A review of central retinal artery occlusion: clinical presentation and management

Prognostic factors for acute central retinal artery occlusion treated with hyperbaric oxygen: The Hong Kong study report number five

BACKGROUND

Central retinal artery occlusion (CRAO) is a potentially blinding disease, and hyperbaric oxygen therapy (HBOT) is becoming increasingly popular with the support of scientific evidence. Despite the presence of various acute management measures, there is no clear evidence on the gold standard treatment for CRAO.

AIM

To identify factors and imaging parameters associated with good visual outcome, which guide ophthalmologists in the triage of CRAO patients for HBOT.

METHODS

Patients who suffered from CRAO and had a symptom onset ≤ 6 h were recruited for a course of HBOT in a tertiary hospital after failing bedside treatment. Patient demographics, onset time, CRAO eye parameters, and past medical history were prospectively collected. Visual outcomes after HBOT were also analyzed.

RESULTS

A total of 26 patients were included; the female-to-male ratio was 1:1.6, and the mean age was 67.5 years ± 13.3 years (range 44–89 years). The mean duration of follow-up and mean visual acuity (VA) improvement were 10.0 mo ± 5.3 mo and 0.48 logarithm of minimal angle of resolution (logMAR) ± 0.57 logMAR (approximately 9 letters in ETDRS) (P = 0.0001, Z = -3.67), respectively. The 1 mm zone of central macular thickness (CMT) on optical coherence tomography was not associated with VA changes (P = 0.119); however, the 1-to-3 mm circular rim of CMT was fairly associated (P = 0.02, Spearman's coefficient = 0.45). Complete retinal perfusion time during fundus fluorescein angiography (FFA) was moderately associated (P = 0.01, Spearman's coefficient = 0.58) with visual outcome.

CONCLUSION

A thinner 1-to-3 mm circular rim of CMT, but not the central 1 mm zone, is associated with better visual outcome. A shorter perfusion delay on FFA is also associated with better visual outcome.

Hyperbaric Oxygen Therapy: An Evidence-Based Primer for Emergency Physicians

BACKGROUND

Hyperbaric medicine is a subspecialty that many emergency physicians may not encounter frequently in their daily practice. As such, we hope to provide a review, where we present an overview of hyperbaric oxygen therapy, complications from the therapy, and a description of how the treatments are administered. We also discuss seven emergency indications that may benefit from transfer to a hyperbaric facility for treatment.

OBJECTIVE OF THE REVIEW

Our aim is to provide an overview of hyperbaric oxygen therapy as it pertains to an emergency physician. We hope that this review will help emergency physicians identify conditions that may benefit from transfer to a hyperbaric facility.

DISCUSSION

We discuss seven emergency conditions that may benefit from transfer to a hyperbaric facility for management-decompression sickness, arterial gas embolism, central retinal artery occlusion, carbon monoxide poisoning, crush injury, necrotizing soft tissue infection, and symptomatic anemia. We also describe special considerations for how to transfer patients needing evaluation by a hyperbaric physician.

CONCLUSIONS

This review aims to describe hyperbaric oxygen therapy, identify conditions that may benefit from treatment with hyperbaric oxygen, and discuss management of patients with those conditions as it pertains to an emergency physician.

Visual outcomes of central retinal artery occlusion: Exploring treatment strategies beyond the conventional time window

BACKGROUNDS/AIMS

Central retinal artery occlusion (CRAO) is a vision-devastating emergency. However, widely-acknowledged treatment consensus is lacking and prehospital delays commonly occur. Hence, we aimed to investigate the visual outcomes of conservative treatments (CT), local intra-arterial fibrinolysis (LIF) and hyperbaric oxygen (HBO) therapy for non-arteritic CRAO (NA-CRAO) patients beyond the conventional time window.

METHODS

This retrospective comparative study included 99 NA-CRAO patients followed up for over 6 months. The subjects were divided into three groups: the CT (50 patients), LIF (10 patients) and HBO group (39 patients). The primary endpoint was the best-corrected visual acuity (BCVA) change at 6 months compared to baseline. The secondary endpoint was the improvement in BCVA at 1 year and final visits.

RESULTS

No heterogeneity regarding demographics was identified. However, the HBO group had a more extended time-to-treatment period (median 6.0 days) and more advanced-stage CRAO cases (41 % stage III) than the CT (median 4.0 days, 14 % stage III) and LIF (median 0.6 days, 20 % stage III) groups. Despite this, the HBO group exhibited a significantly greater BCVA and a higher proportion of patients achieving significant vision improvement than those in the CT group at 6-, 12-month and final exams (51.3 % vs. 24.0 %, P < 0.05). The LIF appeared to improve outcomes more than CT over time without significance.

CONCLUSION

Our study provided a concurrent comparison across 3 approaches and demonstrated that HBO therapy beyond the time window remained more effective in improving vision than CT alone for NA-CRAO patients, which had not been proposed by prior studies.

Ophthalmic artery branches and adjacent nerves observed on sectioned images of cadaver

The ophthalmic artery plays a vital role in supplying the eyeball and neighboring structures, and is associated with various clinical conditions. In this study, high-resolution cadaver-sectioned images were used to provide an intricate morphology of the ophthalmic artery and its branches, along with the oculomotor, trochlear, ophthalmic, and abducens nerves. This study presents a combination of schematics and cadaver-sectioned images, allowing for a clear representation of intricate anatomic structures. This study elucidated the spatial relationships among the ophthalmic artery, cranial nerves, and adjacent anatomic features. The branches of the ophthalmic artery were classified into three categories. The complex anatomy of the ophthalmic artery and adjacent nerves was examined on cadaver-sectioned images and is schematically illustrated. The utilization of cadaver-sectioned images presents advantages over traditional dissection techniques. This approach maintains the original positioning of the ophthalmic artery and nerves, enhancing accuracy. This study enriches the comprehension of ophthalmic anatomy, offers a helpful resource for interpreting clinical images, and facilitates various medical procedures. As a result, we anticipate that our research will contribute to advancing the diagnosis and management of eye disorders, offering fresh perspectives on the relationship between the ophthalmic artery and the surrounding structures.

The Neutrophil to Lymphocyte Ratio and Other Full Blood Count Indices in Retinal Diseases: A Systematic Review of the Literature

Background and Objectives: The neutrophil to lymphocyte ratio (NLR) and other full blood count indices have been used as a marker of inflammation in a variety of diseases. The aim of the current review is to summarize the existing knowledge on the use of these indices in retinal diseases. Materials and Methods: A systematic review of the literature was conducted to find eligible articles. The PUBMED and Scopus databases were systematically searched for relevant studies examining full blood count indices in retinal diseases. Results: The NLR was elevated in a number of vitreoretinal conditions, such as wet age-related macular degeneration (AMD), diabetic retinopathy and retinal vein occlusion, compared to controls. Full blood count indices could be useful in predicting the response to anti-VEG treatment in patients with wet AMD or diabetic macular edema (DME). Conclusions: The NLR and other indices can be used as diagnostic markers in retinal diseases and as prognostic factors of the response to treatment. The small sample size and short follow-up of the included studies and the variation in the measurement and cutoffs used for the NLR are limitations of its use in retinal conditions. Future studies need to further validate these findings and try to establish a link between these ratios and retinal phenotypes.

