Vascular risk factors for central retinal artery occlusion

Central Retinal Artery Occlusion in Young Adults at High Altitude: Thin Air, High Stakes

Rana, Vipin, Pradeep Kumar, Sandeepan Bandopadhyay, Vijay K. Sharma, Meenu Dangi, Dattakiran Joshi, Sanjay Kumar Mishra, Satyabrat Srikumar, and V.A. Arun. Central retinal artery occlusion in young adults at high altitude: thin air, high stakes. High Alt Med Biol. 00:000-000, 2024.-We present five cases of young security personnel who were posted at high altitude (HA) for a duration of at least 6 months and presented with a sudden decrease of vision in one eye. The diagnosis of central retinal artery occlusion (CRAO) was made in all patients. Fundus fluorescein angiography and optical coherence tomography of the macula supported the diagnosis. None of these cases had any preexisting comorbidities. Erythrocytosis was noticed in all patients, and two of them had hyperhomocysteinemia. Four out of five patients showed either middle cerebral artery or internal carotid artery (ICA) thrombosis on computed tomography angiography. The patients were managed by a team of ophthalmologist, hematologist, vascular surgeon, and neurologist. In cases of incomplete ICA occlusion, patients were managed surgically. However, in the case of complete ICA occlusion, management was conservative with antiplatelet drugs. This case series highlights HA-associated erythrocytosis and hyperhomocysteinemia as important risk factors for CRAO in young individuals stationed at HA.

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.

Incidence of central retinal artery occlusion peaks in winter season

Introduction

Stroke incidence exhibits seasonal trends, with the highest occurrences observed during winter. This study investigates the incidence of central retinal artery occlusion (CRAO), a stroke equivalent of the retina, and explores its monthly and seasonal variations, as well as potential associations with weather and ambient air pollutants.

Methods

A retrospective search of medical records spanning 15 years (January 2008-December 2022) was conducted at the University Eye Hospital Tübingen, Germany, focusing on diagnosed cases of CRAO. Incidences were evaluated on a monthly and seasonal basis (winter, spring, summer, fall). Weather data (temperature, precipitation, atmospheric pressure) and concentrations of ambient air pollutants [fine particulate matter (PM2.5), coarse particulate matter (PM10), nitrogen dioxide (NO2), and ozone (O3)], were analyzed for a potential association with CRAO incidence.

Results

Out of 432 patients diagnosed with CRAO between 2008 and 2022, significantly varying incidences were observed monthly (p = 0.025) and seasonally (p = 0.008). The highest rates were recorded in February and winter, with the lowest rates in June and summer. Concentrations of NO2, PM2.5 and lower ambient air temperature (average, minimum, maximum) showed significant correlations with CRAO incidence.

Discussion

This comprehensive 15-year analysis reveals a pronounced winter peak in CRAO incidence, with the lowest occurrences in summer. Potential associations between CRAO incidence and ambient air pollutants and temperature underscore the importance of considering seasonal trends and call for further investigations to elucidate contributing factors, potentially leading to targeted preventive strategies and public health interventions.

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.

Central Retinal Artery Occlusion Due to Subperiosteal Orbital Abscess Caused by Acute Sinusitis in a Child: A Case Report

Central retinal artery occlusion (CRAO) is an ophthalmic emergency and has poor visual prognosis. It is commonly found in elderly people and very rare in child. We reported an 8-year-old girl who suffered from acute sinusitis, periorbital swelling, and the visual acuity of her right eye was only light perception. She was diagnosed with CRAO, SPOA (subperiosteal orbital abscess), and acute sinusitis. Emergency treatments including surgery, antibiotics, glucocorticoids, intraocular-pressure-lowering drugs, and vasodilators were taken immediately in order to save the eyesight. The visual acuity of the right eye returned to 20/400. Conclusions: Severe intraorbital complications of acute sinusitis can lead to CRAO. Timely drainage, strong antibiotics, and glucocorticoids are the most effective methods for the treatments.

Retinal Vascular Occlusion Risks in High Blood Pressure and the Benefits of Blood Pressure Control

PURPOSE

This study aimed to evaluate the association of retinal vascular occlusion, including retinal vein occlusion (RVO) and retinal artery occlusion (RAO), with stages of hypertension.

DESIGN

Nationwide, population-based retrospective cohort study.

METHODS

Based on baseline blood pressure (BP) as defined by the 2017 American College of Cardiology/American Heart Association guideline, participants were categorized into 4 BP groups. For the BP change measurement, BP groups were defined based on the combination of baseline and follow-up BP categories. The composite retinal vascular occlusion events and hazard ratios (HRs) of retinal vascular occlusion according to BP groups were estimated.

RESULTS

With normal BP as the reference, multivariate-adjusted HRs for retinal vascular occlusion were significantly higher than in other BP groups, showing much higher HRs in stage 2 hypertension than in stage 1 (HR, 1.10 for elevated BP; 1.07 for stage 1 hypertension; and 1.32 for stage 2 hypertension). Individual disease analysis showed consistent statistical significance in RVO, whereas RAO showed nonsignificant results. Lowering BP significantly decreased the HRs of retinal vascular occlusion in both stage 1 and stage 2 hypertension (HR, 0.88 and 0.73, respectively). However, once hypertension was diagnosed, the risk of retinal vascular occlusion was higher compared to that in the normal BP groups.

CONCLUSIONS

Elevated BP, stage 1 hypertension, and stage 2 hypertension were all associated with higher retinal vascular occlusion risks than was normal BP. Controlling hypertension appears to reduce the risk of subsequent retinal vascular occlusion; however, the incidence rate was still be significantly higher than that in persons who maintained a normal BP.

Assessment of Red Cell Distribution Width, Platelet/lymphocyte Ratio, Systemic Immune-inflammation Index, and Neutrophil/lymphocyte Ratio Values in Patients with Central Retinal Artery Occlusion

PURPOSE

To evaluate complete blood count (CBC)-derived inflammatory indices in central retinal artery occlusion (CRAO).

METHODS

A total of 42 patients with CRAO (CRAO group) and 42 age- and sex-matched subjects without CRAO (Control group) were included. CBC parameters including red cell distribution width (RDW) levels were assayed. Platelet/lymphocyte ratio (PLR), systemic immune-inflammation index (SII) and neutrophil/ lymphocyte ratio (NLR) were calculated.

