotid artery occlusion complicated by central retinal artery occlusion that was successfully treated with mechanical thrombectomy for internal carotid artery occlusion. A 59-year-old man visited the emergency room because of right monocular blindness. Magnetic resonance imaging showed multiple acute small embolic infarctions in the right frontal lobe, and magnetic resonance angiography revealed right internal carotid artery occlusion without the associated occlusion of the circle of Willis, which indicates the patency of the anterior and middle cerebral arteries. An electrocardiogram showed atrial fibrillation. Therefore, we performed mechanical thrombectomy with a stent retriever under continuous manual aspiration with a balloon-guiding catheter and confirmed complete recanalization, anterograde flow in the right ophthalmic artery, and retinal brush. The procedure was completed without complications, and the patient noticed an improvement in visual acuity immediately after the procedure. When a patient with atrial fibrillation complains of monocular blindness, it is important to consider internal carotid artery occlusion due to cardioembolism, to perform an examination promptly, and to consider early treatment, including mechanical thrombectomy.

Monocular Vision Loss in a Patient With Earache and Night Sweats

A 62-year-old patient with a history of painless vision loss in her right eye, right ear pain and fullness, discomfort over her frontal and maxillary sinuses, nasal congestion without discharge, drenching night sweats, cramps in her quadriceps, and weight loss presented to the ophthalmology department. Examination revealed normal tympanic membranes and a dry but otherwise normal nasal mucosa on flexible endoscopy. What would you do next?

Characterization of Oxygen Nanobubbles and In Vitro Evaluation of Retinal Cells in Hypoxia

Purpose

Vein or artery occlusion causes a hypoxic environment by preventing oxygen delivery and diffusion to tissues. Diseases such as retinal vein occlusion, central retinal artery occlusion, or diabetic retinopathy create a stroke-type condition that leads to functional blindness in the effected eye. We aim to develop an oxygen delivery system consisting of oxygen nanobubbles (ONBs) that can mitigate retinal ischemia during a severe hypoxic event such as central retinal artery occlusion.

Methods

ONBs were synthesized to encapsulate oxygen saturated molecular medical grade water. Stability, oxygen release, biocompatibility, reactive oxygen species, superoxide, MTT, and terminal uridine nick-end labeling assays were performed. Cell viability was evaluated, and safety experiments were conducted in rabbits.

Results

The ONBs were approximately 220 nm in diameter, with a zeta potential of -58.8 mV. Oxygen release studies indicated that 74.06 µg of O2 is released from the ONBs after 12 hours at 37°C. Cell studies indicated that ONBs are safe and cells are viable. There was no significant increase in reactive oxygen species, superoxide, or double-stranded DNA damage after ONB treatment. ONBs preserve mitochondrial function and viability. Histological sections from rabbit eyes indicated that ONBs were not toxic.

Conclusions

The ONBs proposed have excellent oxygen holding and release properties to mitigate ischemic conditions in the retina. They are sterile, stable, and nontoxic.

Translation Relevance

ONB technology was evaluated for its physical properties, oxygen release, sterility, stability, and safety. Our results indicate that ONBs could be a viable treatment approach to mitigate hypoxia during ischemic conditions in the eye upon timely administration.

Retinal Artery Occlusion as an Early Indicator of Macrovascular Complications in Diabetes

BACKGROUND

A characteristic of the retinal circulation is that arterial occlusion is embolic or secondary to vasculitis but rarely or never due to in situ atherosclerosis. Therefore, retinal artery occlusion suggests the presence of cardiac or large-vessel disease outside the eye. This cohort study examined the general risk of macrovascular disease in individuals with diabetes, with or without retinal artery occlusion.

METHODS

We retrieved data on 992 subjects with incident retinal artery occlusion and preexisting diabetes, registered in Denmark between January 1, 2000, and December 31, 2018. Each retinal artery occlusion subject was matched for age, sex, and diabetes duration, with 5 control subjects with diabetes but without retinal artery occlusion. We performed survival analyses to compare the risk of extraocular macrovascular disease between the 2 groups in a 5-year follow-up.

