A single episode of blurry vision in one eye may not seem like a health emergency to most people. It is often dismissed as eye strain or tiredness. However, experts suggest that what appears to be an innocent symptom could actually be your body's warning of a potentially life-threatening condition.
According to Dr Mangesh Udar, Consultant Neurology, Manipal Hospitals, Baner, Pune, blurred vision in one eye that clears up within a few minutes can be a sign of amaurosis fugax, a condition often described as a warning sign of a stroke. Early diagnosis and treatment could help prevent permanent vision loss or even a major stroke.
What is amaurosis fugax?
Amaurosis fugax is a temporary loss or blurring of vision in one eye caused by a brief reduction in blood flow to the retina, the light-sensitive tissue at the back of the eye. "It can feel as though a curtain is falling over one eye or a dark shadow briefly blocks your vision before everything returns to normal," explains Dr Mangesh Udar.
Because the symptoms disappear quickly, many people fail to seek medical help. Doctors consider amaurosis fugax the eye's equivalent of a transient ischaemic attack (TIA) or "mini stroke", making it an important warning sign that should never be ignored.
Symptoms you should never ignore
Dr Udar says immediate medical evaluation is necessary if you experience:
- Sudden blurring of vision in one eye
- Partial or complete vision loss lasting a few seconds or minutes
- A curtain, shadow or dark area moving across your field of vision
- Vision returning completely afterwards
Some people may also experience:
- Dizziness
- Weakness
- Numbness
- Difficulty speaking
These symptoms could indicate an underlying vascular problem rather than an eye condition.
What causes temporary vision loss?
According to Dr Udar, the most common cause is reduced blood flow to the retina.
Some of the factors that may be responsible for amaurosis fugax include:
- Narrowing of the carotid arteries
- High blood pressure
- Diabetes
- High cholesterol
- Heart rhythm problems, such as atrial fibrillation
- Blood clots temporarily blocking blood flow to the retina
Although migraines can also cause temporary vision changes, they usually affect both eyes and are often accompanied by headaches or flashing lights.
How is the diagnosis made?
If you experience an episode of temporary vision loss, your doctor may recommend several tests to identify the underlying cause.
These tests may include:
- Eye examination
- Retinal evaluation
- Blood pressure check
- Blood tests for cholesterol and blood sugar levels
- Ultrasound of the carotid arteries
- ECG or echocardiogram
- MRI brain and brain angiogram, if necessary
Don't ignore a warning your body is giving you
Treatment depends on the underlying cause and begins with a thorough neurological evaluation.
According to Dr Mangesh Udar, controlling blood pressure, cholesterol and blood sugar can significantly reduce the future risk. Some patients may also require blood-thinning medications, while others with severe narrowing of the carotid arteries may need to undergo a procedure known as carotid endarterectomy.
Just because your vision returns after a few minutes does not mean the danger has passed. Temporary vision loss in one eye can be an early warning sign of an impending stroke and should never be ignored.
Disclaimer: Tips and suggestions mentioned in the article are for general information purposes only and should not be construed as professional medical advice.
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