RESULTS

RDW, PLR, SII and NLR values were significantly higher in CRAO group than control group [15.2 ± 1.47% vs 13.96 ± 1.13% (p < .001), 127.94 ± 48.21 vs 101.16 ± 24.84 (p = .008), 667.11 ± 357.84 vs 493.44 ± 207.07 (p = .008), 2.70 ± 1.27 vs 2.13 ± 0.83 (p = .018), respectively]. In multivariate analysis only RDW was independent predictor for CRAO (OR 2.317, p < .001). On ROC analysis, area under curve of RDW, PLR, SII, and NLR for CRAO were 0.761, 0.685, 0.622 and 0.618, respectively.

CONCLUSION

RDW seems superior to other inflammatory indices to predict CRAO.

Hemi- and Central Retinal Vein Occlusion Associated with COVID-19 Infection in Young Patients without Known Risk Factors

PURPOSE

Venous thromboembolic complications have been reported in association with coronavirus disease 2019 (COVID-19) infection. We raised awareness regarding a potential temporal association between COVID-19 infection and retinal vein occlusion (RVO).

DESIGN

Multicenter, retrospective, nonconsecutive case series.

SUBJECTS

Patients presenting with hemi-RVO (HRVO) or central RVO (CRVO) between March 2020 and March 2021, with confirmed COVID-19 infection, were included. The exclusion criteria were as follows: age >50 years, hypertension, diabetes, glaucoma, obesity, underlying hypercoagulable states, and those requiring intubation during hospitalization.

METHODS

This was a multicenter, retrospective, nonconsecutive case series including patients presenting with hemi-RVO (HRVO) or central RVO (CRVO) between March 2020 and March 2021, with confirmed COVID-19 infection. The exclusion criteria were as follows: age >50 years, hypertension, diabetes, glaucoma, obesity, underlying hypercoagulable states, and those requiring intubation during hospitalization.

MAIN OUTCOME MEASURES

Ophthalmic findings, including presenting and final visual acuity (VA), imaging findings, and clinical course.

RESULTS

Twelve eyes of 12 patients with CRVO (9 of 12) or HRVO (3 of 12) after COVID-19 infection were included. The median age was 32 years (range, 18-50 years). Three patients were hospitalized, but none were intubated. The median time from COVID-19 diagnosis to ophthalmic symptoms was 6.9 weeks. The presenting VA ranged from 20/20 to counting fingers, with over half (7 of 12) having a VA of ≥20/40. OCT revealed macular edema in 42% of the eyes; of these, 80% (4 of 5) were treated with anti-VEGF injections. Ninety-two percent (11 of 12) had partial or complete resolution of ocular findings at final follow-up. Four eyes (33%) had retinal thinning, as determined using OCT, by the end of the study interval. The final VA ranged from 20/20 to 20/60, with 11 of the 12 (92%) eyes achieving a VA of ≥20/40 at a median final follow-up period of 13 weeks (range, 4-52 weeks).

CONCLUSIONS

Although we acknowledge the high seroprevalence of COVID-19 and that a causal relationship cannot be established, we reported this series to raise awareness regarding the potential risk of retinal vascular events due to a heightened thromboinflammatory state associated with COVID-19 infection.

Central Retinal Artery Occlusion: Current Practice, Awareness and Prehospital Delays in Switzerland

Background and Purpose

Central retinal artery occlusion (CRAO) often leads to permanent monocular blindness. Hence, early recognition and rapid re-perfusion is of paramount importance. This study aims to describe prehospital pathways in CRAO compared to stroke and study the knowledge about CRAO.

Methods

(1) Description of baseline characteristics, prehospital pathways/delays, and acute treatment (thrombolysis/thrombectomy vs. standard of care) of patients with CRAO and ischemic stroke registered in the Swiss Stroke Registry. (2) Online survey about CRAO knowledge amongst population, general practitioners (GPs) and ophthalmologists in Eastern Switzerland.

Results

Three hundred and ninety seven CRAO and 32,816 ischemic stroke cases were registered from 2014 until 2019 in 20 Stroke Centers/Units in Switzerland. In CRAO, 25.6% arrived at the hospital within 4 h of symptom onset and had a lower rate of emergency referrals. Hence, the symptom-to-door time was significantly longer in CRAO compared to stroke (852 min. vs. 300 min). The thrombolysis/thrombectomy rate was 13.2% in CRAO and 30.9% in stroke. 28.6% of the surveyed population recognized CRAO-symptoms, 55.4% of which would present directly to the emergency department in contrast to 90.0% with stroke symptoms. Almost 100% of the ophthalmologist and general practitioners recognized CRAO as a medical emergency and 1/3 of them considered IV thrombolysis a potentially beneficial therapy.

Conclusions

CRAO awareness of the general population and physician awareness about the treatment options as well as the non-standardized prehospital organization, seems to be the main reason for the prehospital delays and impedes treating CRAO patients. Educational efforts should be undertaken to improve awareness about CRAO.

Central Retinal Artery Occlusion Is Related to Vascular Endothelial Injury and Left Ventricular Diastolic Dysfunction

Central retinal artery occlusion (CRAO) is an emergency state characterized by sudden, painless vision impairment. Patients with CRAO have an increased risk of cardiovascular events, including stroke, likely related to vascular endothelial damage. Therefore, we investigated flow-mediated dilatation (FMD) of the brachial artery as a marker of endothelial dysfunction, intima-media complex thickness (IMT) of the common carotid artery, pointing to the arterial wall atherosclerotic alteration, and transthoracic echocardiographic parameters in 126 consecutive CRAO patients (66 men [52.4%], median age 55 years) and 107 control participants (56 men [52.3%], matched by age, sex, and body mass index). Most CRAO patients (n = 104, 82.5%) had at least one internal medicine comorbidity, mainly hypercholesterolemia and hypertension, which coexisted in one-fourth of them. Furthermore, they had a 38.2% lower relative increase of FMD (FMD%) and a 23.1% thicker IMT compared to the controls (p < 0.001, both, also after adjustment for potential confounders). On echocardiography, the CRAO group was characterized by increased dimensions of the left atrium and thicker left ventricular walls, together with impaired left ventricular diastolic function. CRAO is related to vascular endothelial damage, atherosclerosis, and left ventricular diastolic cardiac dysfunction. Thus, non-invasive ultrasound assessments, such as FMD%, IMT, and echocardiography, may be helpful in screening patients with increased CRAO risk, particularly those with other comorbidities.