RESULTS

After 1 year, the incidence of macrovascular disease in subjects with retinal artery occlusion was approximately 21 per 100 person-years (95% confidence interval [CI]: 18.11-24.29), compared to 6.25 per 100 patient-years (95% CI: 5.57-7.00) in those without retinal artery occlusion. After 5 years, the cumulative incidences of macrovascular disease were 51.2% (95% CI: 47.9-54.7%) and 29.4% (95% CI: 28.0-30.8%) in patients with diabetes with or without retinal artery occlusion, respectively. Hazard rate ratios were 3.36 (95% CI: 2.79-4.05) after 1 year and 2.27 (95% CI: 2.04-2.53) after 5 years.

CONCLUSION

Among individuals with diabetes, those diagnosed with retinal artery occlusion had a higher general risk of macrovascular complications for at least 5 years after the occlusion event compared with those without retinal artery occlusion.

Central Retinal Artery Occlusion in a Young Patient With a Hidden Unusual Sickle Cell Trait

Sickle cell trait is considered a benign condition. Ophthalmic manifestations are infrequent but can result in significant visual deterioration. We present a case of a 33-year-old male, not known to have any medical illnesses, who presented to the ophthalmological emergency room complaining of a sudden onset of painless and profound left eye vision loss for 12 hours. The patient denied any medication use, past eye trauma, or surgery. On detailed ophthalmologic examination, the best-corrected visual acuity (BCVA) was 20/20 in the right eye and hand movement in the left eye. Dilated fundus examination of the left eye showed a central retinal artery occlusion (CRAO) with pale, white retinal swelling and a macular cherry-red spot. Fundus fluorescein angiography showed delayed arterial filling with persistently reduced macular perfusion. CRAO was diagnosed in an otherwise healthy young male. Systemic workup was negative except for protein electrophoresis, which showed sickle cell trait, and HbA1C was 7.8%. Later, atrophic macular changes with a pale optic disc were observed, and BCVA was reduced to light perception. CRAO in young patients amounts to diverse causes, which require extensive systemic workup. In addition, the concurrence of the sickle cell trait with diabetes mellitus might have a role in CRAO development.

Interventions for acute non-arteritic central retinal artery occlusion

BACKGROUND

Acute non-arteritic central retinal artery occlusion (CRAO) occurs as a sudden interruption of the blood supply to the retina and typically results in severe loss of vision in the affected eye. Although many therapeutic interventions have been proposed, there is no generally agreed upon treatment regimen.

OBJECTIVES

To assess the effects of treatments for acute non-arteritic CRAO.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2022, Issue 2); Ovid MEDLINE; Embase.com; PubMed; Latin American and Caribbean Health Sciences Literature Database (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 15 February 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing any interventions with another treatment in participants with acute non-arteritic CRAO in one or both eyes.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology and graded the certainty of the body of evidence for primary (mean change in best-corrected visual acuity [BCVA]) and secondary (quality of life and adverse events) outcomes using the GRADE classification.

