• Be Prepared to Act on Acute Retinal Ischemia

    What should comprehensive ophthalmologists do if they suspect or see an acute retinal or ophthalmic artery occlusion? How urgent is the referral? These important questions were answered by Valérie Biousse, MD, during the 2021 William F. Hoyt Lecture, “Acute Retinal Ischemia: Time for Action!”

    Dr. Biousse’s opening words were, “You know what I’m going to talk about. What’s the matter with you? Just do it!” This provoked some laughter and knowing nods from the audience and panelists. She then outlined the steps for confronting this ophthalmic emergency, which has potentially devastating consequences for vision and can be associated with subsequent cerebrovascular events.     

    A simple formula: Make the correct diagnosis and send the patient to the stroke center. Appropriate triage and rapid diagnosis of patients with acute monocular visual loss are critical components of acute stroke care. Dr. Biousse emphasized that when specialists are not available onsite, the use of a nonmydriatic fundus camera enables immediate diagnosis of acute central retinal artery occlusion (CRAO). One of her key messages was that having access to specialized stroke centers improves outcomes and reduces costs. Dr. Biousse strongly advised against doing the workup yourself. She said: “Don’t pretend that you can do it.”

    What is the time frame for treatment with IV tPA? Four-and-a-half hours is the window of time for treatment with tissue plasminogen activator (tPA). The patient must get to a stroke center immediately for thrombolysis. “You do not want the patient to have a stroke in your office,” said Dr. Biousse.

    Retina and brain: same mechanisms of harm. The retina and brain share the same vascular territory (anterior circulation). Transient monocular visual loss of vascular, CRAO, branch retinal artery occlusion, and ophthalmic artery occlusion all have the same pathogenesis as a thrombotic stroke causing cerebral ischemia.

    Immediate management advised. In the past, treatment was delayed for acute retinal ischemia because it was considered to be “not a bad stroke,” unlike that caused by carotid artery disease. Dr. Biousse said that changed with the Academy’s Retinal and Ophthalmic Artery Occlusions Preferred Practice Pattern guidelines in 2016 and 2019, stating that a “stroke in the eye is just as urgent as a stroke in the brain.” This year’s American Heart Association statement in the journal Stroke provided a treatment framework for  CRAO1.

    New recommendations for care. The major steps include:

    • Make the correct diagnosis.
    • Send the patient to an emergency department with a stroke center certified by the AMA. Dr. Biousse said, “Tell the patient to say: ‘I have had a stroke in the eye.’” Within 24 hours, the patient should be tested and evaluated by a neurologist to prevent a secondary stroke. Dr. Biousse strongly advised that “there is no reason to wait two weeks” because the longer the delay, the greater the risk of stroke.
    • Neurological follow-up includes:
      • Magnetic resonance imaging of the brain within 24 to 48 hours of visual loss.
      • Determination of the cause to mitigate risk of a major stroke.
      • Evaluation of the vascular risk.
      • Treatment for secondary prevention. This may include aspirin, blood pressure control, statins, and urgent treatment of the underlying cause. Patient education is also important to help reduce risk of subsequent cardiovascular and cerebrovascular events.
    • Establish a network with stroke centers and a stroke neurologist, as well as a workflow, to be prepared to initiate action when a patient presents with acute retinal ischemia. Dr. Biousse said, “This is easy. Know the nearest certified stroke center and have this contact information in your office.”

    Dr. Biousse ended her talk this way: “The 2010s showed us that time is brain, while the 2020s will show us that time is eye.”—Kathleen E. Erickson, MLIS

    1 MacGrory B et al. Stroke. 2021;52(6):e282-e294

    Financial disclosures: Dr. Biousse: No relevant disclosures