Central retinal artery occlusion with cilioretinal sparing in a patient with Eisenmenger syndrome

A young boy in his 20s presented with sudden diminution of vision in right eye 2 days ago. Best-corrected visual acuity was hand movement in right eye and 20/20 in left eye. Funduscopy demonstrated diffuse retinal opacification and swelling at the posterior pole with a cherry red spot at the macula. There was sparing of the superonasal macula with a patent cilioretinal artery. OCT showed diffuse inner retinal thickening of the temporal macula. He was diagnosed as central retinal artery occlusion with cilioretinal sparing in right eye. He was a known case of Eisenmenger syndrome secondary to a large congenital ventricular septal defect. Medical history was notable for prominent pulmonary hypertension and shortness of breath on exertion. Physical examination revealed a harsh systolic murmur. Extremities showed digital erythema and severe clubbing. Chest X-ray demonstrated cardiomegaly. Laboratory examination revealed haemoglobin-220 g/L, haematocrit-60%, serum iron-20 µg/dL.

Androgen Deprivation Therapy for Prostate Cancer Did Not Increase the Risk of Retinal Vascular Occlusion: A Population-Based Cohort Study

This study aimed to evaluate the effect of androgen deprivation therapy (ADT) on retinal vascular occlusion (RVO) development in patients with prostate cancer, using data from Taiwan’s National Health Insurance Research Database. A total of 1791, 1791, and 3582 patients were enrolled in the prostate cancer with ADT group, prostate cancer without ADT group, and the control group, respectively. The primary outcome was RVO occurrence, according to diagnostic codes. Cox proportional hazard regression was used to determine the adjusted hazard ratio (aHR) and 95% confidence interval (CI) of ADT and other covariates for RVO incidence. After a follow-up interval of up to 18 years, the patients with prostate cancer who received ADT showed significantly lower RVO incidence than the control group (aHR: 0.191, 95% CI: 0.059–0.621, p = 0.0059), after adjusting for multiple confounders. Hypertension was related to higher RVO incidence (aHR: 2.130, 95% CI: 1.127–4.027, p = 0.0199). Our overall results showed that using ADT for prostate cancer did not lead to a greater risk of RVO development. In fact, the patients with prostate cancer who received ADT had lower RVO incidence than those who did not receive ADT.

A review of the management of central retinal artery occlusion

Central retinal artery occlusion (CRAO), the ocular analog of a cerebral stroke, is an ophthalmic emergency. The visual prognosis for overall spontaneous visual recovery in CRAO is low. Furthermore, the risk of future ischemic heart disease and cerebral stroke is increased due to the underlying atherosclerotic risk factors. There is currently no guideline-endorsed treatment for CRAO. This review will describe the anatomy, pathophysiology, epidemiology, and clinical features of CRAO, and investigate the current and future management strategies.

Cerebral angiographic features of central retinal artery occlusion patients treated with intra-arterial thrombolysis

BACKGROUND

Central retinal artery occlusion (CRAO) is an ischemic stroke of the eye. The atherosclerotic lesions in the intracranial segment of the carotid artery (CA) and the ophthalmic artery (OphA) are not well defined. We aimed to investigate the cerebral angiographic features of CRAO patients and assess the relationship between the angiographic features and outcomes after intra-arterial thrombolysis (IAT).

METHODS

We included 101 acute non-arteritic CRAO patients treated with IAT. We analyzed the detailed angiographic features of the OphA and ipsilateral CA, visual acuity, fundus photography, and fluorescein angiography.

RESULTS

Of the 101 patients, 38 patients (37.6%) had steno-occlusive lesions in the OphA, and 62 patients (61.4%) had atherosclerotic lesions in the ipsilateral CA. The patients with a higher degree of stenosis in the OphA showed a higher degree of stenosis (P=0.049) and a more severe morphology of plaque (P=0.000) in the ipsilateral CA. Additionally, although the visual outcome was not associated with these angiographic features, the lower degree of stenosis and less severe morphology of plaque in the ipsilateral CA resulted in a significant improvement in early reperfusion rate (P=0.018 and P=0.014, respectively) and arm-to-retina circulation (P=0.016 and P=0.002, respectively) of the eye after IAT.

CONCLUSIONS

There was a significant correlation in the severity of steno-occlusive lesions between the OphA and the ipsilateral CA in patients with CRAO. The patients with less severe angiographic features in the CA showed a more improved retinal reperfusion after IAT. The angiographic findings in the CA may serve as a predictive marker for the vessel integrity of the OphA and recanalization outcome after IAT.

Internal limiting membrane detachment in acute central retinal artery occlusion: a novel prognostic sign seen on OCT

Background

To present a series of acute central retinal artery occlusion (CRAO) cases showing internal limiting membrane detachment (ILMD) on optical coherence tomography (OCT) and to describe the possible etiopathogenesis and outcomes associated with it.

Methods

Demographic and OCT features of patients with acute CRAO were analysed retrospectively. OCT parameters noted were posterior vitreous opacities, ILMD, inner retinal layer stratification, hyperreflectivity and thickening, cystoid macular edema, neurosensory detachment. Eyes were grouped into Group (1) CRAO with ILMD; Group (2) CRAO with no ILMD.

Results

A total of 28 eyes of acute CRAO who had undergone OCT scans at the time of the acute episode were identified. Out of these, ILMD was noted in 5 eyes. The study findings suggested that cases of acute CRAO with ILMD are associated with poor presenting visual acuity and have more severe signs of retinal hypoperfusion on OCT, like inner retinal thickening, inner retinal hyperreflectivity and loss of inner retinal layer stratification. Patients with ILMD have poor final visual acuity and thinning and atrophy or necrosis of the inner retinal layers.

Conclusion

ILMD can occur in acute CRAO due to total retinal artery occlusion and severe retinal hypoperfusion. The presence of ILMD on OCT can be considered a sign of poor prognosis in cases of acute CRAO.

Trial registration: Not applicable.