MAIN RESULTS

We included six RCTs with 223 total participants with acute non-arteritic CRAO; the studies ranged in size from 10 to 84 participants. The included studies varied geographically: one in Australia, one in Austria and Germany, two in China, one in Germany, and one in Italy. We were unable to conduct any meta-analyses due to study heterogeneity. None of the included studies compared the same pair of interventions: 1) tissue plasminogen activator (t-PA) versus intravenous saline; 2) t-PA versus isovolemic hemodilution, eyeball massage, intraocular pressure reduction, and anticoagulation; 3) nitroglycerin, methazolamide, mecobalamin tablets, vitamin B1 and B12 injections, puerarin and compound anisodine (also known as 654-2) along with oxygen inhalation, eyeball massage, tube expansion, and anticoagulation compared with and without intravenous recombinant tissue plasminogen activator (rt-PA); 4) transcorneal electrical stimulation (TES) with 0 mA versus with 66% of the participant's individual electrical phosphene threshold (EPT) at 20 Hz (66%) versus with 150% of the participant's individual EPT (150%) at 20 Hz; 5) ophthalmic artery branch retrograde thrombolysis versus superselective ophthalmic artery thrombolysis; and 6) pentoxifylline versus placebo. There was no evidence of an important difference in visual acuity between participants treated with t-PA versus intravenous saline (mean difference [MD] at 1 month -0.15 logMAR, 95% confidence interval [CI] -0.48 to 0.18; 1 study, 16 participants; low certainty evidence); t-PA versus isovolemic hemodilution, eyeball massage, intraocular pressure reduction, and anticoagulation (MD at 1 month -0.00 logMAR, 95% CI -0.24 to 0.23; 1 study, 82 participants; low certainty evidence); and TES with 0 mA versus TES with 66% of EPT at 20 Hz versus TES with 150% of EPT at 20 Hz. Participants treated with t-PA experienced higher rates of serious adverse effects. The other three comparisons did not report statistically significant differences. Other studies reported no data on secondary outcomes (quality of life or adverse events).  AUTHORS' CONCLUSIONS: The current research suggests that proposed interventions for acute non-arteritic CRAO may not be better than observation or treatments of any kind such as eyeball massage, oxygen inhalation, tube expansion, and anticoagulation, but the evidence is uncertain. Large, well-designed RCTs are necessary to determine the most effective treatment for acute non-arteritic CRAO.

Central Retinal Artery Occlusion: Time to Presentation and Diagnosis

OBJECTIVE

To evaluate the presentation patterns of patients diagnosed with central retinal artery occlusion (CRAO) from 2011 to 2020.

DESIGN

Retrospective cohort study SUBJECTS: The present study was conducted in 484 patients presenting within 30 days of symptom onset with accurate documentation of time of symptom onset, time of presentation to the health care system, and time of presentation to an ophthalmologist.

METHODS

An independent chart review of patients with CRAO was conducted.

MAIN OUTCOME MEASURES

Demographic information including age, sex, and race were collected. Presentation patterns such as time of first symptoms, time of first contact with the health care system, and time of evaluation by an ophthalmologist were analyzed. Additionally, information regarding the medical venue or specialty of initial patient contact was collected.

RESULTS

A total of 247 (51%) patients contacted the health care system within 4.5 hours of system onset, whereas 86 (17.8%) patients waited over 24 hours. Only 81 (32.8%) of the 247 patients who presented within 4.5 hours saw an ophthalmologist within that time frame, whereas 172 (35.5%) of the entire cohort of 484 did not present to an ophthalmologist within 24 hours of vision loss. There was significant variability with regards to medical specialty of initial patient contact, with 292 (60.3%) patients first presenting to an emergency department and 133 (27.5%) patients first presenting to an ophthalmologist. Black and Hispanic patients presented later than patients of White, Asian, or other racial backgrounds (40.4 ± 10.2 hours versus 23.0 ± 3.4 hours, P = 0.05).

CONCLUSIONS

Although no level 1 evidence-based treatment is currently available for CRAO, thrombolytic therapy may be promising. Even though over half of patients with CRAO within our institution connected with the health care system within a potential window for thrombolytic therapy, most did not receive a definitive ophthalmic diagnosis within that time frame. Public health educational campaigns and infrastructure optimization must speed up presentation times, decrease the time to ophthalmic diagnosis, and target vulnerable populations to offer and research timely administration of thrombolytic therapy.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.

Efficacy and safety of intra-arterial thrombolysis in patients with central retinal artery occlusion: a systematic review and meta-analysis

PURPOSE

To investigate the efficacy and safety of intra-arterial thrombolysis (IAT) in patients with central retinal artery occlusion (CRAO).

METHODS

PubMed and EMBASE were searched for potentially eligible studies that reported IAT in CRAO patients from inception to Nov 8, 2021. Standard mean difference (SMD) was pooled to compare visual acuity (VA) at baseline with final in IAT patients. The rates and odds ratios (OR) were meta-analyzed to compare VA improvement in IAT with non-IAT patients, stratified to different times from onset to procedure, different definitions of VA improvement, and three CRAO stages. Adverse effects were recorded.