Cilioretinal artery occlusion after cataract and macular hole surgery: A case report

PURPOSE

To report cilioretinal artery occlusion in a patient undergoing cataract and macular hole surgery.

MATERIAL AND METHOD

A 78-year-old male patient was operated on for a left eye cataract and tractional macular hole. The patient had no intraoperative problems and developed sudden visual loss on the 15th postoperative day. Optic coherence tomography (OCT), fundus fluorescein angiography (FFA), and optic coherence tomography angiography (OCTA) images revealed occlusion of the cilioretinal artery. After medical treatment and 20 sessions of hyperbaric oxygen therapy, the best visual acuity was 50 cmFC, the optic nerve was pale, the macula was ischemic, and the central macular thickness was 139 microns at the last eye examination.

DISCUSSION

Mitigating the risk of cilioretinal artery occlusion after vitreoretinal surgery requires a comprehensive approach that addresses patient-specific factors, surgical techniques, and perioperative management.

CONCLUSION

Occlusion of the cilioretinal artery may rarely occur after cataract and macular hole surgery. Careful follow-up, early diagnosis, and prompt intervention can minimize visual loss.

Risk factors for endogenous endophthalmitis in infectious endocarditis patients

BACKGROUND/OBJECTIVES

The purpose of this study was to identify demographic variables and systemic comorbidities that may increase risk of endogenous endophthalmitis (EE) development in patients with infective endocarditis (IE).

SUBJECTS/METHODS

A retrospective database study was conducted using the 2002-2014 National Inpatient Sample (NIS). Patients with IE and EE were identified using ICD-9-CM codes. Descriptive chi-square and logistic regression analysis identified risk factors for EE in IE patients.

RESULTS

Of 769,472 inpatients with a diagnosis of IE, 2248 had a diagnosis of EE. Women comprised 39.7% of IE patients without EE and 42.6% of those with EE (p = 0.005). The majority of IE cases with EE were in those 21-64-year-old (58.5%) age cohort and 67.4% of cases were Whites. Multivariate analysis revealed IE patients in the 21-64 (OR, 3.660) and 65+ age group (OR, 2.852) had increased risk of developing EE compared to the 0-20-year-old group. Hispanic (OR, 1.377) and Asian/Pacific Islander (OR, 1.620) patients had increased risk compared to White patients. Diabetes with (OR, 2.043) and without (OR, 1.433) chronic complications, alcohol use disorder (AUD; OR, 1.795), and cirrhosis (OR, 1.452) conferred an increased risk of developing EE, whereas, congestive heart failure (CHF; OR, 0.716), arrhythmia (OR, 0.678), and having a cardiac device (OR, 0.336) decreased risk of EE in IE subjects.

CONCLUSION

Older age (21+ years) and Hispanic and Asian/Pacific Islander background were associated with increased risk of developing EE in IE patients. Diabetes with and without chronic complications, AUD, or cirrhosis also conferred a 1.5-2 times increased risk. CHF, arrhythmia, or having a cardiac device were associated with decreased risk.

Cataract Surgery and Incidence of Retinal Vascular Occlusion: Population-Based Cohort Study Using a Target Trial Emulation Framework

BACKGROUND

Previous studies suggested an association between cataract surgery and retinal vascular occlusion. However, the association may be attributable to detection bias because postoperative monitoring may be more frequent for those who receive cataract surgery than for those who do not.

DESIGN

Population-based cohort study using target trial emulation framework.

METHODS

We included patients with cataract aged 50 years and older receiving cataract surgery or nonsurgical interventions identified from the Taiwan National Health Insurance Research Database between 2003 and 2018, matched by propensity score. The primary outcome was retinal vascular occlusion. Cox proportional hazards models were used to compare surgery and control groups. Additional analyses were restricted to patients who had undergone fundoscopic examination within 6 months prior to cataract surgery to address the issue of detection bias.

RESULTS

We included 577,129 cataract surgery and control pairs. We found the hazard ratio (HR) for retinal vascular occlusion after cataract surgery was 1.23 (95% confidence interval (CI): 1.17-1.29), compared with the control group. Secondary outcome analyses yielded similar results for retinal artery occlusion (HR: 1.13, 95% CI: 1.02-1.26) and retinal vein occlusion (HR: 1.26, 95% CI: 1.20-1.33). However, no risk of retinal vascular occlusion was observed among patients who had received fundoscopic examinations (HR: 1.06, 95% CI: 0.98-1.15) at baseline.

CONCLUSIONS

Our study underscored the importance of conducting complete baseline fundoscopic examinations before cataract surgery to clarify whether postoperative conditions are due to patients' underlying diseases or unintended complications of cataract surgery.

Associations Between Retinal Vascular Occlusions and Dementia

BACKGROUND/OBJECTIVES

Retinal vascular occlusions, such as retinal vein occlusion (RVO) and retinal artery occlusion (RAO), are associated with cognitive impairment, including dementia. Our objective was to examine the odds of dementia among patients with retinal vascular occlusion.

METHODS

This cross-sectional study included 474 patients with retinal vascular occlusion and 948 patients without retinal vascular occlusion (comparison group). Patients in the comparison group were age- and sex-matched to those with vascular occlusion. Logistic regression was used to analyze the odds of all-cause dementia, vascular dementia, and Alzheimer's disease after adjusting for demographic, clinical, and ophthalmic covariates. Main outcome measures included the presence of all-cause dementia, vascular dementia, and Alzheimer's disease.

RESULTS

Patients with RVO (n = 413) had increased odds for all-cause dementia (odds ratio (OR) = 2.32; 95% confidence interval (CI): 1.44-3.75; p < 0.001) and vascular dementia (OR = 3.29; 95% CI: 1.41-7.68; p = 0.006) relative to the comparison group. Patients with central RVO (n = 192) (OR = 2.32; 95% CI: 1.19-4.54; p = 0.014) or branch RVO (n = 221) (OR = 2.68; 95% CI: 1.30-5.50; p = 0.007) had increased odds for all-cause dementia relative to the comparison group. Patients with RAO (n = 61) did not have increased odds of all-cause dementia (OR = 1.01; 95% CI: 0.32-3.26; p = 0.983), vascular dementia (OR = 1.54; 95% CI: 0.22-10.81; p = 0.663), or Alzheimer's disease (OR = 0.32; 95% CI: 0.05-2.20; p = 0.244).

CONCLUSIONS

A history of any RVO is associated with increased rates of all-cause dementia and vascular dementia independent of shared cardiovascular risk factors. These associations are not seen with a history of RAO, or between any subtype of vascular occlusions and Alzheimer's disease.

Ocular Ultrasound

Point-of-care ultrasound may be used to assist in the diagnosis of ocular complaints in the emergency department. With the use of a linear probe, the emergency physician can view anterior and posterior chamber structures of the patient's eye and evaluate for signs of pathology.