Hyperbaric Oxygen Therapy for Central Retinal Artery Occlusion: Patient Selection and Perspectives

The central retinal artery occlusion (CRAO) is a rare ophthalmological emergency that can occur in the eye. CRAO can affect persons of any age, however it is most common in people over the age of 60. CRAO is associated with a number of risk factors, including giant cell arteritis, carotid artery atherosclerosis, cardiogenic emboli, hypertension, smoking, diabetes, and thromboembolic disease. The chance of each of these etiologies being present is assessed during the course of the investigation. Hyperbaric oxygen treatment (HBOT) is classified by the American Heart Association for CRAO at level IIb. In accordance with that, HBOT might be considered for the treatment of such a severe condition. HBOT can maintain retinal oxygenation during ischemic events by allowing oxygen to diffuse through choroidal capillaries that have been exposed to elevated partial pressures of oxygen. As a result, ischemia-related damage is reversed if applied within proper time frame. The amount of time that has passed prior to initiation of HBOT is considered to be the most critical factor in determining the best visual prognosis. According to the Undersea and Hyperbaric Medical Society, patients who are identified with CRAO after the onset of symptoms should be evaluated for HBOT within 24 hours. HBOT has the advantage of having a low risk profile, and it can be utilized to improve visual outcomes in proper patients.

Phosphodiesterase Type 5 Inhibitors and Visual Side Effects: A Narrative Review

Phosphodiesterase type 5 inhibitors such as sildenafil citrate and tadalafil are well known for the treatment of erectile dysfunction. However, their use in the presence of pulmonary hypertension can cause ophthalmologic side effects, including non-arteritic optic ischemic neuropathy, chorioretinopathy, glaucoma, and optic atrophy. The present review aimed to identify these visual side effects and provide recommendations. We identified articles published from January 2000 to March 2019 on diseases arising from the management of sexual dysfunction in urology or pulmonary hypertension in pneumonia that could cause pathologic alterations in eye structure based on a literature search of the MEDLINE electronic database using keywords for the most common adverse effects and different kinds of phosphodiesterase 5 inhibitors. After applying the exclusion criteria, we selected 36 of the 77 articles initially identified to write the narrative review and added 20 additional articles to completely describe the pathological entities. Phosphodiesterase type 5 inhibitors can cause side effects in the eye including ocular surface abnormalities, increased intraocular pressure and glaucoma, uveitis, non-arteritic ischemic neuropathy, chorioretinopathy, retinal occlusion, and visual field changes. There is an increased need for well-performed studies to better understand these side effects, which are common due to the wide use of sildenafil.

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

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

Management of Acute Central Retinal Artery Occlusion, a "Retinal Stroke": An Institutional Series and Literature Review

OBJECTIVES

Acute central retinal artery occlusion (CRAO) is an ophthalmologic emergency that often results in permanent vision loss. Over 25% are associated with acute cerebral ischemia. In the absence of existing Level I treatment options, this study aims to examine institutional practice patterns and review the literature to develop a formalized approach to the treatment of CRAO in the era of ischemic stroke protocols.

MATERIALS AND METHODS

This is a retrospective review of institutional practices in the workup and treatment of patients diagnosed with acute non-arteritic (NA) CRAO at a single center from January 2017 to August 2020.

RESULTS

Of 91 patients managed for acute NA-CRAO, 62.6% were male and average age was 66.4 years. Only 20.9% of patients presented within 4 h of symptom onset. 12.1% of patients had evidence of acute stroke on MRI, and 27.5% had ipsilateral internal carotid artery stenosis >50%. Half (52.7%) did not receive any acute treatment for CRAO, excluding antiplatelet/anticoagulation. 48.5% of patients undergoing acute medical treatment had improved visual acuity compared to 29.4% without treatment (p=0.14).

CONCLUSIONS

There is a lack of clear protocol for the management of NA-CRAO. While not reaching statistical significance, our experience mirrors the literature with patients undergoing medical treatment demonstrating improved visual acuity over those without treatment. Given the presence of acute ischemic stroke, carotid disease, and/or stroke risk factors in over 25% of patients with CRAO, multidisciplinary involvement and modern stroke algorithms should be considered for this disease.

Arterial Occlusions to the Eye: From Retinal Emboli to Ocular Ischemic Syndrome

: Abstract: A loss or lack of blood supply to the eye can result in acute loss of vision. The site of ischemia may be at the level of the retinal arterioles, the central retinal artery, or further back at the ophthalmic and internal carotid artery. Recognizing the symptoms and signs are important to help prevent permanent ischemic and irreversible blindness. The objective of this review article is to provide the general ophthalmologists with information on how to recognize the symptoms and to best manage these patients. The management is to investigate for the cause of the transient monocular visual loss and to apply secondary prevention to address atherosclerotic risk factors to prevent further ischemic events like a stroke.

Correlation of the history of stroke and the retinal artery occlusion: a nested case-control study

AIM

To analyze the systemic factors including stroke history related to the retinal artery occlusion (RAO).

METHODS

Patients with an exact diagnosis of RAO in the medical database of the Kailuan Corporation were identified as the case group. Five patients without RAO were added for each case from the Kailuan Study and matched for sex and age (age±2) as the control group. The Kailuan Study is a general population-based cohort study in northern China, in which a total of 101 510 individuals (81 110 men) aged 18-98y were recruited to participate in the study. And the participants were bi-annually re-examined. The database of both groups was from Kailuan study of 2010 cohort. All the information, including the demographic characteristics, lifestyle behaviors, medical comorbidities, medical history, family medical history, drug usage, anthropometric measurements, blood pressure measurement, blood sample laboratory assessment, urine tests, and other physical examinations were all collected. A retrospective nested case-control method was used for this study. Conditional multivariate logistic regression was used to analyze the risk factors with SPSS 13.0 software and SAS 9.3 software.

RESULTS

A total of 45 patients were included as the case group, and the control group included 225 patients. In the case group, 28 patients (62.2%) had a central retinal artery occlusion (CRAO), and 17 patients (37.8%) had a branch retinal artery occlusion (BRAO). A total of 18 patients (40.0%) had a stroke before the RAO (mean 4.04±3.88y before the RAO), and 31 patients (81.6%) had infarctions or malacia identified by the cranial computed tomography (CT) scans. The basal ganglia and centrum semiovale were the most frequently involved regions. Plaques in the common carotid artery were present in 32 patients (88.9%). Conditional multivariate logistic regression analysis showed that the RAO was found to be associated with the history of stroke (P=0.0023, OR=28.794; 95%CI: 3.322-249.586).

