Eye Stroke

Have you ever heard of an eye stroke? This surprising condition affects thousands yearly, causing sudden vision problems and potential long-term damage to eyesight. Eye strokes happen when blood flow to the eye is disrupted, leading to a range of symptoms that can be both alarming and confusing. Understanding eye stroke's early signs and causes is crucial for timely intervention and treatment. 

This article explores the world of eye strokes, shedding light on their types, symptoms, and eye stroke reasons. 

What is an Eye Stroke? 

An eye stroke, medically known as retinal artery occlusion, develops when blood flow to the retina is blocked. This occlusion is often due to a blood clot or narrowing of the eye's blood vessels. The retina, a crucial tissue at the back of the eye, relies on oxygen-rich blood to function correctly and send visual signals to the brain. When this blood supply is interrupted, it can lead to rapid and severe vision loss in the affected eye. 

Types of Eye Strokes 

Eye strokes can be classified into several types based on the location of the blockage. 

• Central Retinal Artery Occlusion (CRAO): CRAO is the most common eye stroke type. This occurs when the main artery supplying blood to the retina becomes blocked and causes sudden and severe vision loss in the affected eye. 
• Branch Retinal Artery Occlusion (BRAO): This type develops when a smaller artery in the eye gets blocked, resulting in partial vision loss. 
• Retinal Vein Occlusion (RVO): This eye stroke affects the veins rather than the arteries. It can be further divided into: 
  • Central Retinal Vein Occlusion (CRVO) 
  • Branch Retinal Vein Occlusion (BRVO) 

These conditions can lead to complications such as macular oedema and retinal ischemia, potentially causing long-term vision problems. 

Symptoms of Eye Stroke 

Eye stroke symptoms can develop gradually or suddenly, affecting one eye. The severity depends on the location & extent of the blockage. The following are common signs and symptoms of eye stroke: 

• Eye floaters appear as small grey spots in your vision 
• Blurred vision that may worsen on one side or throughout the visual field 
• Vision loss can range from subtle to severe, occurring gradually or abruptly. 
• In some cases, particularly with Central Retinal Vein Occlusion (CRVO), individuals might experience pressure or discomfort in the affected eye. The retina may appear red or have blood spots. 
• Central Retinal Artery Occlusion (CRAO) often causes partial or complete central vision loss, resembling a black curtain descending over the eye. 

These symptoms require emergency management to prevent permanent vision loss. 

Eye Stroke Causes 

Eye strokes occur when retinal blood flow is interrupted. This disruption often results from a blood clot or fatty deposits blocking the retinal arteries. Atherosclerosis, the hardening of arteries, increases the risk of such blockages. Clots may originate in other body parts, such as the heart or carotid artery, and travel to the eye. High blood pressure, diabetes, and high cholesterol are significant risk factors that contribute to eye strokes. Sometimes, the exact cause remains unclear, but these underlying health issues can play a key role in the development of this serious eye condition. 

Risk Factors 

Several factors increase the likelihood of experiencing an eye stroke, such as: 

• Age plays a major role, with individuals above 60 facing a higher risk. 
• Men are more susceptible than women. 
• Health conditions such as hypertension or high blood pressure, high cholesterol, and diabetes contribute substantially to the risk. 
• A history of heart problems, including previous heart attacks, chest pain, or coronary heart disease, raises the chances of an eye stroke. 
• A personal or family history of stroke or glaucoma increases vulnerability. 
• Lifestyle factors like smoking & lack of physical activity also contribute. 

Complications 

If left untreated, eye strokes can lead to severe complications, such as: 

• Macular oedema, or macula swelling, may cause blurred vision or vision loss. 
• Neovascularisation, the growth of abnormal blood vessels in the retina, can result in floaters and, in extreme cases, retinal detachment. 
• Neovascular glaucoma, a painful increase in eye pressure, may also develop. 
• The most severe complication is blindness, which can occur without prompt medical care. 

Eye Stroke Diagnosis 

Diagnosing an eye stroke involves a comprehensive eye exam and various imaging tests. 

