By Matthew E. Fink, MD

Louis and Gertrude Feil Professor and Chair, Department of Neurology, Associate Dean for Clinical Affairs, New York Presbyterian/Weill Cornell Medical College

Dr. Fink reports no financial relationships relevant to this field of study.

SOURCE: MacGrory B, Nackenoff A, Poli S, et al. Intravenous fibrinolysis for central retinal artery occlusion. A cohort study and updated patient-level meta-analysis. Stroke 2020;51:2018-2025.

Central retinal artery occlusion (CRAO) is a serious threat to vision caused by interruption of the blood supply to the retina and leading to sudden, painless loss of vision in one eye. For 30 years there have been anecdotal reports and small case series suggesting that intravenous thrombolysis might be beneficial in this disorder, but none of the stroke treatment guidelines have incorporated thrombolysis as definitive treatment for this disorder. At the present time, there is no effective treatment that has been proven to salvage vision in patients with CRAO.

The investigators in this study enrolled consecutive patients with acute CRAO within 48 hours of symptom onset who had a visual acuity < 20/200. This was an open-label trial, and there was no randomization. Patients were treated per the local treating physician. The primary outcomes were safety and functional visual recovery. Rates of recovery were compared for those treated with alteplase within 4.5 hours of symptom onset to those who did not receive alteplase, including a comparison with untreated patients who presented within the window for potential thrombolytic treatment, or 4.5 hours from onset of symptoms. Cases were collected from several different medical centers, and the protocols for treatment varied considerably from different centers.

The principal investigators enrolled 112 patients into the prospective cohort, of whom 25 (22.3%) were treated with intravenous alteplase. One patient had an asymptomatic brain hemorrhage after alteplase treatment. Forty-four percent of patients treated with alteplase had recovery of visual acuity if treated within 4.5 hours of symptom onset compared to 13.1% of those who were not treated with alteplase (P = 0.003) and 11.6% of those who arrived within four hours of symptom onset but did not receive alteplase. In a meta-analysis of 238 patients from multiple centers, including 67 patients treated with alteplase within 4.5 hours of symptom onset, the recovery rate for vision was 37.3%. Those who were not treated with intravenous alteplase had a 17.7% rate of recovery.

The authors concluded that administration of intravenous alteplase within 4.5 hours of onset of symptoms results in a much higher likelihood of a favorable visual outcome for patients who have acute CRAO. A randomized, prospective, placebo-controlled clinical trial is strongly recommended to determine definitively if this treatment is beneficial.