CONCLUSION

A history of stroke can significantly increase the incidence of RAO. Exists of plaque in the carotid artery is mean more than its severe stenosis for RAO.

Development of visual acuity under hyperbaric oxygen treatment (HBO) in non arteritic retinal branch artery occlusion

PURPOSE

Nonperfusion of retinal tissue due to arterial occlusion leads inevitably to mostly irreversible retinal damage. Until today no evidence-based treatment exists. Inhalation of 100% oxygen at high atmospheric pressure causes an increased solubility of oxygen in the blood that helps the retinal tissue to survive through diffusion in case of an artery occlusion till vascular recanalization occurs. Hence the purpose of this study is to compare the visual outcome in patients with retinal branch artery obstruction treated with hyperbaric oxygen versus patients treated with hemodilution only.

METHODS

Non-randomized, monocentric, retrospective study. Patients with diagnosis of non-arteritic retinal branch artery occlusion (BRAO) treated with hyperbaric oxygen therapy between 1997 and 2017. Exclusion criteria were central retinal artery occlusion, presence of a cilioretinal artery and arteritic cases. The control group was matched based on visual acuity (VA) at admission, age, and delay between symptoms and beginning of clinical care.

RESULTS

The control group and the matching oxygen group contained 14 patients each. Initial VA in the matched HBO group was 0.18 ± 0.19 and 0.23 ± 0.19 in the control group (p = 0.57). Final VA at discharge was 0.69 ± 0.29 in the matched oxygen group and 0.32 ± 0.23 in the control group (p = 0.0009). HBO-treated patients had a significant visual increase compared with the control group. The most common comorbidities were arterial hypertension and vascular sclerosis.

CONCLUSION

HBO treatment appears to have a beneficial effect on visual outcome in patients with retinal branch artery occlusion. HBO treatment could be a rescue therapy at an early stage of BRAO, especially to bridge the time of a potential reperfusion. However, further, prospective, randomized clinical trials are required to verify this assumption.

Acute Vascular Ischemic Events in Patients With Central Retinal Artery Occlusion in the United States: A Nationwide Study 2003-2014

PURPOSE

Central retinal artery occlusion (CRAO) confers a high risk of acute vascular ischemic events, including stroke and myocardial infarction (MI). Understanding the burden and risk factor profile of these ischemic events can serve as a valuable guide for ophthalmologists in the management and appropriate referral of these patients.

DESIGN

Retrospective cross-sectional study.

METHODS

The Nationwide Inpatient Sample (NIS) was queried to identify all inpatient admissions with a diagnosis of CRAO in the United States between the years 2003 and 2014. The primary outcome measure was the incidence of in-hospital acute vascular ischemic events.

RESULTS

There were an estimated 17 117 CRAO inpatient admissions. The mean age was 68.4 ± 0.1 years and 53% of patients were female. The incidence of in-hospital stroke and acute MI were 12.9% and 3.7%. The incidence of stroke showed an increasing trend over the years, almost doubling in 2014 in comparison to 2003 (15.3% vs 7.7%). The combined risk of in-hospital stroke, transient ischemic attack, acute MI, or mortality was 19%. Female sex, hypertension, carotid artery stenosis, aortic valve disease, smoking, and alcohol dependence or abuse were positive predictors of in-hospital stroke.

CONCLUSION

There is a significant burden of vascular risk factors, associated with an increased risk of in-hospital stroke, acute MI, and death in CRAO patients. The risk of CRAO-associated stroke is highest in women and in those with a history of hypertension, carotid artery stenosis, aortic valve disease, smoking, or alcohol abuse.

Early Identification of Central Retinal Artery Occlusion Using Point-of-care Ultrasound

A 69-year-old woman with a history of untreated hypertension presented with acute-onset monocular vision loss. Initial workup was delayed due to lack of immediate specialty consultation and dilated funduscopic exam. Point-of-care ultrasound in the emergency department identified a small hyperechoic structure within the distal area of the central retinal artery; in conjunction with specialty ophthalmologic evaluation in a tertiary care center, the diagnosis of central retinal artery occlusion was made. The patient was admitted to the neurology service for stroke risk stratification and was discharged in stable condition with re-initiation of her antihypertensive medication regimen.

Is Management of Central Retinal Artery Occlusion the Next Frontier in Cerebrovascular Diseases?

Central retinal artery occlusion (CRAO) is a medical emergency that, if not treated, may result in irreversible loss of vision. It continues to be an important cause for acute painless loss of vision. Amaurosis fugax or "transient CRAO" has long been considered an equivalent of transient cerebral ischemic event. Animal models, in addition to data from retrospective and randomized clinical studies, provide valuable insights into the time interval for irreversible retinal ischemia. Subset analyses from 2 large studies of patients with CRAO show benefit from treatment with thrombolysis within 6 hours from symptoms onset. Significant workflow improvements after the intra-arterial therapy trials for acute ischemic stroke have occurred world over in last 5 years. Patients with CRAO are uniquely suited to receive maximum benefits from the changes in workflow for treatment of patient's acute ischemic stroke. Just as in clinical triage of acute ischemic stroke, correct and timely diagnosis of patients with CRAO may help in preventing visual loss. The approach to acute ocular ischemia should mimic that used for acute brain ischemia. Comprehensive stroke centers would be ideal triage centers for these patients in view of availability of multidisciplinary participation from vascular neurology, neuroendovascular surgery, and ophthalmology. Time is Retina!

Treatment of Nonarteritic Acute Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is an event most often caused by an embolus originating in the ipsilateral carotid artery, aortic arch, or heart. CRAO may result from partial or complete occlusion of the central retinal artery (CRA), which acts as the primary blood supply to the inner neurosensory retina, and typically results in profound vision loss and permanent visual disability. No consensus has emerged regarding the optimal treatment of CRAO. All proposed treatments are of questionable efficacy and many have uncertain risk profiles. In certain circumstances, thrombolysis may be attempted as a treatment option; however, the evidence to support broad use of thrombolytics in the treatment of acute CRAO remains elusive. It is known that the risk factors that predispose to other cardiovascular and cerebrovascular events are often present in CRAO. Accordingly, identification of patients at highest risk of stroke and secondary prevention of ischemic events remains the primary focus of management. This review offers a summary of the clinical presentation, diagnosis, and prognosis of CRAO, with an emphasis on treatment options.