• Eye Examination: An ophthalmologist will use an ophthalmoscope, a slit lamp or fundoscopy to examine the eye's structures, blockage of blood circulation, or retinal damage. 
• Fluorescein Angiography: This is a crucial diagnostic test that utilises a special dye injected into the arm to capture detailed images of retinal blood flow. 
• Optical Coherence Tomography (OCT): OCT creates cross-sectional retina images, revealing swelling or damage. 
• Blood Tests: Doctors may conduct various blood investigations to check for underlying conditions like diabetes or high cholesterol. These diagnostic procedures help identify the type and extent of eye stroke, enabling prompt treatment to prevent vision loss. 

Eye Stroke Treatment 

Prompt treatment is crucial for eye strokes to minimize retinal damage. 

• Restoration of the Blood Flow: Doctors may use various approaches to restore blood flow. These include eye massage, where the eyelid is gently pressed to dislodge clots. Patients might inhale a carbon dioxide-oxygen mixture to widen arteries and boost blood flow. 
• Paracentesis: Doctors may use this procedure to reduce eye pressure. 
• Medications: Doctors may prescribe medicines, such as clot-busting drugs or those used for glaucoma, to treat underlying conditions. 
• Oxygen Therapy: In some instances, hyperbaric oxygen therapy has shown promise. The effectiveness of these treatments often depends on how quickly they're initiated after symptom onset. 
• Long-term follow-up care is essential to manage underlying health conditions and prevent future eye strokes. 

When to See a Doctor 

Going to the hospital immediately is crucial if you experience sudden vision loss in one eye, even if it's temporary. This could indicate an eye stroke, which requires urgent treatment for the best outcomes. 

Other symptoms that warrant immediate care include: 

• Double vision- the sensation of a curtain being drawn over your vision 
• The appearance of blind spots or halos around lights. 
• A red and painful eye with blurry vision 

Prevention 

Preventing eye strokes involves managing underlying health conditions and adopting a healthy lifestyle, including: 

• Regular exercise helps maintain vascular health. 
• A balanced diet incorporating fruits, vegetables, whole grains, and lean proteins supports overall well-being. 
• Limiting table salt intake to 1,500 milligrams per day and avoiding high-cholesterol foods can reduce the risk of eye strokes. 
• Quitting smoking is crucial, as it accelerates clot formation. 
• Regular check-ups, including blood pressure and cholesterol screenings, are essential. 
• For those with diabetes, annual eye exams are recommended. 
• By addressing these factors, individuals can significantly lower their risk of experiencing an eye stroke and protect their vision. 

Conclusion 

Eye strokes significantly impact vision and overall health. Prompt recognition of symptoms and quick medical attention are crucial to prevent permanent damage. Regular eye check-ups and a vascular-healthy lifestyle are essential to safeguarding eye health. 

FAQ's 

1. Can an eye recover from an eye stroke? 

Recovery from an eye stroke is possible, especially with prompt treatment. However, complete recovery is rare. Some vision improvement may occur within the first few months after the stroke. The extent of recovery depends on the severity of the damage and the affected area of the retina. 

2. What are the signs of a stroke in your eye? 

Eye stroke symptoms include sudden vision loss or changes in one eye, floaters, blurred vision, blind spots, and sometimes pressure or discomfort. 

3. Is an eye stroke different from a regular stroke? 

Yes, an eye stroke differs from a regular stroke. An eye stroke affects blood flow to the retina, while a regular stroke impacts blood flow to the brain. 

4. Is eye stroke temporary? 

Eye strokes can cause temporary or permanent vision changes. Some people may experience temporary vision loss that improves over time, while others may have lasting effects. The outcome depends on factors such as the type of eye stroke and how quickly treatment is received. 

5. Can an eye test detect a stroke? 

While a routine eye test may not specifically detect a stroke, it can reveal signs of underlying health conditions that increase stroke risk. Comprehensive eye exams, including retinal imaging, can help identify vascular abnormalities associated with stroke risk. 

6. Is sudden blurred vision a stroke? 

Sudden blurring of vision can be a sign of an eye stroke or a brain stroke affecting the visual cortex. It may also have other causes. Any sudden vision changes should be treated as a medical emergency and evaluated immediately to rule out severe conditions like stroke. 

Dr. Neelu Agrawal

CARE Medical Team