Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) are more prominent in retinal artery occlusion (RAO) compared to retinal vein occlusion (RVO).

AIM: To evaluate the association between the value of neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), monocyte to high-density lipoprotein ratio (MHR) and the development of retinal artery occlusion (RAO) and retinal vein occlusion (RVO). METHODS: This retrospective study assessed 41 RAO, 50 RVO and 50 control (age and gender matched senile cataract) participants. The NLR, PLR and MHR parameters of patients' peripheral blood were analyzed. A receiver operating characteristics (ROC) curve analysis and the best cutoff value were used to specify the predictive value of NLR, PLR and MHR in RAO and RVO. RESULTS: The NLR, PLR and MHR were significantly higher in RAO group compared to the control group (p<0.001, p<0.001 and p = 0.008; respectively). The NLR, PLR and MHR were also significantly higher in the RVO group compared to the control group (p<0.001, p = 0.001 and p = 0.012, respectively). The NLR and PLR were significantly higher in the RAO group compared to the RVO group (p<0.001 and p = 0.022, respectively). The optimal cut-off value of NLR to predict RAO was >2.99, with 90.2% sensitivity and 100% specificity. The PLR to predict RAO was > 145.52, with 75.6% sensitivity and 80.0% specificity. CONCLUSION: Higher NLR, PLR and MHR are related to the occurrence of RAO and RVO. NLR and PLR are more prominent in RAO compared to RVO.

Retinal diffusion restrictions in acute branch retinal arteriolar occlusion.

This study sought to investigate the occurrence of retinal diffusion restrictions (RDR) in branch retinal arteriolar occlusion (BRAO) using standard brain diffusion-weighted imaging (DWI). Two radiologists assessed DWI MRI scans of BRAO patients for RDR in a retrospective cohort study. Inter- and intrarater reliability were calculated using Kappa statistics. Detection rates of RDR were compared among MRI scans with varying field strength, sequence type and onset-to-DWI time intervals. 85 BRAO patients (63.1 ± 16.5 years) and 89 DWI scans were evaluated. Overall sensitivity of RDR in BRAO was 46.1% with visually correlating low ADC signal in 56.1% of cases. Localization of RDR matched distribution of fundoscopic retinal edema in 85% of patients. Inter- and intra-rater agreement for RDR in BRAO was κinter = 0.64 (95% CI 0.48-0.80) and κintra = 0.87 (95% CI 0.76-0.96), respectively. RDR detection rate tended to be higher for 3T, when compared to 1.5T MRI scans (53.7% vs. 34.3%%; p = 0.07). RDR were identified within 24 h up to 2 weeks after onset of visual impairment. RDR in BRAO can be observed by means of standard stroke DWI in a substantial proportion of cases, although sensitivity and interrater reliability were lower than previously reported for complete central retinal artery occlusion.

Acute Central Retinal Artery Occlusion Seen within 24 Hours at a Tertiary Institution.

OBJECTIVE: Acute central retinal artery occlusion (CRAO) is an emergency with poor visual outcome. Intravenous thrombolysis within 4.5 h of vision loss is safe and may improve vision, but is rarely administered because of frequent delays in presentation. We describe a subgroup of CRAO patients presenting within 24 h of vision loss to a tertiary care center affiliated with a comprehensive stroke center. MATERIALS AND METHODS: Retrospective review of 181 consecutive CRAO patients seen at our institution from 2010 to 2020. RESULTS: Out of 181 CRAO patients, 62 (34%) presented within 24 h of vision loss and tended to live closer to the hospital. These patients were more likely to be admitted to the hospital and receive comprehensive stroke work-up compared to patients who presented after 24 h of vision loss. Patients presenting after 24 h did not necessarily receive prior appropriate work-up at outside institutions. Conservative treatments for CRAO were administered to 20/181 patients, and only 3 patients received intravenous thrombolysis. CONCLUSIONS: Patients with CRAO do not present to the emergency department fast enough and diagnosis of CRAO is often delayed. Despite having a protocol in place, only 3/181 patients received IV thrombolysis, emphasizing the difficulty in administering very acute treatments for CRAO. Public education regarding CRAO is necessary to improve presentation times, management, and visual outcomes. Hospitals need to develop accelerated diagnostic pathway protocols for patients with acute vision loss so that CRAO patients may be diagnosed and be considered for potential acute treatments as quickly as possible.

