It is well known that strokes affect brain function, however, many people are unaware that they can also have lasting effects on the eyes. A rare type of stroke referred to as central retinal artery occlusion (CRAO) is caused by a lack of blood flow to the eye’s central artery. The pain is usually acute, however, vision is immediately lost in the affected eye.
According to research, less than 20% of people affected by CRAO regain their vision. The recent study suggests that CRAO occurs as a result of cardiovascular issues.
“Central retinal artery occlusion is a cardiovascular problem disguised as an eye problem. It is less common than a stroke affecting the brain but is a critical sign of ill health and requires immediate medical attention. Unfortunately, a CRAO is a warning sign of other vascular issues, so ongoing follow-up is critical to prevent a future stroke or heart attack,” says Brian C. Mac Grory, an assistant professor of neurology and staff neurologist at the Duke Comprehensive Stroke Center at Duke University School of Medicine.
Analysis of this condition by specialists indicates that issues within the carotid arteries and the heart can cause a CRAO. For example, atrial fibrillation, a form of irregular heartbeat, may be linked to CRAO. Those with an increased risk for cardiovascular disease also have an increased risk of developing a CRAO. These people include Type 2 diabetics, those with high blood pressure and/or large amounts of lipids or fats in the blood, those who smoke, and those that are considered obese.
Due to the lack of clinical trials, the exact cause is unknown, which leads to varying treatment methods, as well as varying methods in diagnosis. Many patients, unfortunately, receive outpatient treatment because most practitioners diagnose CRAO as an eye condition rather than as the result of an ischemic stroke.
“We know acute CRAO is a medical emergency requiring early recognition and triage to emergency medical treatment. There is a narrow time window for effective treatment of CRAO and a high rate of serious related illness. So, if a person is diagnosed in a doctor’s office or an outpatient clinic, they should be immediately sent to a hospital emergency department for further evaluation and treatment,” says Mac Grory.
Current treatment includes intravenous tissue plasminogen activator (tPA) to break up the clot, however, it must be given to the patient no later than 4.5 hours prior to the onset of symptoms. Treatments such as receiving oxygen from a hyperbaric chamber and intra-arterial alteplase are currently being studied for their effectiveness. Another clot-breaking treatment involving thrombolytics has proven to help increase blood flow in blockages with the help of neuroprotectants which preserve the structure and function of the brain.
Specialists suggest that CRAO patients be screened immediately for vascular damage and any risk factors associated with cardiovascular disease. Neurologists, cardiologists, and ophthalmologists collectively can help patients prevent future strokes. Changes to a person’s lifestyle and certain medications can help treat CRAO.
This study is published in Stroke, an American Heart Association journal.