Position paper on retinal arterial occlusion. SEMI-SERV

The retina is an organ frequently affected by ischemic changes. Retinal arterial occlusion can be considered the equivalent of stroke, in terms of presentation, management and treatment. In addition to a specific ophthalmological treatment systemic management is essential with an appropriate study and control of cardiovascular risk factors considering these patients of a very high cardiovascular risk. In this consensus document we aim to provide an update on this relatively frequent pathology in our practices, considering the importance of an early and systematic action.

A unique complication of thyroidectomy for Hashimoto's thyroiditis: central retinal artery thrombosis

BACKGROUND

Central retinal artery occlusion (CRAO) is a rare ophthalmological emergency and also a unique complication after thyroid surgery.

METHODS

We present the first case of CRAO following thyroid surgery in a patient with Hashimoto's thyroiditis, along with a variety of interventions to overcome this complication.

RESULTS

A 42-year-old female patient suffering from sudden vision loss following total thyroidectomy was diagnosed with CRAO. Hyperbaric oxygen therapy was started within the postoperative first 6 hours.

CONCLUSION

Although it is extremely rare, it should be noted that patients may experience retinal artery occlusion following the thyroid surgery. Immediate evaluation of patients with visual impairment in the early postoperative period, and planning of emergent hyperbaric oxygen therapy for the management are critical.

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.

Prostanoid signaling in retinal vascular diseases

The vasculature of the retina is exposed to systemic and local factors that have the capacity to induce several retinal vascular diseases, each of which may lead to vision loss. Prostaglandin signaling has arisen as a potential therapeutic target for several of these diseases due to the diverse manners in which these lipid mediators may affect retinal blood vessel function. Previous reports and clinical practices have investigated cyclooxygenase (COX) inhibition by nonsteroidal anti-inflammatory drugs (NSAIDs) to address retinal diseases with varying degrees of success; however, targeting individual prostanoids or their distinct receptors affords more signaling specificity and poses strong potential for therapeutic development. This review offers a comprehensive view of prostanoid signaling involved in five key retinal vascular diseases: retinopathy of prematurity, diabetic retinopathy, age-related macular degeneration, retinal occlusive diseases, and uveitis. Mechanistic and clinical studies of these lipid mediators provide an outlook for therapeutic development with the potential to reduce vision loss in each of these conditions.

Visual acuity improvement after treatment of central retinal artery occlusion: a case report

Central Retinal Artery Occlusion (CRAO) is a serious ophthalmic emergency characterized by sudden, painless vision loss in one eye. This condition leads to rapid and significant visual impairment if not treated promptly. This case illustrates an adult man with hypertension presented with unilateral, painless, sudden vision loss occurring 13 hours before admission. Examination revealed a visual acuity of 1-meter counting finger in the affected eye, a cherry red spot, and a pale retina. Diagnosed with CRAO, immediate interventions included ocular massage, and acetazolamide loading alongside systemic antihypertensive medication. Visual acuity improved significantly, with the patient able to see 5/30 on the nasal side and can maintain this visual acuity until 6 months follow-up. Immediate and aggressive treatment for CRAO can lead to significant visual recovery even when initiated beyond the traditionally recommended time frame, underscoring the need for quick recognition and intervention in CRAO cases.

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.

Optometric Practice Patterns for Acute Central and Branch Retinal Artery Occlusion

BACKGROUND

Optometrists are often the first providers to evaluate patients with acute vision loss and are often the first to diagnose a central retinal artery occlusion (CRAO). How quickly these patients present to the optometrist, are diagnosed, and referred for evaluation are major factors influencing the possibility of acute therapeutic intervention. Our aim was to survey the U.S. optometric community to determine current optometric practice patterns for management of CRAO.

METHODS

An anonymous seven-question survey was emailed in 2020 to the 5,101 members of the American Academy of Optometry and the 26,502 members of the American Optometric Association.

RESULTS

Of 31,603 optometrists who were sent the survey, 1,926 responded (6.1%). Most respondents (1,392/1,919, 72.5%) worked in an optometry-predominant outpatient clinic and were less than 30 minutes from a certified stroke center (1,481/1,923, 77.0%). Ninety-eight percent (1,884/1,922) of respondents had diagnosed less than 5 CRAOs in the previous year, and 1,000/1,922 (52.0%) had not diagnosed a CRAO in the prior year. Of the optometrists who diagnosed at least one CRAO in the previous year, 661/922 (71.7%) evaluated these patients more than 4 hours after the onset of vision loss. Optometrists who diagnosed a CRAO or branch retinal artery occlusion referred patients to an emergency department (ED) affiliated with a certified stroke center (844/1,917, 44.0%), an outpatient ophthalmology clinic (764/1,917, 39.9%), an ED without a stroke center (250/1,917, 13.0%), an outpatient neurology clinic (20/1,917, 1.0%), or other (39/1,917, 2.0%); most (22/39, 56.4%) who responded "other" would refer to a primary care physician.

CONCLUSIONS

Optometrists are likely the first providers to evaluate patients with acute vision loss, including from a retinal artery occlusion. However, only 6.1% of optometrists responded to our survey despite 2 reminder emails, likely reflecting the lack of exposure to acute retinal artery occlusions, and a potential lack of interest of optometrists in participating in research. Of the optometrists who reported evaluating a CRAO in the previous year, less than 29% saw the patient within 4 hours of vision loss. In addition, a large portion of optometrists are referring acute CRAO patients to outpatient ophthalmology clinics, delaying appropriate acute management. Therefore, it is imperative that optometrists and ophthalmologists are educated to view acute retinal arterial ischemia as an acute stroke and urgently refer these patients to an ED affiliated with a stroke center. The delay in patient presentation and these referral patterns make future clinical trials for acute CRAO challenging.

Central retinal artery occlusion: a stroke of the eye

Central retinal artery occlusion (CRAO), like a stroke in the brain, is a critical eye condition that requiring urgent medical attention. Patients with CRAO present with acute loss of vision and the visual prognosis is poor with low chance of spontaneous visual recovery. Moreover, the risk of developing ischaemic heart disease and cerebral stroke is increased due to the presence of underlying atherosclerotic risk factors. Currently, there is no officially recommended treatment for CRAO. This review will describe the anatomy, pathophysiology, clinical features of CRAO, as well as exploring existing and potential future approaches for managing the condition.

