Acute Central Retinal Artery Occlusion Treated with Intravenous Recombinant Tissue Plasminogen Activator

Central retinal artery occlusion as a neuro-ophthalmological emergency: the need to raise public awareness

BACKGROUND AND PURPOSE

Central retinal artery occlusion (CRAO) is a neuro-ophthalmological emergency necessitating adequate and comprehensive diagnosis. Its optimal management and treatment, however, are still under debate. This study aimed at identifying respective areas for improvement.

METHODS

We retrospectively analysed the medical records of patients with CRAO treated in our stroke unit between January 2016 and August 2020.

RESULTS

During the observational period, 101 patients with CRAO were admitted. We observed an increase in the rate of patients primarily admitted to the stroke unit from 52.2% to 97.4%. In addition, the thrombolysis rate - with thrombolysis performed on an individual basis - rose from 0% to 14.1%, coinciding with the implementation of an in-hospital management guideline. Almost 60% of all patients presented outside of the 4.5-h time window for thrombolysis; by far the most common reason not to deliver intravenous thrombolysis in our cohort was a prehospital delay to presentation (58.8%), with 44.4% of patients having consulted a private-practice ophthalmologist first. A total of 25 (32.5%) of 77 patients who underwent magnetic resonance imaging (MRI) had accompanying acute ischaemic stroke lesions on diffusion-weighted MRI of the brain. A possible aetiology of CRAO was identified in 41.4% of patients.

DISCUSSION

Public awareness of sudden unilateral visual loss as a presenting sign for stroke should be raised, increasing the chances for timely recognition in a hospital with ophthalmological expertise and a stroke centre. This is essential for ongoing and future prospective trials on this subject.

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.

Use of recombinant tissue plasminogen activator for treatment of recalcitrant anterior uveitis: A case series

Management of inflammation after surgery for recalcitrant anterior uveitis is challenging. Herein, we report successful treatment using intracameral injection of recombinant tissue plasminogen activator (rtPA) in two patients with recalcitrant anterior uveitis, due to infective uveitis and Vogt-Koyanagi-Harada disease, respectively. A 40-year-old woman presented with bilateral redness and vision reduction that had persisted 2 weeks. She also had bilateral anterior uveitis, vasculitis, retinitis, and optic disc swelling. Serology was positive for Bartonella henselae and Toxoplasma gondii. She was treated using long-term systemic corticosteroids and appropriate antibiotics. Our second case; a healthy 30-year-old man with bilateral eye redness and reduced vision without pain, and associated with headache and tinnitus for 1 weeks. He showed bilateral granulomatous inflammation with vitritis, choroiditis, retinitis, and hyperemic optic disc. The patient was diagnosed with Vogt-Koyanagi-Harada disease and treated with systemic corticosteroids. Both patients developed secondary cataracts and glaucoma that necessitated surgical intervention. Persistent chronic inflammation led to the formation of a thick fibrin membrane anterior to the intraocular lens (IOL) after phacoemulsification surgery with IOL implantation. This membrane was removed surgically, and intracameral injection of rtPA (25 μg) was carried out. The persistent inflammation had resolved and visual acuity had significantly improved within 1 week of intracameral rtPA injection. There were no reported ocular or systemic side effects. Intracameral rtPA is beneficial in patients with recalcitrant anterior uveitis who have undergone intraocular surgery. In most cases, surgical intervention improves the patients' vision. Intracameral rtPA should be considered in cases of persistent inflammation of varying etiology.

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.

Observation on therapeutic efficacy of rt-PA intravenous thrombolysis combined with compound anisodine injection on central retinal artery occlusion

The aim of the present study was to observe the clinical efficacy and safety of recombinant tissue plasminogen activator (rt-PA) combined with compound anisodine in treating central retinal artery occlusion (CRAO). Forty-eight patients diagnosed with CRAO were randomly divided into a treatment group (24 cases) and a control group (24 cases). For the control group, nitroglycerin, 654-2, methazolamide, puerarin and compound anisodine were used for the treatment, along with oxygen, massage and other conventional treatments. Besides conventional therapy, the treatment group was also given intravenous rt-PA thrombolysis. Visual acuity, fundus oculi, visual field changes were taken as indicators for efficacy evaluation. It was found that the total effective rate of the control group was 70.83%, while that for the treatment group was 91.67%, and the comparative difference between the two groups was of statistical significance (p<0.05). The visual field defect of the control group after treatment was approximately 74.26±12.91%, and the visual field defect of the treatment group after treatment approximately 35.08±16.33%; thus, the comparative difference was statistically significant (p<0.01). The comparative difference of the original contents of fibrous protein in blood in the treatment group before and after treatment was statistically significant (p<0.01). In conclusion, the result show that intravenous thrombolysis with rt-PA combined with compound anisodine is safe and effective in treating CRAO, which can significantly improve the prognosis of patients.