THE NATIONWIDE INCIDENCE OF RETINAL ARTERY OCCLUSION FOLLOWING DIALYSIS AS A RESULT OF END-STAGE RENAL DISEASE: 2004 Through 2013.

PURPOSE: To examine the incidence and risk of retinal artery occlusion (RAO) in patients who have undergone dialysis in Korea. METHODS: A nationwide, population-based study using South Korean national health insurance data from 2004 to 2013 was used for analysis. All patients who began dialysis between 2004 and 2013 and the same number of control subjects were selected via propensity score matching. The incidence of RAO in the dialysis and control cohorts was calculated for 2004 to 2013 using washout data from 2003. The multivariable Cox proportional hazards model was used to evaluate the risk of developing RAO in dialysis patients. Cumulative RAO incidence curves were generated using the Kaplan-Meier method. Whether dialysis modalities influenced the incidence of RAO was also evaluated. RESULTS: Seventy-six thousand seven hundred and eighty-two end-stage renal disease patients on dialysis were included in the dialysis cohort, and 76,782 individuals were included in the control cohort. During the study period, 293 patients in the dialysis cohort and 99 patients in the control cohort developed RAO. The person-years incidence of RAO was significantly higher in the dialysis cohort than in the control cohort (dialysis = 1.1/1,000 person-years; control = 0.3/1,000 person-years; P < 0.001). The incidence of RAO was not significantly different between the two methods of dialysis (hemodialysis vs. peritoneal dialysis; P = 0.25, log-rank test). CONCLUSION: The current study provided epidemiological evidence that undergoing dialysis for end-stage renal disease was associated with an increased risk of developing RAO. The incidence of RAO rapidly increased as the duration of dialysis increased. These results strengthen the significant role of the renal function in retinal vascular disease.

Structural and Functional Imaging of the Retina in Central Retinal Artery Occlusion - Current Approaches and Future Directions.

Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke which affects the retina. Intravenous thrombolysis is emerging as a compelling therapeutic approach. However, it is not known which patients may benefit from this therapy because there are no imaging modalities that adequately distinguish viable retina from irreversibly infarcted retina. The inner retina receives arterial supply from the central retinal artery and there is robust collateralization between this circulation and the outer retinal circulation, provided by the posterior ciliary circulation. Fundus photography can show canonical changes associated with CRAO including a cherry-red spot, arteriolar boxcarring and retinal pallor. Fluorescein angiography provides 2-dimensional imaging of the retinal circulation and can distinguish a complete from a partial CRAO as well as central versus peripheral retinal non-perfusion. Transorbital ultrasonography may assay flow through the central retinal artery and is useful in the exclusion of other orbital pathology that can mimic CRAO. Optical coherence tomography provides structural information on the different layers of the retina and exploratory work has described its utility in determining the time since onset of ischemia. Two experimental techniques are discussed. 1) Retinal functional imaging permits generation of capillary perfusion maps and can assay retinal oxygenation and blood flow velocity. 2) Photoacoustic imaging combines the principles of optical excitation and ultrasonic detection and - in animal studies - has been used to determine the retinal oxygen metabolic rate. Future techniques to determine retinal viability in clinical practice will require rapid, easily used, and reproducible methods that can be deployed in the emergency setting.

Diabetic and Retinal Vascular Eye Disease.

The retinal vasculature is the only neurovascular system directly visible to the human eye, easily evaluated by fundoscopy and many imaging modalities. This window allows physicians to diagnose and treat retinal pathologies and detect systemic diseases including diabetes, hypertension, hypercoagulable/hyperviscosity syndromes, and vasculitis. Diabetic retinopathy is the most common retinal vascular disease, followed by retinal vein and artery occlusion. Patients with these conditions require medical optimization to prevent further damage to the eyes and to the other organs. Both the internists and medical subspecialists play a crucial role in the prevention, detection, evaluation, and management of vision-threatening retinal vascular diseases.

Central retinal artery occlusion after Descemet membrane reposition by intracameral air: A case report.