Effects of Hyperbaric Oxygen Therapy in the Treatment of Patients With Central Retinal Artery Occlusion: A Retrospective Study

Background Central retinal artery occlusion (CRAO) results in sudden, painless vision loss. As an analogous condition to acute ischemic stroke, CRAO is an ophthalmological emergency, but a standardized treatment is lacking. Hyperbaric oxygen therapy (HBOT) has been widely used in spite of the inconsistent results reported. Purpose To report the visual acuity (VA) outcomes in all patients submitted to HBOT with non-arteritic CRAO in a tertiary center. Methods This retrospective study included all adult patients with CRAO and symptoms lasting for less than 24 hours who were prescribed HBOT in the Hyperbaric Medicine Unit of a Portuguese hospital from March 2009 to February 2023. Patient demographic information, medical history, ophthalmologic evaluation, hospital of referral, time until HBOT, supplementary treatments, number of HBOT sessions, adverse effects, and patient subjective VA gain were collected. All patients were subjected to 90-minute HBOT sessions with 100% oxygen at 2.4 ATA. The primary outcome was VA change (dif-logMAR) before and after treatment. A clinically significant visual improvement was defined as a dif-logMAR≥0.3. Data were analyzed using IBM SPSS Statistics for Windows, Version 29 (Released 2021; IBM Corp., Armonk, New York, United States) (p<0.05 is considered significant). Results A total of 114 patients were included in this study; 68% (n=77) were male, with a mean age of 69 years, and were subjected to a median number of seven HBOT sessions. No serious adverse effects from HBOT were reported. The mean time delay from symptoms to treatment was 12 hours, and best-corrected visual acuity (BCVA) at baseline was counting fingers or worse in 84% (n=96) of the patients. A dif-logMAR≥0.3 occurred in 46% (n=52) of the patients, and 58% (n=66) reported subjective VA improvement after the treatment. A significant improvement between BCVA before HBOT (2.12±0.74) and after HBOT (1.67±0.74) was observed. The VA outcome was found to be related to the total number of sessions, age, obesity, supplementary treatments, and cherry-red spot (CRS) at presentation. There were no significant effects of the time delay from symptoms to treatment in the explanation of the VA outcome. Conclusions HBOT appears to be safe and has a beneficial effect on VA outcomes in patients with non-arteritic CRAO, particularly depending on the number of sessions. Patient factors such as age, obesity, and the presence of CRSs also appear to influence the VA outcome.

AMALRIC TRIANGULAR SIGN AND CAROTID DOPPLER ULTRASONOGRAPHIC FINDINGS IN CENTRAL RETINAL ARTERY OCCLUSION

PURPOSE

The aim of this study was to determine the incidence of the Amalric triangular sign (ATS) in patients with central retinal artery occlusion and investigate its association with visual function and carotid Doppler ultrasonography findings.

METHODS

A retrospective chart review was conducted on 21 eyes from 21 patients with complete central retinal artery occlusion. Best-corrected visual acuity and carotid Doppler ultrasonography findings [peak systolic velocity, end-diastolic velocity, and resistance index (RI) = (PSV - EDV)/PSV] were investigated.

RESULTS

Three patients (14%) exhibited the ATS. Best-corrected visual acuity at first visit was significantly worse in ATS-positive patients than in ATS-negative patients (P = 0.024). Doppler waveform analysis of the common carotid artery showed that ATS-positive patients had a significantly lower end-diastolic velocity [P = 0.009, median 10 (range 9-10) vs. 17 (13-24) m/second] and significantly higher resistance index [P = 0.021, median 0.80 (range 0.79-0.83) vs. 0.72 (0.66-0.82)] than did ATS-negative.

CONCLUSION

The Amalric triangular sign was observed in three patients with central retinal artery occlusion, who showed worse best-corrected visual acuity at the first visit than did those without the ATS. Carotid Doppler ultrasonography revealed that ATS-positive patients had a significantly higher resistance index and lower end-diastolic velocity at the common carotid artery than did ATS-negative, indicating steno-occlusive changes in the internal carotid artery.

The Role of Optical Coherence Tomography Angiography in Glaucoma

Glaucoma is the leading cause of irreversible vision loss and comprises a group of chronic optic neuropathies characterized by progressive retinal ganglion cell (RGC) loss. Various etiologies, including impaired blood supply to the optic nerve, have been implicated for glaucoma pathogenesis. Optical coherence tomography angiography (OCTA) is a non-invasive imaging modality for visualizing the ophthalmic microvasculature. Using blood flow as an intrinsic contrast agent, it distinguishes blood vessels from the surrounding tissue. Vessel density (VD) is mainly used as a metric for quantifying the ophthalmic microvasculature. The key anatomic regions for OCTA in glaucoma are the optic nerve head area including the peripapillary region, and the macular region. Specifically, VD of the superficial peripapillary and superficial macular microvasculature is reduced in glaucoma patients compared to unaffected subjects, and VD correlates with functional deficits measured by visual field (VF). This renders OCTA similar in diagnostic capabilities compared to structural retinal nerve fiber layer (RNFL) thickness measurements, especially in early glaucoma. Furthermore, in cases where RNFL thickness measurements are limited due to artifact or floor effect, OCTA technology can be used to evaluate and monitor glaucoma, such as in eyes with high myopia and eyes with advanced glaucoma. However, the clinical utility of OCTA in glaucoma management is limited due to the prevalence of imaging artifacts. Overall, OCTA can play a complementary role in structural OCT imaging and VF testing to aid in the diagnosis and monitoring of glaucoma.

Increased risks of retinal vascular occlusion in patients with migraine and the protective effects of migraine treatment: a population-based retrospective cohort study

Associations between migraine and retinal vascular occlusion have been reported, but there is no large-scale and comprehensive study. Therefore, we aimed to determine risks of retinal vascular occlusion in patients with migraine. Using the Taiwan National Health Insurance Research Database from 2009 to 2020, we enrolled 628,760 patients with migraine and 628,760 matched individuals without migraine. Study outcomes were diagnoses of retinal vascular occlusion, including retinal artery occlusion (RAO) and retinal vein occlusion (RVO). Adjusted hazard ratio (aHR) of retinal vascular occlusion related to migraine was estimated. The cumulative incidences of subsequent retinal vascular occlusion, RAO, and RVO were significantly higher in migraine patients compared with controls (0.31% vs. 0.21%; 0.09% vs. 0.05%; 0.22% vs. 0.17%; all p < 0.001). The hazards of retinal vascular occlusion, RAO, and RVO were significantly greater in the migraine group (aHR, 1.69 [95% CI, 1.57, 1.83], 2.13 [95% CI, 1.84, 2.48] and 1.53 [95% CI, 1.40, 1.68], respectively). Risks of retinal vascular occlusion were significantly higher in migraine both with aura (MA) and without aura (MO) (aHR, 1.77 [95% CI, 1.58, 1.98], and 1.92 [95% CI, 1.64, 2.25]). Among patients with migraine, nonsteroidal anti-inflammatory drugs, propranolol, and flunarizine significantly reduce their risks of retinal vascular occlusion (aHR, 0.19 [95% CI, 0.16, 0.22], 0.73 [95% CI, 0.62, 0.86], 0.84 [95% CI, 0.76, 0.93]). Migraine, MA and MO are independently associated with higher risks of retinal vascular occlusion, RAO, and RVO.

Update on central retinal artery occlusion

The medical condition referred to as "central retinal artery occlusion" (CRAO) was first documented by Albrecht von Graefe in 1859. Subsequently, CRAO has consistently been identified as a serious medical condition that leads to substantial visual impairment. Furthermore, it is correlated with vascular complications that have the potential to affect crucial organs such as the brain and heart. A considerable amount of research has been extensively published on the various aspects of this topic, which is marked by notable debates and misconceptions, especially regarding its management and outcomes. The primary aim of this review article is to analyze the latest developments in the understanding of CRAO, which includes its causes, techniques for retinal imaging, systemic evaluation, and therapeutic strategies, such as vitrectomy. This review article offers readers a comprehensive learning experience to gain knowledge on the fundamental principles and recent advancements in CRAO.