RESULTS

Fifteen studies were included, enrolling 507 CRAO patients who received IAT and 296 CRAO patients who did not. VA was significantly improved from baseline to final VA in IAT patients (SMD [LogMAR] 0.70, 95% CI [0.51, 0.90]). VA improvement rate was higher in IAT patients than that in non-IAT (56% vs 32%, OR 3.55, 95%CI [1.74, 7.24]), with greater OR in IAT within 6 h from onset to procedure (OR 4.60, 95%CI [1.24, 16.99]) than that beyond 6 h (OR 3.36, 95%CI [1.43, 7.85]). The benefit remained consistent when VA improvement was defined as ≥ 3 lines on the Snellen chart (OR 4.68, 95%CI [2.10, 10.41]) and was even greater when CRAO was incomplete. Five patients had a symptomatic intracranial hemorrhage and 21 patients had ischemic stroke or transient ischemic attack after IAT.

CONCLUSIONS

IAT treatment has certain potential in ameliorating VA in CRAO patients, which should be balanced against cerebral complications.

Point-of-care ultrasound in the detection of central retinal artery occlusion in a patient with recent COVID-19

Ocular emergencies are a frequent occurrence in the emergency setting. Fortunately, point-of-care ultrasound (POCUS) lends itself exceptionally well to ocular evaluation. Here, we present a unique case of central retinal artery occlusion rapidly diagnosed with POCUS in a patient with a recent COVID-19 diagnosis.

Perioperative Care of the Patient with Eye Pathologies Undergoing Nonocular Surgery

The authors reviewed perioperative ocular complications and implications of ocular diseases during nonocular surgeries. Exposure keratopathy, the most common perioperative eye injury, is preventable. Ischemic optic neuropathy, the leading cause of perioperative blindness, has well-defined risk factors. The incidence of ischemic optic neuropathy after spine fusion, but not cardiac surgery, has been decreasing. Central retinal artery occlusion during spine fusion surgery can be prevented by protecting eyes from compression. Perioperative acute angle closure glaucoma is a vision-threatening emergency that can be successfully treated by rapid reduction of elevated intraocular pressure. Differential diagnoses of visual dysfunction in the perioperative period and treatments are detailed. Although glaucoma is increasingly prevalent and often questions arise concerning perioperative anesthetic management, evidence-based recommendations to guide safe anesthesia care in patients with glaucoma are currently lacking. Patients with low vision present challenges to the anesthesia provider that are becoming more common as the population ages.

Risk Factors and Treatment Strategy for Retinal Vascular Occlusive Diseases

Retinal occlusive diseases are common diseases that can lead to visual impairment. Retinal artery occlusion and retinal vein occlusion are included in the clinical entity, but they have quite different pathophysiologies. Retinal artery occlusion is an emergent eye disorder. Retinal artery occlusion is mainly caused by thromboembolism, which frequently occurs in conjunction with life-threatening stroke and cardiovascular diseases. Therefore, prompt examinations and interventions for systemic vascular diseases are often necessary for these patients. Retinal vein occlusion is characterized by retinal hemorrhage and ischemia, which may impair visual function via several complications such as macular edema, macular ischemia, vitreous hemorrhage, and neovascular glaucoma. Even though anti-vascular endothelial growth factor therapy is the current established first-line of treatment for retinal vein occlusion, several clinical studies have been performed to identify better treatment protocols and new therapeutic options. In this review, we summarize the current findings and advances in knowledge regarding retinal occlusive diseases, particularly focusing on recent studies, in order to provide an update for a better understanding of its pathogenesis.

Changes in macrophage-like cells characterized by en face optical coherence tomography after retinal stroke

Purpose

The retina could serve as a window of neuroinflammation, but the in vivo changes in macrophage-like cell (MLC), such as microglia, in acute ischemic retinal stroke remain unclear. Thus, the current study aimed to investigate the in vivo changes in MLC characterized by en face optical coherence tomography (OCT) after acute ischemic retinal stroke.

