Photo credit: CC0 Public Domain
While most people think of strokes that affect the brain, they can also affect the eye. Central retinal artery occlusion (CRAO) is a rare form of acute ischemic stroke that occurs when blood flow to the main artery of the eye is blocked. It usually causes painless, immediate vision loss in the affected eye, with less than 20% of people regaining functional vision in that eye.
Today the American Heart Association published a new scientific opinion in Stroke, a journal of the American Heart Association, entitled “Management of Central Retinal Artery Occlusion.” The American Association of Neurological Surgeons / Congress of Neurosurgeons of the Department of Cerebrovascular Disease endorses the educational benefit of the scientific opinion and was approved by the North American Neuro-Ophthalmology Society, the Secretariat of the American Academy of Ophthalmology Quality of Care, and the American Academy of Optometry.
“Central retinal artery occlusion is a cardiovascular problem disguised as an eye problem. It is less common than a stroke that affects the brain, but is a critical sign of disease and requires immediate medical attention,” said Brian C. Mac, Chairman of the Statement drafting committee Grory, MBBCh., BAO, MRCP, Assistant Professor of Neurology and Personnel Neurologist at the Duke Comprehensive Stroke Center at the Duke University School of Medicine in Durham, North Carolina. “Unfortunately, a CRAO is a red flag for other vascular problems, so ongoing follow-up is critical to preventing a future stroke or heart attack.”
In a comprehensive review of world literature, committee members from the fields of neurology, ophthalmology, cardiology, interventional neuroradiology, neurosurgery and vitreoretinal surgery summarized the state of the art under these conditions. They found evidence that this type of stroke could be caused by problems with the carotid arteries, the blood vessels in the neck. However, there is also evidence that CRAOs can be caused by heart problems such as atrial fibrillation, which is the most common irregular heart rhythm. The risk of CRAO increases with age and in the presence of cardiovascular risk factors such as high blood pressure, hyperlipidemia, type 2 diabetes, smoking, and obesity.
The new scientific opinion notes that the lack of extensive clinical studies on CRAOs creates uncertainty within the medical community about exactly what causes them or how best to treat them. As a result, there is great variability in methods of diagnosis and treatment. Most worrying, according to Mac Grory, is that many doctors may not recognize CRAO as a form of stroke, resulting in patients receiving late tests and treatment, often in the ambulance rather than the emergency room.
“We know that acute CRAO is a medical emergency that requires early detection and triage for emergency medical treatment,” said Mac Grory. “There is a tight window of time for effective treatment for CRAO and a high rate of serious illness. If a person is diagnosed in a doctor’s office or other outpatient department, they should be immediately sent to a hospital emergency room for further evaluation and treatment.”
Current literature suggests that treatment with intravenous tissue plasminogen activator (tPA), a “clot buster” also used to treat stroke, may be effective. However, TPA must be administered within 4.5 hours of the first sign of symptoms for the most effective and safest effect.
The writing committee also noted that emerging treatments like hyperbaric oxygen and intra-arterial alteplase show promise but require further investigation. Other potential treatments that require further research and evaluation include novel thrombolytics to break down clots and novel neuroprotectants (substances that can maintain brain function and structure) for use in conjunction with other therapies to restore blood flow to the blocked artery.
Because of the potential for future strokes or even heart attacks, patients should urgently be screened for and treated for vascular risk factors. The writing committee notes that the complexities of diagnosing and treating CRAOs require a team of specialists to work together. Secondary prevention (including monitoring for complications) must be a collaboration between neurologists, ophthalmologists, cardiologists and primary care clinicians. The change in risk factor includes lifestyle and pharmacological interventions.
Outlined steps to reduce the risk of stroke during heart surgery
Brian Mac Grory et al., Management of Central Retinal Artery Occlusion: A Scientific Commentary from the American Heart Association, Stroke (2021). DOI: 10.1161 / STR.0000000000000366 Provided by the American Heart Association
Quote: A stroke that affects the eye requires immediate treatment and may indicate future vascular events (2021 March 8) posted on March 8, 2021 from https://medicalxpress.com/news/2021-03-affecting -eye-requires-treatment-future.html
This document is subject to copyright. Except for fair trade for the purpose of private study or research, no part may be reproduced without written permission. The content is provided for informational purposes only.