Central Retinal Artery Occlusion Associated with Takayasu Arteritis

Takayasu arteritis is a chronic inflammatory vasculitis with granulomatous panarteritis particularly impacting large vessels including the aorta and its branches, especially the subclavian arteries, with clinical manifestation dependent on the involved artery. Sequelae of the active disease vary, including stenosis, occlusions, or aneurysmal dilatations of the large vessels. The prevalence of Takayasu arteritis is higher in the Asian population and in Japan, but quite low in the United States, varying from 0.9-8.4 per million people. Ocular manifestations are rare and lead to a delay in diagnosis and appropriate treatment. Ocular manifestations include Takayasu retinopathy, anterior ischemic optic neuropathy (AION), retinal artery occlusion (RAO) and retinal vein occlusion (RVO). We present two cases in which central retinal artery occlusion (CRAO) was associated with Takayasu arteritis. CRAO is an ophthalmic emergency with an incidence of 1.9 per 100,000 person years in the United States; only 5% of cases are arteritic, which can be observed with inflammatory vasculitides secondary to the formation of immune deposits.

Central Retinal Artery Occlusion: Visual Outcomes from a Large Northern California Cohort

PURPOSE

To assess visual acuity (VA) outcomes in a large cohort of patients diagnosed with nonarteritic central retinal artery occlusion (CRAO), and to ascertain whether time from symptom onset to presentation, presenting VA, or conservative treatment delivery (anterior chamber paracentesis, ocular massage, intraocular pressure lowering drugs, hyperventilation, or some combination of those) impacted ultimate VA outcomes.

DESIGN

Retrospective cohort study.

SUBJECTS

The study included 794 patients who presented with CRAO between 2011 and 2020. Within this cohort, 484 individuals presented within 30 days of symptom onset and had comprehensive documentation regarding the details of their presentation, management, and follow-up ≥ 90 days postdiagnosis.

METHODS

Retrospective chart review was conducted for all patients with a diagnosis of CRAO initially identified via International Classification of Diseases coding, followed by confirmation of diagnosis by 2 retina specialists. Cases of arteritic CRAO were excluded.

MAIN OUTCOME MEASURES

Visual acuity recovery, defined as improvement from ≤ 20/200 or worse at presentation to ≥ 20/100 ≥ 90 days after diagnosis.

RESULTS

Of the 794 identified patients, 712 (89.7%) presented with VA of ≤ 20/200. Similarly, 447 (92.4%) of the 484-patient subset that presented within 30 days and had comprehensive documentation presented with VA ≤ 20/200. Of the 441 of those patients with documented follow-up, 380 (86.2%) remained at that level. Of the 244 patients who presented within 4.5 hours of symptom onset, 227 (93%) presented ≤ 20/200 and 201 (92.6%) of the 217 of those with follow-up data did not improve beyond that threshold. There was no significant difference (P < 0.05) in final VA between patients presenting before versus after 4.5 hours from time of vision loss. There was also no significant difference (P < 0.05) in VA outcomes between patients who did or did not receive conservative treatment.

CONCLUSIONS

This large retrospective study further highlights the poor visual prognosis for patients with CRAO. Earlier time to presentation did not seem to impact final VA outcome, nor did conservative treatment efforts. Efficacious evidence-based treatment options are needed for this patient population.

FINANCIAL DISCLOSURE(S)

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

Implementation of a retinal stroke-code protocol results in visual recovery in patients receiving reperfusion therapies

INTRODUCTION

Reperfusion therapies represent promising treatments for patients with Central Retinal Artery Occlusion (CRAO), but access is limited due to low incidence and lack of protocols. We aimed to describe the benefit of implementing a Retinal Stroke-Code protocol regarding access to reperfusion, visual acuity and aetiological assessment.

PATIENTS AND METHODS

Prospective cohort study performed at a Comprehensive Stroke Centre. Criteria for activation were sudden monocular, painless vision loss within 6 h from onset. Eligible patients received IAT when immediately available and IVT otherwise. All patients were followed by ophthalmologists to assess best-corrected visual acuity (BCVA) and visual complications, and by neurologists for aetiological workup. Visual amelioration was defined as improvement of at least one Early Treatment Diabetic Retinopathy Study (ETDRS) letter from baseline to 1 week.

RESULTS

Of 49 patients with CRAO, 15 (30.6%) received reperfusion therapies (12 IVT, 3 IAT). Presentation beyond 6 h was the main contraindication. Patients receiving reperfusion therapies had better rates of visual improvement (33.3% vs 5.9%, p = 0.022). There were no complications related to reperfusion therapies. Rates of neovascular glaucoma were non-significantly lower in patients receiving reperfusion therapies (13.3% vs 20.6%, p = 0.701). Similar rates of atherosclerotic, cardioembolic and undetermined aetiologies were observed, leading to 10 new diagnosed atrial fibrillation and five carotid revascularizations.

CONCLUSION

A comprehensive acute management of CRAO is feasible despite low incidence. In our study, reperfusion therapies were safe and associated with higher rates of visual recovery. A similar etiological workup than ischemic stroke led to of high proportion of underlying aetiologies.

Thrombolysis in acute retinal ischemia treated with tenecteplase

Central retinal artery occlusion (CRAO), a type of acute retinal arterial ischemia, analogous to an ocular stroke, is a medical emergency that warrants immediate diagnosis and treatment. CRAO usually presents with sudden, painless, monocular vision loss. Ipsilateral carotid artery disease is an important associated finding in these patients. The primary limitation to effective treatment of CRAO is that patients are rarely seen in the acute stage. Moreover, there are no guidelines for effective treatment. We report a patient with right CRAO whose treatment with intravenous thrombolysis with tenecteplase and anterior chamber paracentesis with ocular massage resulted in a good clinical outcome.

Evaluation of Increase in Retinal Thickness as Diagnostic Marker in Central Artery Occlusion

PURPOSE

To evaluate the increase in retinal thickness as a marker in predicting the onset of central retinal artery occlusions.

METHODS

Retrospective clinical study conducted at one Swiss hospital. Electronic records were filtered for patients with artery occlusions. Optical coherence tomography data, including time between the imaging and ischemic event, were reviewed. Increase in relative retinal thickness was measured, defined as an increase in retinal thickness compared to the unaffected partner eye. This was correlated with the time from symptom onset. A cutoff value of relative increase of < 24.5% was applied, as suggested in previous studies. The results were compared to the time gathered from the electronic records, and sensitivity, specificity, positive predictive value as well as negative predictive value were calculated for predicting an ischemia time of < 4.5 h.

RESULTS

Forty-two eyes from 41 patients with central artery occlusions were identified. Fourteen were female. Mean age was 66.4 ± 15.8 years. Initial corrected visual acuity was 2.41 ± 0.68 logMAR, and 2.13 ± 0.87 logMAR at the last follow-up (p > 0.05). Of eyes with a visual acuity of counting fingers (n = 38) or worse, 89.5% showed no improvement during follow-up, while eyes with logMAR 1 or better (n = 4) improved. Thirteen eyes (13 patients) presented within 4.5 h of the ischemic event. Four patients received i. v. thrombolysis, with visual recovery in one. In 12 eyes with an ischemia time of < 4.5 h, relative increase was below 24.5%. In the remaining 29 eyes with > 4.5 h, relative increase was below 24.5% in 4 eyes and above 24.5% in 25 eyes. This yielded a sensitivity of 92.3%, a specificity of 86.2%, with a positive predictive value of 75.0% and a negative predictive value of 96.2%.