PURPOSE: To report a case of central retinal artery occlusion after Descemet membrane reposition by intracameral air. METHODS: An otherwise healthy 60-year-old woman presented with white mature cataract in her left eye. Ocular exam of both eyes was within normal limits. After an uneventful topical phacoemulsification, a moderate-grade striate keratopathy and non-planar Descemet membrane detachment was noted on first postoperative day, which was confirmed on anterior segment optical coherence tomography. The Descemet membrane was repositioned within 24 h of cataract extraction by intracameral air tamponade (pneumatic descematopexy) under topical anesthesia, and partial air release was done after 2 h. The patient was evaluated for decreased immediate postoperative vision of perception of light. RESULTS: After pneumatic descematopexy, the stromal edema relatively cleared. The intraocular pressure before releasing the intracameral air was 38 mmHg and antiglaucoma medication was started. Dilated fundus exam showed retinal pallor and a cherry-red spot over the macula. A diagnosis of central retinal artery occlusion was confirmed, and thorough systemic workup was done. Systemic investigations were within normal limits. The patient was managed conservatively, but the final visual acuity remained at 1/60. CONCLUSION: Central retinal artery occlusion is not a reported complication after pneumatic descematopexy for Descemet membrane detachment management. The possible mechanism could be sudden increase in intraocular pressure due to pupil block by air, and thus, ocular surgeries with use of intracameral air for prolonged duration warrants close monitoring of intraocular pressure and its subsequent management.

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.

Risk of Retinal Artery Occlusion in Patients with Migraine.

PURPOSE: We sought to determine if migraine is associated with increased risk of retinal artery occlusion (RAO). DESIGN: Retrospective cohort study. METHODS: We reviewed a large insurance claims database for patients with migraine and matched control subjects without migraine between 2007 and 2016. Cox proportional hazard regression models were used to investigate the association between migraine and risk of all RAO, central RAO (CRAO), branch RAO (BRAO), and "other" RAO, which includes transient and partial RAO. Primary outcome measures included the incidence of all RAO, including CRAO, BRAO, and other RAO, after first migraine diagnosis. RESULT: There were 418,965 patients with migraine who met the study criteria and were included in the analysis with the appropriate matched control subjects. Among the 418,965 patients with migraine, 1060 (0.25%) were subsequently diagnosed with RAO, whereas only 335 (0.08%) of the patients without migraine were diagnosed with RAO. The hazard ratio (HR) for incident all RAO in patients with migraine compared with those without migraine was 3.48 (95% confidence interval [CI] 3.07-3.94; P < .0001). This association was consistent across all types of RAO, including CRAO (HR 1.62 [95% CI 1.15-2.28]; P = .004), BRAO (HR 2.09 [95% CI 1.60-2.72]; P < .001), and other types of RAO (HR 4.61 [95% CI 3.94-5.38]; P < .001). Patients with migraine with aura had a higher risk for incident RAO compared with those with migraine without aura (HR 1.58 [95% CI 1.40-1.79]; P < .001). This association was consistent for BRAO (HR 1.43 [95% CI 1.04-1.97]; P < .03) and other types of RAO (HR 1.67 [95% CI 1.45-1.91]; P < .001) but was not statistically significant for CRAO (HR 1.18 [95% CI 0.75-1.87]; P = .475). Significant risk factors for this association included increased age, male sex, acute coronary syndrome, valvular disease, carotid disease, hyperlipidemia, hypertension, retinal vasculitis or inflammation, and systemic lupus erythematosus. CONCLUSIONS: Migraine is associated with increased risk of all types of RAO and migraine with aura is associated with increased risk of RAO compared with migraine without aura.

Retinal vascular occlusions.

Acute retinal vascular occlusions are common causes of visual impairment. Although both retinal artery occlusions and retinal vein occlusions are associated with increased age and cardiovascular risk factors, their pathophysiology, systemic implications, and management differ substantially. Acute management of retinal artery occlusions involves a multidisciplinary approach including neurologists with stroke expertise, whereas treatment of retinal vein occlusions is provided by ophthalmologists. Optimisation of systemic risk factors by patients' primary care providers is an important component of the management of these two disorders.

Bilateral, vertical supranuclear gaze palsy following unilateral midbrain infarct.