Methods

Twenty patients with unilateral acute nonarteritic reperfused central retinal artery occlusion (CRAO) were participated in this study, and their contralateral eyes served as control group. A 3 μm en face OCT slab on the inner limiting membrane of the optic nerve head (ONH) region or macular region was used to visualize and binarize the MLCs. The MLCs were binarized and quantified using a semiautomated method. OCT angiography was used to evaluate the reperfusion status and obtain the structural data of the inner retina in the ONH and macula. The thickness of the ganglion cell complex in the macular region was measured. The optical intensity and optical intensity ratio of the inner retina were calculated to evaluate the ischemia severity.

Results

In the ONH region, decreased vessel densities of radial peripapillary capillaries accompanied by increased thickness of the retinal nerve fiber layer were found in the CRAO eyes in comparison to the unaffected eyes (p=0.001, p=0.009, respectively). In the macular region, significantly lower vessel densities in both the superficial and deep capillary plexus and increased thickness of the ganglion cell complex were also found in the CRAO eyes (all p ≤ 0.001). The ONH and macular MLC quantities and densities in CRAO eyes were significantly higher than those in the unaffected eyes (both p<0.001). Larger and plumper MLCs were observed in the CRAO eyes compared with their unaffected eyes. ONH and macular MLC densities were positively associated with the disease duration in the acute phase and the optical intensity ratio of inner retina.

Conclusions

The increased density and morphological changes of MLCs may indicate the aggregation and activation of MLCs following acute reperfused CRAO. The aggregation of MLCs may be more pronounced in CRAO eyes with longer disease duration and more severe ischemia. MLCs characterized by en face OCT may serve as an in vivo visual tool to investigate neuroinflammation in the ischemic-reperfusion process of stroke.

Retinal and optic nerve magnetic resonance diffusion-weighted imaging in acute non-arteritic central retinal artery occlusion

OBJECTIVES

Diffusion weighted imaging hyperintensity (DWI-H) has been described in the retina and optic nerve during acute central retinal artery occlusion (CRAO). We aimed to determine whether DWI-H can be accurately identified on standard brain magnetic resonance imaging (MRI) in non-arteritic CRAO patients at two tertiary academic centers.

MATERIALS AND METHODS

Retrospective cross-sectional study that included all consecutive adult patients with confirmed acute non-arteritic CRAO and brain MRI performed within 14 days of CRAO. At each center, two neuroradiologists masked to patient clinical data reviewed each MRI for DWI-H in the retina and optic nerve, first independently then together. Statistical analysis for inter-rater reliability and correlation with clinical data was performed.

RESULTS

We included 204 patients [mean age 67.9±14.6 years; 47.5% females; median time from CRAO to MRI 1 day (IQR 1-4.3); 1.5 T in 127/204 (62.3%) and 3.0 T in 77/204 (37.7%)]. Inter-rater reliability varied between centers (κ = 0.27 vs. κ = 0.65) and was better for retinal DWI-H. Miss and error rates significantly differed between neuroradiologists at each center. After consensus review, DWI-H was identified in 87/204 (42.6%) patients [miss rate 117/204 (57.4%) and error rate 11/87 (12.6%)]. Significantly more patients without DWI-H had good visual acuity at follow-up (p = 0.038).

CONCLUSIONS

In this real-world case series, differences in agreement and interpretation accuracy among neuroradiologists limited the role of DWI-H in diagnosing acute CRAO on standard MRI. DWI-H was identified in 42.6% of patients and was more accurately detected in the retina than in the optic nerve. Further studies are needed with standardized novel MRI protocols.