CONCLUSION

Central retinal artery occlusion is associated with severe vision loss. There is no current established therapy. Parameters that objectify the presence of a therapeutic window for thrombolysis are gaining in importance as patient history is often imprecise. Relative retinal thickness increase proved a noninvasive imaging parameter demonstrating adequate performance in detecting patients within the therapeutic window of thrombolysis. Further investigation of this parameter in central retinal occlusion is warranted.

Aetiology, Diagnosis and Treatment of Arterial Occlusions of the Retina-A Narrative Review

Arterial occlusions of the retina are potentially sight-threatening diseases which often result in profound visual loss. The aim of this narrative review is to provide an overview of the aetiology, discuss major risk factors, describe the management and systemic assessments and evaluate existing therapies. For this review, an extensive literature search in PubMed was performed. Emboli from the heart or the carotid arteries can cause ophthalmic artery occlusion (OAO), central retinal artery occlusion (CRAO) and branch retinal artery occlusion (BRAO). Most patients with arterial occlusions have vascular risk factors such as arterial hypertension, hyperhomocysteinaemia, carotid stenosis and atrial fibrillation, which also increase the risk of cerebral stroke and myocardial infarction. Therapies such as ocular massage, thrombolysis and anterior chamber paracentesis have been suggested but are still equivocal. However, it is evident that retinal artery occlusion should be immediately treated and accompanied by interdisciplinary collaboration, since early diagnosis and the proper treatment of possible risk factors are important to reduce the risk of further damage, recurrences, other vascular diseases and mortality.

Prevalence and Distribution of Macular Fluid with Central Retinal Artery Occlusion and Anterior Ischemic Optic Neuropathy

Purpose

To examine the prevalence and distribution of fluid within a cohort of eyes with acute central retinal artery occlusion (CRAO) and non-arteritic anterior ischemic optic neuropathy (AION) using optical coherence tomography (OCT).

Methods

A retrospective analysis of patient records and OCT imaging. Patients presenting with acute CRAO or AION who had available macular OCT imaging and no co-morbidities known to cause macular fluid were included in the analysis. Baseline characteristics, visual acuity (VA), and fluid presence and distribution among the retinal layers were recorded.

Results

In the 16 eyes with acute CRAO, fluid was noted in 5 eyes (31%), which was mainly subretinal (3 eyes) or intraretinal located within the outer retinal layers (3 eyes). Only one eye had inner retinal cysts. Of the 11 eyes with acute AION, fluid was present in 8 eyes (73%). Subretinal fluid was noted in 4 eyes and extended to the foveal area in 3 of them, and outer retinal versus inner retinal cysts were noted in 6 versus 3 eyes, respectively. None of the eyes showed hard exudate deposition. In the small subset of eyes with CRAO and macular fluid that were followed-up, VA improved, while in eyes with AION, VA remained stable.

Conclusion

Macular fluid on OCT is not an uncommon feature of acute CRAO and AION and is mainly distributed within the outer retinal layers or subretinal space. Fluid is an understudied feature of retinal and optic nerve head infarction and may have a role in predicting neuronal damage extent and visual outcome.

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.

BRANCH RETINAL ARTERY OCCLUSION IN A YOUNG PATIENT AFTER RADIOTHERAPY FOR NASOPHARYNGEAL CARCINOMA BRANCH RETINAL ARTERY OCCLUSION AFTER RADIOTHERAPY

PURPOSE

The aim of this study was to report a case of branch retinal artery occlusion in a young patient who received previous neck radiotherapy for nasopharyngeal carcinoma.

METHODS

The authors describe an interesting case of a branch retinal artery occlusion in a patient with previous neck radiotherapy for nasopharyngeal carcinoma 14 years ago. The patient was a 49-year-old man, who presented to the retina service in Tan Tock Seng Hospital.

RESULTS

Ultrasound of the carotid arteries revealed more than 50% bilateral common carotid arteries stenosis and 80-99% bilateral internal carotid artery stenosis. Magnetic resonance imaging of the brain showed presence of chronic infarcts. Screening for hypercoaguable states and cardioembolic causes were unremarkable.

CONCLUSION

Head and neck irradiation is a significant risk factor for developing carotid stenosis and its consequent complications such as retinal artery occlusions and cerebrovascular events.

Inhibition of retinal ischemia-reperfusion injury in rats by inhalation of low-concentration hydrogen gas

PURPOSE

To investigate the inhibitory effect of hydrogen gas inhalation on retinal ischemia reperfusion (I/R) injury using a rat model.

METHODS

Six-week-old male Sprague-Dawley rats were used. A 27G needle connected by a tube to a saline bottle placed 200 cm above the eye was inserted into the anterior eye chamber to create a rat retinal I/R model. In the ischemia-plus-hydrogen-gas group (H2( +) group), the ischemia time was set to 90 min, and 1.8% hydrogen was added to the air delivered by the anesthesia mask simultaneously with the start of ischemia. In the non-hydrogen-treatment ischemia group (H2( -) group), I/R injury was created similarly, but only air was inhaled. ERGs were measured; after removal of the eyes, the retina was examined for histological, immunostaining, and molecular biological analyses.

RESULTS

The mean thickness of the inner retinal layer in the H2( +) group was 107.2 ± 16.0 μm (n = 5), significantly greater than that in the H2( -) group (60.8 ± 6.7 μm). Immunostaining for Iba1 in the H2( -) group showed increased numbers of microglia and microglial infiltration into the subretinal space, while there was no increase in microglia in the H2( +) group. B-wave amplitudes in the H2( +) group were significantly higher than in the H2( -) group. In the membrane antibody array, levels of interleukin-6, monocyte chemotactic protein 1, and tumor necrosis factor alpha were significantly lower in the H2( +) group than in the H2( -) group.

CONCLUSION

Inhalation of 1.8% hydrogen gas inhibited the induction of inflammation, morphological/structural changes, and glial cell increase caused by retinal I/R injury.

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.

Perioperative Blindness in Spine Surgery: A Scoping Literature Review

Perioperative vision loss (POVL) is a devastating surgical complication that impacts both the recovery from surgery and quality of life, most commonly occurring after spine surgery. With rates of spine surgery dramatically increasing, the prevalence of POVL will increase proportionately. This scoping review aims to aggregate the literature pertinent to POVL in spine surgery and consolidate recommendations and preventative measures to reduce the risk of POVL. There are several causes of POVL, and the main contribution following spine surgery is ischemic optic neuropathy (ION). Vision loss often manifests immediately following surgery and is irreversible and severe. Diffusion weighted imaging has recently surfaced as a diagnostic tool to identify ION. There are no effective treatments; therefore, risk stratification for counseling and prevention are vital. Patients undergoing prone surgery of long duration and/or with significant expected blood loss are at greatest risk. Future research is necessary to develop effective treatments.