A 60-year-old man recently admitted for bipedal oedema, endocarditis and a persistently positive COVID-19 swab with a history of anticoagulation on rivaroxaban for atrial fibrillation, transitional cell carcinoma, cerebral amyloid angiopathy, diabetes and hypertension presented with sudden onset diplopia and vertical gaze palsy. Vestibulo-ocular reflex was preserved. Simultaneously, he developed a scotoma and sudden visual loss, and was found to have a right branch retinal artery occlusion. MRI head demonstrated a unilateral midbrain infarct. This case demonstrates a rare unilateral cause of bilateral supranuclear palsy which spares the posterior commisure. The case also raises a question about the contribution of COVID-19 to the procoagulant status of the patient which already includes atrial fibrillation and endocarditis, and presents a complex treatment dilemma regarding anticoagulation.

Eye Emergencies.

Central retinal artery occlusions, chemical injuries, mechanical globe injuries, and retinal detachments are eye emergencies that can result in permanent vision loss if not treated urgently. Family physicians should be able to recognize the signs and symptoms of each condition and be able to perform a basic eye examination. Patients with a central retinal artery occlusion require urgent referral for stroke evaluation and should receive therapy to lower intraocular pressure and vasodilating agents to minimize retinal ischemia. Chemical injuries require immediate irrigation of the eye to neutralize the pH of the ocular surface. A globe laceration or rupture is common in patients with a recent history of trauma from a blunt or penetrating object. Physicians should administer prophylactic oral antibiotics after a globe injury to prevent endophthalmitis. The eye should be covered with a metal shield until evaluation by an ophthalmologist. Patients with symptomatic floaters and flashing lights should be referred to an ophthalmologist for a dilated funduscopic examination to evaluate for a retinal tear or detachment.

Optical Coherence Tomography Angiography and Multifocal Electroretinogram Findings in Paracentral Acute Middle Maculopathy.

Paracentral acute middle maculopathy (PAMM) is an optical coherence tomography (OCT) finding seen in patients with retinal capillary ischemia. In this case report, we present a case of PAMM after a transient central retinal artery occlusion and the multifocal electroretinogram (mfERG) and other multimodal imaging findings. Clinical examination, OCT angiography, OCT en face, fluorescein angiography, and visual fields were performed at the baseline and follow-up examinations. As a result, we identified in this PAMM case evidence of hypoperfusion in both the choriocapillaris as well as the deep capillary plexus. To the best of our knowledge, the involvement of choriocapillaris has not been reported previously in the literature. Moreover, we concluded that mfERG constitutes a useful investigation in PAMM and this is the first mfERG findings to be presented for a PAMM case specifically.

Normal to supernormal 30-Hz flicker ERGs predict visual function and prognosis in central retinal artery occlusion.

PURPOSE: To determine whether normal to supernormal 30-Hz flicker ERGs are associated with visual function and prognosis in patients with central retinal artery occlusion (CRAO). METHODS: A total of 133 patients diagnosed with unilateral acute non-arteritic CRAO by examination with electroretinography (ERG) were examined. Thirty-hertz flicker ERG amplitudes were analyzed according to the severity of CRAO, and their correlation with visual function and prognosis was assessed. All patients were categorized into one of three groups according to the flicker ERG amplitude ratios between affected and fellow eyes: ≥ 110%, supernormal; 90-110%, normal; and < 90%, subnormal. RESULTS: Thirty-hertz flicker ERG parameters differed significantly according to the severity of retinal ischemia, i.e., between incomplete versus complete CRAO: mean amplitude (55.89 ± 24.38 > 45.41 ± 23.47 µV, P = 0.029), amplitude ratio (76.1 ± 23.1% > 58.7 ± 25.7%, P < 0.001), and proportion of normal to supernormal flicker ERGs (30.5% > 12.4%, P < .001). One-month and final follow-up visual function and prognosis were better in the normal to supernormal flicker ERGs: 1 month BCVA (1.55 ± 0.65 > 2.05 ± 0.61 logMAR, P < .001), final BCVA (1.32 ± 0.79 > 1.97 ± 0.68 logMAR, P < .001), 1-month VA improvement (- 0.50 ± 0.47 > - 0.10 ± 0.29 logMAR, P < .001), and final VA improvement (- 0.74 ± 0.61 > - 0.18 ± 0.37 logMAR, P < .001). CONCLUSIONS: Normal to supernormal 30-Hz flicker ERG changes in eyes with CRAO are associated with the milder severity of retinal ischemia and showed better visual function and outcome than the subnormal ERG group.