Intravenous Thrombolytic Therapy for Acute Nonarteritic Central Retinal Artery Occlusion. A Review

Abstract

Central retinal artery occlusion (CRAO) is a form of acute ischemic stroke. It is a critical condition that often leads to severe visual loss or blindness and can be a harbinger of further cerebrovascular events. Due to the lack of scientific data, there are no effective evidence-based forms of therapy for this condition. None of the conservative therapies have proven effective. The results of some previously published studies suggest a benefit of intravenous thrombolytic therapy in the same regimen as in the treatment of ischemic stroke. This work aims to present an overview of published clinical studies focused on the use of intravenous thrombolysis for CRAO, evaluate its efficacy and safety, and propose an optimal diagnostic and therapeutic algorithm for acute management of CRAO. Summary statistics of patient data from relevant studies indicate that a significant visual acuity improvement was achieved by a total of 45 % of patients receiving alteplase within 4.5 hours of symptoms onset. The occurrence of adverse events in this time window was not significant. Intravenous thrombolytic therapy in CRAO thus appears to be effective and safe. However, we still lack data from adequate prospective randomized controlled trials to confirm this conclusion. To date, two randomized trials are being conducted. The intravenous thrombolysis administration, patient monitoring, etiologic workup, and setting of effective secondary prevention should be ensured at the centre of highly specialized cerebrovascular care. Urgent transport of the CRAO patient to the nearest centre is essential.

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

“…If the patient has had symptoms for over 4.5 h, the patient should be commenced on antiplatelet therapy and reviewed by the acute stroke unit for workup and secondary prevention" [30]. Yet another review by Janská et al concluded, "It seems that the IVT efficacy and safety can be confirmed" [31]. Okonkwo et al made a case for neuroprotective strategies in patients with CRAO, and on the subject of IVT state "...intravenous (IV) thrombolysis (IV-tPA) in CRAO though controversial, could hold some promise for a category of patients who can have treatment early and perhaps suffer from incomplete arterial occlusion" [32].…”

Nationwide Incidence and Trends in Central Retinal Arterial Occlusion Management: A 5000-Patient Analysis

“…This improvement is particularly notable for patients presenting with visual acuity of 20/40 or better. 5,[7][8][9] Critically, preventing significant vision loss has been accomplished with tPA treatment up to 12 hours after symptom onset. 1 However, it has been proposed that the clinically important time limit for inner retinal nonperfusion has been greatly overestimated since this value has mainly been determined by experimental studies that did not accurately model CRAO in nonhuman primates, 1 further adding to the uncertainty surrounding treatment for this condition.…”