Efficacy of 2% Hydroxypropyl Methylcellulose and Bandage Contact Lens for the Management of Dry Eye Disease after Cataract Surgery

Objectives

To investigate the effect of 2% hydroxypropyl methylcellulose (HPMC) and bandage contact lens (BCL) on dry eye disease after cataract surgery.

Methods

This prospective randomized controlled trial included 63 eyes which were divided into the balanced salt solution (BSS), HPMC, BCL, and combined HPMC and BCL (H&B) groups. The Ocular Surface Disease Index (OSDI), tear meniscus height (TMH), and average tear break-up time were measured before cataract surgery and 30 days postoperatively. Differences in corneal nerve fiber (CNF) and dendritic cell (DC) density in various directions were evaluated and compared. The CNFs and DCs in central and infratemporal directions were observed using in vivo confocal microscopy. Data were evaluated using the Kruskal-Wallis rank-sum test and analysis of variance.

Results

The differences in variations in OSDI and TMH after cataract surgery between the four groups were statistically significant (P < 0.05). The postoperative OSDI of the HPMC group decreased compared with their preoperative OSDI. A statistically significant difference in the variations of OSDI score was observed between the HPMC and other groups (P < 0.05). The postoperative variations in TMH in the HPMC group were significantly higher than those observed preoperatively and significantly differed between HPMC and BCL groups and between BCL and H&B groups (P < 0.05). Postoperatively, the density of corneal DCs decreased in BSS and HPMC groups and increased in BCL and H&B groups (P < 0.001).

Conclusions

The application of 2% HPMC in cataract surgery has a certain effect on managing dry eye after cataract surgery. Although the use of BCLs after cataract surgery has some benefits, it may cause mild ocular surface inflammation. Nevertheless, using 2% HPMC with BCLs in the perioperative phase of cataract surgery can alleviate the subjective discomfort of patients and can safely and effectively replace eye patch after cataract surgery.

Network Meta-Analysis of Different Thrombolytic Strategies for the Treatment of Central Retinal Artery Occlusion

PURPOSE

Intravenous and intra-arterial thrombolytic strategies have been used to treat central retinal artery occlusion (CRAO); however, previous meta-analyses evaluated the efficacy of these two thrombolytic strategies separately but did not compare them. This network meta-analysis aimed to evaluate the comparative efficacy and safety of different thrombolytic methods for treating CRAO.

METHODS

We searched PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfangdata to identify relevant studies published before 1 January 2023. We used the "network" command in STATA 14.0 software to perform network meta-analysis. In addition, we calculated the surface under the cumulative ranking (SUCRA) to rank all currently available thrombolytic strategies.

RESULTS

We included 12 studies in the final data analysis. Results suggested that, compared with standard treatment (ST), intravenous tissue plasminogen activator (IVtPA) (OR, 5.78; 95% CI, 2.07 to 16.11) and intra-arterial urokinase (IAUK) (OR, 2.78; 95% CI, 1.10 to 7.02) and intra-arterial tPA (IAtPA) (OR, 2.45; 95% CI, 1.04 to 5.77) achieved better visual improvement. The differences in visual improvement among IVtPA, IAUK, and IAtPA are insignificant. Furthermore, compared with ST, administration of IVtPA within 4.5 hours of CRAO onset (OR, 8.87; 95% CI, 3.35 to 23.48) rather than administration after 4.5 hours of onset (OR, 3.09; 95% CI, 0.81 to 11.70) achieved better visual improvement. In addition, compared to ST, all available thrombolytic strategies we evaluated were associated with a higher risk of adverse events, but these strategies did not differ. Based on the results of SUCRA, IVtPA had the highest ranking probability in visual improvement (91.9%) but had a relatively lower ranking probability of adverse events (60.1%).

CONCLUSION

Both intravenous and intra-arterial thrombolytic strategies are effective for treating CRAO, but SUCRA results show that IVtPA may be the optimal strategy for treating CRAO. Furthermore, based on the results of subgroup analysis, we further speculate that IVtPA injection within 4.5 hours of the onset of CRAO should be the optimal thrombolytic option for treating CRAO. However, due to the limitations of all eligible studies, more studies are still required in the future to validate our findings.

Combined Central Retinal Artery Occlusion (CRAO) and Central Retinal Vein Occlusion (CRVO) in a Celiac Disease Patient: A Case Report

Celiac disease (CD) is a digestive disorder caused by an abnormal immune reaction to gluten, leading to severe malabsorption syndrome. Central retinal vein occlusion (CRVO) was reported in a couple of cases worldwide in patients with this disease entity. Herein, we are reporting a rare case of combined central retinal vein and artery occlusion in a young female celiac disease patient presented with a counting finger vision at six feet and improved to 20/60 vision after conservative management.

Incidence of Total Blindness After Central Retinal Artery Occlusion With Ocular Neovascularization

Purpose: To determine the time-based incidence of total blindness after central retinal artery occlusion (CRAO) with secondary ocular neovascularization (ONV). Methods: In this retrospective cohort study, electronic records were queried using ICD-9 and ICD-10 codes to identify patients with secondary ONV post-CRAO. Patients with possible alternative ONV etiologies, previous panretinal photocoagulation (PRP), and/or previous antivascular endothelial growth factor (anti-VEGF) therapy were excluded. Clinical data included demographics, medical comorbidities, ONV manifestations, medical/surgical management, and best-corrected visual acuity (BCVA). Kaplan-Meier analysis was performed with total blindness (defined as a BCVA of no light perception) as the outcome of interest. Results: Of 345 eyes with CRAO, 34 met the inclusion criteria with a mean (±SD) follow-up of 22.0 ± 26.2 months. ONV management included PRP (70.6%), glaucoma drainage implant surgery or transscleral cyclophotocoagulation (32.4%), and intravitreal anti-VEGF therapy (mean 2.8 ± 5.6 injections per patient). The cumulative incidence of total blindness was 49.4% (95% confidence interval, 27.2%-71.6%) at 24 months, with 53.3% of cases occurring within 4 months of ONV onset. Conclusions: Post-CRAO ONV is associated with a high risk for progression from severe vision loss to total blindness. Neovascular glaucoma can present up to 4 months after CRAO, challenging the paradigm of "30-day-glaucoma." Routine gonioscopy should extend through this period, while glaucoma surgery can delay further vision loss. These findings can be used to counsel patients on the importance of follow-up adherence.

Oxidative stress in the eye and its role in the pathophysiology of ocular diseases

Oxidative stress occurs through an imbalance between the generation of reactive oxygen species (ROS) and the antioxidant defense mechanisms of cells. The eye is particularly exposed to oxidative stress because of its permanent exposure to light and due to several structures having high metabolic activities. The anterior part of the eye is highly exposed to ultraviolet (UV) radiation and possesses a complex antioxidant defense system to protect the retina from UV radiation. The posterior part of the eye exhibits high metabolic rates and oxygen consumption leading subsequently to a high production rate of ROS. Furthermore, inflammation, aging, genetic factors, and environmental pollution, are all elements promoting ROS generation and impairing antioxidant defense mechanisms and thereby representing risk factors leading to oxidative stress. An abnormal redox status was shown to be involved in the pathophysiology of various ocular diseases in the anterior and posterior segment of the eye. In this review, we aim to summarize the mechanisms of oxidative stress in ocular diseases to provide an updated understanding on the pathogenesis of common diseases affecting the ocular surface, the lens, the retina, and the optic nerve. Moreover, we discuss potential therapeutic approaches aimed at reducing oxidative stress in this context.