Acute retinal arterial ischemia

Acute retinal arterial ischemia, which includes transient monocular vision loss (TMVL), branch retinal artery occlusion (BRAO), central retinal artery occlusion (CRAO) and ophthalmic artery occlusion (OAO), is most commonly the consequence of an embolic phenomenon from the ipsilateral carotid artery, heart or aortic arch, leading to partial or complete occlusion of the central retinal artery (CRA) or its branches. Acute retinal arterial ischemia is the ocular equivalent of acute cerebral ischemia and is an ophthalmic and medical emergency. Patients with acute retinal arterial ischemia are at a high risk of having further vascular events, such as subsequent strokes and myocardial infarctions (MIs). Therefore, prompt diagnosis and urgent referral to appropriate specialists and centers is necessary for further work-up (such as brain magnetic resonance imaging with diffusion weighted imaging, vascular imaging, and cardiac monitoring and imaging) and potential treatment of an urgent etiology (e.g., carotid dissection or critical carotid artery stenosis). Since there are no proven, effective treatments to improve visual outcome following permanent retinal arterial ischemia (central or branch retinal artery occlusion), treatment must focus on secondary prevention measures to decrease the likelihood of subsequent ischemic events.

Review of the association between retinal microvascular characteristics and eye disease

Computerized retinal imaging technologies enable the static and dynamic measurement of a range of retinal microvascular parameters. Large population-based studies have reported associations between these microvascular indices and various ophthalmic diseases including diabetes, age-related macular degeneration, retinal artery embolism, retinal vein occlusion, glaucoma and non-glaucomatous optic neuropathies. Increasingly, sophisticated imaging and analysis techniques have the potential to provide relevant clinical information regarding disease risk and progression; however, further studies are required to verify associations and strengthen the predictive power of these techniques. We summarize the current state of knowledge regarding retinal microvascular characteristics and eye disease.

[Retinal artery occlusion]

Retinal artery occlusion leads to profound visual impairment in the affected eye. It is rarely caused by local ophthalmic pathologies. Most patients present with a large number of cardio- and cerebrovascular risk factors. Visual loss is the leading symptom in central retinal artery occlusion (CRAO), whereas a circumscribed visual field defect is claimed in branch retinal artery occlusion (BRAO). Although many attempts have been made to improve the course of the disease, no effective therapy is available. There is some hope that intravenous fibrinolysis could influence the natural course but the therapeutic window is small (ca. 4.5 h), and treatment efficacy is still not proven. It is important for ophthalmologists to guide the patients to a comprehensive and prompt neurological and cardiological diagnostic work-up.

Update on the Management of Central Retinal Artery Occlusion

Central retinal artery occlusion (CRAO) is caused by partial or complete occlusion of the central retinal artery, most commonly by an embolus from the ipsilateral carotid artery, aortic arch, or heart, and is the ocular equivalent of an acute cerebral ischemic event. The risk factors for a CRAO and acute cerebral ischemia are very similar, if not identical. Because no current therapeutic intervention has been shown to improve visual outcomes compared with the natural history of CRAO, management of CRAO should be focused on secondary prevention of vascular events, such as cerebral ischemia, myocardial infarction, and cardiovascular death.

Perioperative Retinal Artery Occlusion: Risk Factors in Cardiac Surgery from the United States National Inpatient Sample 1998-2013

PURPOSE

To study the incidence and risk factors for retinal artery occlusion (RAO) in cardiac surgery.

DESIGN

Retrospective study using the National Inpatient Sample (NIS).

METHODS

The NIS was searched for cardiac surgery. Retinal artery occlusion was identified by International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. Postulated risk factors based on literature review were included in multivariate logistic models.

MAIN OUTCOME MEASURES

Diagnosis of RAO.

RESULTS

A total of 5 872 833 cardiac operative procedures were estimated in the United States from 1998 to 2013, with 4564 RAO cases (95% confidence interval [95% CI], 4282-4869). Nationally estimated RAO incidence was 7.77/10 000 cardiac operative procedures from 1998 to 2013 (95% CI, 7.29-8.29). Associated with increased RAO were giant cell arteritis (odds ratio [OR], 7.73; CI, 2.78-21.52; P < 0.001), transient cerebral ischemia (OR, 7.67; CI, 5.31-11.07; P < 0.001), carotid artery stenosis (OR, 7.52; CI, 6.22-9.09; P < 0.001), embolic stroke (OR, 4.43; CI, 3.05-6.42; P < 0.001), hypercoagulability (OR, 2.90; CI, 1.56-5.39; P < 0.001), myxoma (OR, 2.43; CI, 1.39-4.26; P = 0.002), diabetes mellitus (DM) with ophthalmic complications (OR, 1.89; CI, 1.10-3.24; P = 0.02), and aortic insufficiency (OR, 1.85; CI, 1.26-2.71; P = 0.002). Perioperative bleeding, aortic and mitral valve surgery, and septal surgery increased the odds of RAO. Negatively associated with RAO were female gender (OR, 0.77; CI, 0.66-0.89; P < 0.001), thrombocytopenia (OR, 0.79; CI, 0.62-1.00; P = 0.049), acute coronary syndrome (OR, 0.72; CI, 0.58-0.89; P = 0.003), atrial fibrillation (OR, 0.82; CI, 0.70-0.95; P = 0.01), congestive heart failure (OR, 0.73; CI, 0.60-0.88; P < 0.001), DM 2 (OR, 0.74; CI, 0.61-0.89; P = 0.001), and smoking (OR, 0.82; CI, 0.70-0.97; P = 0.02).

CONCLUSIONS

Risk factors for RAO in cardiac surgery include giant cell arteritis, carotid stenosis, stroke, hypercoagulable state, and DM with ophthalmic complications; associated with lower risk were female gender, thrombocytopenia, acute coronary syndrome, atrial fibrillation, congestive heart failure, DM 2, and smoking. Surgery in which the heart was opened (e.g., septal repair) versus surgery in which it was not (e.g., CABG) and perioperative bleeding increased the risk of RAO.