Retinal Infarction: A Pilot Study on the Efficacy and Safety of Intravenous Thrombolysis and Underlying Aetiologies

Background: Treatment of non-arteritic central retinal artery occlusion is still inconsistent. Therefore, the current study aimed to evaluate the efficacy of intravenous thrombolysis (IVT) and describe the prevalence of co-occurring ischemic brain lesions in patients with acute visual loss due to ischemia. Methods: We analysed 38 consecutive patients with acute visual loss between January 2015 and June 2020. Patients presenting within 4.5 h of symptom onset without any contraindication were treated with IVT. Patients underwent neurologic and ophthalmologic examination and diagnostic workup for the underlying aetiology. Follow-up was performed after 3 and 12 months. Results: Patients treated with IVT had a significantly better functional outcome at discharge compared to patients treated conservatively. No additional ischemic brain lesions were detected (0 of 38). Three patients had extracranial carotid artery stenosis ≥50%. Atrial fibrillation was present in four patients, three of whom already received oral anticoagulation. In the remaining 31 patients no embolic source was detected. However, the number of plaques were rated mild to moderate. Within three months, one patient developed transient visual loss while another suffered a contralateral transient ischemic attack. Conclusions: IVT may represent a safe and effective treatment option in patients with isolated visual loss due to ischemia. The aetiology was atherosclerotic burden rather than embolism caused by carotid stenosis or atrial fibrillation, bringing the current diagnostic procedure and therapy into question. Randomized trials are necessary to evaluate the efficacy and safety of IV thrombolysis and clarify the aetiology of isolated visual loss due to ischemia.

Light color efficiency-balanced trans-palpebral illumination for widefield fundus photography of the retina and choroid

A wide-field fundus camera, which can selectively evaluate the retina and choroid, is desirable for better detection and treatment evaluation of eye diseases. Trans-palpebral illumination has been demonstrated for wide-field fundus photography, but its application for true-color retinal imaging is challenging due to the light efficiency delivered through the eyelid and sclera is highly wavelength dependent. This study is to test the feasibility of true-color retinal imaging using efficiency-balanced visible light illumination, and to validate multiple spectral imaging (MSI) of the retina and choroid. 530 nm, 625 nm, 780 nm and 970 nm light emission diodes (LED)s are used to quantitatively evaluate the spectral efficiency of the trans-palpebral illumination. In comparison with 530 nm illumination, the 625 nm, 780 nm and 970 nm light efficiencies are 30.25, 523.05, and 1238.35 times higher. The light efficiency-balanced 530 nm and 625 nm illumination control can be used to produce true-color retinal image with contrast enhancement. The 780 nm light image enhances the visibility of choroidal vasculature, and the 970 nm image is predominated by large veins in the choroid. Without the need of pharmacological pupillary dilation, a 140° eye-angle field of view (FOV) is demonstrated in a snapshot fundus image. In coordination with a fixation target, the FOV can be readily expanded over the equator of the eye to visualize vortex ampullas.

Current diagnosis and treatment practice of central retinal artery occlusion: results from a survey among German stroke units

BACKGROUND

Central retinal artery occlusion (CRAO) is a neuro-ophthalmological emergency whose optimal management is still under debate and due to the absence of definite guidelines, practice is expected to vary. We aimed to characterize early evaluation as well as acute treatment and diagnostic approaches in German hospitals with a stroke unit (SU).

METHODS

In 07/2021, all 335 certified German SUs were invited to participate in an anonymous online survey endorsed by the German Stroke Society on emergency department care organization, diagnostic procedures, and treatment of patients with unilateral vision loss (UVL) subsequently diagnosed with CRAO.

RESULTS

One hundred and sixty-three (48.6%) of the 335 eligible centers responded. Most (117/135; 86.7%) stated that UVL patients were treated as an emergency, in 62/138 (44.9%) hospitals according to specific guidelines. First-line evaluation was performed by neurologists in 85/136 (62.5%) hospitals, by ophthalmologists in 43/136 (31.6%) hospitals. Seventy of 135 (51.9%) respondents indicated a lack of on-site ophthalmological expertise. Seventy-four of 129 (57.4%) respondents performed thrombolysis in CRAO and 92/97 (94.8%) stated that patients with CRAO-if admitted to neurology-were treated on a SU.

CONCLUSIONS

Our findings reflect notable heterogeneity in early intrahospital care of CRAO in German SUs but demonstrate a preference for work-up and management as acute stroke by the involved neurologists. Streamlining interdisciplinary emergency evaluation is essential for ongoing and future prospective trials.