Spontaneous Late Visual Recovery in Pediatric Central Retinal Artery Occlusion: A Case Report and Literature Review

The authors report a rare case of pediatric central retinal artery occlusion (CRAO) and spontaneous late recovery, with associated literature review. A retrospective review of patient medical records and literature search of four relevant databases was conducted. A 7-year-old girl with sudden, painless loss of vision in her right eye was referred to the authors' center where she was found to have a CRAO with hand motion visual acuity. One month later, the patient developed multiple retinal hemorrhages throughout the fundus. Despite undergoing extensive investigations, a cause for her condition was not determined. Seventeen months after the original event, the patient regained a visual acuity of 20/40. A CRAO in the pediatric population is relatively rare and requires extensive investigation into the potential cause. Compared to adult CRAO, presentation in the pediatric age group should warrant a high index of suspicion and extensive work-up to treat any underlying systemic conditions and possibly prevent involvement of the other eye. [J Pediatr Ophthalmol Strabismus. 2023;60(6):e70-e74.].

Central Retinal Artery Occlusion With Triple Cilioretinal Artery Sparing

We report a rare case of central retinal artery occlusion (CRAO) with triple cilioretinal artery sparing in a 76-year-old male with hypertension who presented with sudden diminution of vision in the left eye (OS) for one day. Optical coherence tomography angiography (OCTA) demonstrated the presence of three cilioretinal arteries and the absence of flow signals in the rest of the macula. Primary ophthalmic treatment was instituted immediately in the form of ocular massage, and acetazolamide 500 mg per oral (PO) stat was given. Systemic investigations revealed a significant blockage in coronary circulation on coronary angiography and an atheromatous plaque at the origin of the left internal carotid artery with 50% stenosis on digital subtraction angiography. Systemic anticoagulants and lipid-lowering agents (statins) were initiated by the cardiologist. Percutaneous transluminal coronary angioplasty was subsequently performed. At the eight-week follow-up visit, best-corrected visual acuity had improved to 2/60 OS. Fundus examination of the OS revealed optic disc pallor with normal retinal background. Spectral-domain optical coherence tomography showed diffuse retinal thinning except in the area supplied by the three patent cilioretinal arteries. En face OCTA OS showed restoration of retinal flow signal in the macula. Non-invasive imaging (OCTA) is critical in establishing early diagnosis and initiating prompt treatment in this ocular emergency with underlying potentially life-threatening systemic associations.

Retinal Findings and Cardiovascular Risk: Prognostic Conditions, Novel Biomarkers, and Emerging Image Analysis Techniques

Many retinal diseases and imaging findings have pathophysiologic underpinnings in the function of the cardiovascular system. Myriad retinal conditions, new imaging biomarkers, and novel image analysis techniques have been investigated for their association with future cardiovascular risk or utility in cardiovascular risk prognostication. An intensive literature search was performed to identify relevant articles indexed in PubMed, Scopus, and Google Scholar for a targeted narrative review. This review investigates the literature on specific retinal disease states, such as retinal arterial and venous occlusions and cotton wool spots, that portend significantly increased risk of future cardiovascular events, such as stroke or myocardial infarction, and the implications for personalized patient counseling. Furthermore, conditions diagnosed primarily through retinal bioimaging, such as paracentral acute middle maculopathy and the newly discovered entity known as a retinal ischemic perivascular lesion, may be associated with future incident cardiovascular morbidity and are also discussed. As ever-more-sophisticated imaging biomarkers and analysis techniques are developed, the review concludes with a focused analysis of optical coherence tomography and optical coherence tomography angiography biomarkers under investigation for potential value in prognostication and personalized therapy in cardiovascular disease.

Bilateral central retinal artery occlusion as a presenting manifestation of systemic lupus erythematosus: a case-based review

Central retinal artery occlusion (CRAO) is an ophthalmic emergency that typically results in permanent vision damage even despite vigorous treatment. In this article, we describe a case of acute vaso-occlusive retinopathy that presented as the primary manifestation of SLE in the absence of elevated levels of APLAs. After treatment with intravenous steroids, immunoglobulin, intrathecal injection of dexamethasone, plasma exchange, and intravenous cyclophosphamide, SLE was well controlled in the patient, but her vision was permanently lost in the left eye. We also go over a brief review of the currently available literature on retinal vaso-occlusive disease present in SLE. The pathology mechanism of CRAO is related to immune complex-mediated "vasculitis", which is typically associated with neuropsychiatric lupus. However, the literature review identified antiphospholipid antibody syndrome (APS) in only 6 of 19 patients, indicating that other mechanisms besides APS are associated with CRAO. Systemic immunosuppression and anticoagulants are required for the treatment of this severe vaso-occlusive retinopathy. Early recognition and aggressive intervention may prevent severe loss of vision.

Bilateral Combined Central Retinal Artery and Vein Occlusion in a Child with Purtscher Retinopathy: A Case Report and Review of the Literature

Purtscher retinopathy is a hemorrhagic and vaso-occlusive vasculopathy that results from head trauma. Typically, patients present with sudden onset of painless reduction in visual acuity and a group of retinal findings including retinal hemorrhages, retinal whitening, and optic disc edema. The objectives of the study were to describe the rare occurrence of combined central retinal artery and central vein occlusion in a child with Purtscher retinopathy and to illustrate the course of visual recovery and anatomical changes over 6 months of follow-up. The data were collected from the patient file including circumstances of presentation, visual acuity, anterior segment examination, fundus photography, fundus fluorescein angiography (FFA), B scan ultrasonography (B scan), and optical coherence tomography (OCT). Follow-ups over a 6-month period with repeated imaging were documented. A 6-year-old boy presented with a complaint of bilateral vision loss which occurred 2 days after falling out of high bed. On examination, visual acuity was hand motion bilaterally. External and anterior segments exhibited regular examination, apart from traumatic iritis in both eyes. Posterior segment examination showed intraretinal hemorrhages, retinal whitening bilaterally, and exudative retinal detachment, which was confirmed by OCT and B-scan. FFA of both the eyes showed delayed arterial and venous filling with macular hypoperfusion. Comprehensive systemic workup including brain imaging, hematology, immunology, and uveitis screening was negative. The patient was treated with a high-dose oral steroid. Six months later, his vision improved to 20/40 OD and 20/28 OS. Fundus examination and OCT showed peripheral retinal atrophy but preserved subfoveal outer retinal layers, which explained the visual improvement. Treatment with corticosteroids seems to be effective in reducing retinal edema and hastened visual recovery in patients with Purtscher retinopathy. Cilioretinal artery sparing can preserve the central vision in cases with combined artery and vein occlusion.

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.