Cardiovascular Risk Factors in Central Retinal Artery Occlusion: Results of a Prospective and Standardized Medical Examination

PURPOSE

To analyze the underlying risk factors in patients with nonarteritic central retinal artery occlusion (CRAO) in a well-defined and homogenous group of patients enrolled in the European Assessment Group for Lysis in the Eye (EAGLE) study.

DESIGN

Analysis of the cardiovascular risk factors in a prospective, randomized clinical trial.

PARTICIPANTS

Seventy-seven EAGLE patients with nonarteritic CRAO.

METHODS

Analysis of vascular risk factors and underlying diseases detected by questionnaire and standardized physical examination within 1 month after occlusion.

MAIN OUTCOME MEASURES

The standardized physical examination included carotid Doppler ultrasonography, echocardiography, electrocardiography, blood pressure monitoring, pulse rate, urine analysis, body mass index analysis, and laboratory tests.

RESULTS

Seventy-seven of 84 patients had complete datasets for analysis. Fifty-two (67%) patients had cardiovascular risk factors in their medical history, and comprehensive phenotyping identified at least 1 new risk factor in 60 patients (78%; 95% confidence interval, 67%-87%). Thirty-one (40%) had carotid artery stenosis of at least 70%. Eleven patients experienced a stroke, 5 of those within 4 weeks after the CRAO occurred. Arterial hypertension was found in 56 (73%) patients and was newly diagnosed in 12 (16%) study participants. Cardiac diseases were also highly prevalent (22% coronary artery disease, 20% atrial fibrillation, and 17% valvular heart disease).

CONCLUSIONS

Previously undiagnosed vascular risk factors were found in 78% of all CRAO patients. The most meaningful risk factor was ipsilateral carotid artery stenosis. A comprehensive and prompt diagnostic work-up is mandatory for all CRAO patients.

Ischemic cardiomyopathy revealed by central retinal artery occlusion (CRAO)

Here we report a case of central retinal artery occlusionrevealing an ischemic cardiomyopathy. A 54-year old smoker man presented at the hospital because of sudden visual loss in his left eye. There was cherry-red spot in the macula in his left eye. We performed a fluorescein angiogram and cervical color Doppler. Later investigations revealed an ischemic cardiomyopathy undiagnosed until then.

Anterior chamber paracentesis after central retinal artery occlusion: a tenable therapy?

Background

The goal of this study was to investigate the visual outcome of acute central retinal artery occlusion (CRAO) after current standard therapy with and without paracentesis. In addition, we investigated whether there was a dependence of the resulting visual acuity on the time between first symptoms and implementation of paracentesis. Finally, we analysed risk factors for CRAO.

Methods

We performed a retrospective analysis of data from patients with CRAO who received standard in-patient therapy with and without paracentesis at the Dr. Horst Schmidt Clinics in Wiesbaden, Germany between 2000 and 2012. The primary endpoint was the change of visual acuity 3 days after the initiation of intervention.

Results

Data from 74 patients with CRAO were included in the study. Fifteen patients were treated conservatively and 59 patients received additional paracentesis. Clinically significant improvement of BCVA (logMAR ≥ 0.3) after 3 days was observed in 26.7% of patients without paracentesis, 36.4% of patients with paracentesis within 6 hours, 20% of patients with paracentesis within 7–24 hours, and 23.1% of patients with paracentesis more than 24 hours after the onset of symptoms. There was no significant difference in the outcome between patients with (BCVA 1.9 ± 0.31) and without paracentesis (BCVA 1.75 ± 0.32) (p = 0.9), nor among the groups with paracentesis (p = 0.8). One patient suffered a lens injury due to the paracentesis, with subsequent need for cataract surgery.

Conclusions

There was no added gain in visual acuity by performing a paracentesis, independent of the time elapsed between first symptoms and the implementation of paracentesis. In the absence of any tangible effectiveness of paracentesis and the inherent risks of paracentesis such as intraocular infection and injury, paracentesis does not appear to be warranted as a treatment of CRAO.

[Systemic conditions associated with central and branch retinal artery occlusions]

INTRODUCTION

Retinal artery occlusions (RAO) are severe conditions threatening vision, affecting the subsequent mortality of these patients.

PATIENTS AND METHODS

We retrospectively reviewed the work-up performed in all patients diagnosed with retinal artery occlusions evaluated in two university hospitals in France (Tours and Angers).

RESULTS

A total of 131 patients (131 eyes) with RAO were included, with a mean age of 69.5years and male predominance (64 %). Central retinal artery occlusion (CRAO) resulted in poor initial visual acuity (90 % less than count fingers), whereas those with branch retinal artery occlusion (BRAO) had better visual acuity (63.6 % better than 20/40). Systemic arterial hypertension (HTN) was the most common associated risk factor. Carotid stenosis was found in 50 % of cases, leading to endarterectomy in nine patients (6.9 %), while an underlying cardiac cause was implicated in 14 % of cases. Giant cell arteritis was diagnosed in five patients (3.8 %).

DISCUSSION

Work-up of RAO may detect treatable cardiovascular and systemic conditions, allowing prevention of further ocular recurrence or stroke.

CONCLUSION

Etiologic work-up of retinal arterial occlusion can diagnose potentially treatable underlying systemic conditions, such as giant cell arteritis, cardiac conditions and extracranial cerebrovascular disease. Giant cell arteritis has to be ruled out at the acute phase, while the role and timing of semi-urgent testing (supra-aortic Doppler echography, echocardiography, electrocardiography, lab work-up) or delayed testing (transesophageal echocardiography, brain imaging) have yet to be determined.

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

Central retinal artery occlusion (CRAO) is an ophthalmic emergency and the ocular analogue of cerebral stroke. Best evidence reflects that over three-quarters of patients suffer profound acute visual loss with a visual acuity of 20/400 or worse. This results in a reduced functional capacity and quality of life. There is also an increased risk of subsequent cerebral stroke and ischaemic heart disease. There are no current guideline-endorsed therapies, although the use of tissue plasminogen activator (tPA) has been investigated in two randomized controlled trials. This review will describe the pathophysiology, epidemiology, and clinical features of CRAO, and discuss current and future treatments, including the use of tPA in further clinical trials.

Treatment options for central retinal artery occlusion

OPINION STATEMENT

Central retinal artery occlusion (CRAO) is an ocular emergency and is the ocular analogue of cerebral stroke. It results in profound, usually monocular vision loss, and is associated with significant functional morbidity. The risk factors for CRAO are the same atherosclerotic risk factors as for stroke and heart disease. As such, individuals with CRAO may be at risk of ischemic end organ damage such as a cerebral stroke. Therefore, the management of CRAO is not only to restore vision, but at the same time to manage risk factors that may lead to other vascular conditions. There are a number of therapies that has been used in the treatment of CRAO in the past. These include carbogen inhalation, acetazolamide infusion, ocular massage and paracentesis, as well as various vasodilators such as intravenous glyceryl trinitrate. None of these "standard agents" have been shown to alter the natural history of disease definitively. There has been recent interest shown in the use of thrombolytic therapy, delivered either intravenously or intra-arterially by direct catheterisation of the ophthalmic artery. Whilst a number of observational series have shown that the recovery of vision can be quite dramatic, two recent randomised controlled trials have not demonstrated efficacy. On the contrary, intra-arterial delivery of thrombolytic may result in an increased risk of intracranial and systemic haemorrhage, while the intravenous use of tissue plasminogen activator (tPA) was not shown to be efficacious within 24 h of symptom onset. Nevertheless, both of these studies have shown one thing in common, and that is for treatment to be effective in CRAO, it must be deployed within a short time window, probably within 6 h of symptom onset. Therefore, while CRAO is a disease that does not have a treatment, nevertheless it needs to follow the same principles of treatment as any other vascular end organ ischaemic disease. That is, to attempt to reperfuse ischemic tissue as quickly as possible and to institute secondary prevention early.

Retinal arterial occlusions in the young: systemic associations in Indian population

Purpose:

To determine the systemic associations in retinal arterial occlusions (RAO) in young Indian individuals less than 40 years of age.

Materials and Methods:

Case records of 32 patients (35 eyes) of less than 40 years, with non-traumatic RAO were analysed. All patients underwent detailed ophthalmic and systemic evaluation including hemogram, lipid profile, coagulation profile, vasculitis screening, carotid Doppler, echocardiogram.

Results:

In the study 21 were males and 11 were females. The age ranged from 11-39 years (Mean 27.6 ± 8.43). Nine (28%) patients were below 20 years of age. Among 35 eyes, 28 (80%) had central retinal artery occlusion (CRAO), three (8.6%) had branch retinal artery occlusion (BRAO), two (5.7%) each had cilio-retinal (CLAO) and hemi-retinal artery occlusion (HRAO). Vision ranged from no perception of light to 20/20. On systemic evaluation, in 21 (65.6%) patients a hypercoagulable state was responsible for the RAO. Conditions leading to a hypercoagulable state included hyperhomocysteinemia (21.9%), hyperlipidemia (15.6%), anticardiolipin antibody (6.2%), antiphospholipid antibody (6.2%), polycythemia, thrombocytosis, protein S deficiency, use of oral contraceptives and renal disorder (3.1% each). Six (18.7%) patients had cardiac valvular defects. Vasculitis screening was positive in three (9.4%) patients. Two (6.2%) had isolated systemic hypertension. In two (6.2%) patients no abnormality could be detected.

Conclusion:

The systemic associations of RAOs in the Indian population were distinctly different from those reported in the Western population. Hyperhomocysteinemia was the commonest association found. Whereas associations reported in the Western population such as cardiac abnormalities, coagulation disorders, hemoglobinopathies and oral contraceptive use were uncommon.

Acute retinal arterial occlusive disorders

The initial section deals with basic sciences; among the various topics briefly discussed are the anatomical features of ophthalmic, central retinal and cilioretinal arteries which may play a role in acute retinal arterial ischemic disorders. Crucial information required in the management of central retinal artery occlusion (CRAO) is the length of time the retina can survive following that. An experimental study shows that CRAO for 97min produces no detectable permanent retinal damage but there is a progressive ischemic damage thereafter, and by 4h the retina has suffered irreversible damage. In the clinical section, I discuss at length various controversies on acute retinal arterial ischemic disorders. Classification of acute retinal arterial ischemic disorders: These are of 4 types: CRAO, branch retinal artery occlusion (BRAO), cotton wool spots and amaurosis fugax. Both CRAO and BRAO further comprise multiple clinical entities. Contrary to the universal belief, pathogenetically, clinically and for management, CRAO is not one clinical entity but 4 distinct clinical entities - non-arteritic CRAO, non-arteritic CRAO with cilioretinal artery sparing, arteritic CRAO associated with giant cell arteritis (GCA) and transient non-arteritic CRAO. Similarly, BRAO comprises permanent BRAO, transient BRAO and cilioretinal artery occlusion (CLRAO), and the latter further consists of 3 distinct clinical entities - non-arteritic CLRAO alone, non-arteritic CLRAO associated with central retinal vein occlusion and arteritic CLRAO associated with GCA. Understanding these classifications is essential to comprehend fully various aspects of these disorders. Central retinal artery occlusion: The pathogeneses, clinical features and management of the various types of CRAO are discussed in detail. Contrary to the prevalent belief, spontaneous improvement in both visual acuity and visual fields does occur, mainly during the first 7 days. The incidence of spontaneous visual acuity improvement during the first 7 days differs significantly (p<0.001) among the 4 types of CRAO; among them, in eyes with initial visual acuity of counting finger or worse, visual acuity improved, remained stable or deteriorated in non-arteritic CRAO in 22%, 66% and 12% respectively; in non-arteritic CRAO with cilioretinal artery sparing in 67%, 33% and none respectively; and in transient non-arteritic CRAO in 82%, 18% and none respectively. Arteritic CRAO shows no change. Recent studies have shown that administration of local intra-arterial thrombolytic agent not only has no beneficial effect but also can be harmful. Prevalent multiple misconceptions on CRAO are discussed. Branch retinal artery occlusion: Pathogeneses, clinical features and management of various types of BRAO are discussed at length. The natural history of visual acuity outcome shows a final visual acuity of 20/40 or better in 89% of permanent BRAO cases, 100% of transient BRAO and 100% of non-arteritic CLRAO alone. Cotton wools spots: These are common, non-specific acute focal retinal ischemic lesions, seen in many retinopathies. Their pathogenesis and clinical features are discussed in detail. Amaurosis fugax: Its pathogenesis, clinical features and management are described.