Don't ignore sudden vision loss in one eye
Temporary blurred vision in one eye could be an early warning sign of stroke
A brief episode of blurred vision in one eye may seem harmless, but neurologists warn that it should never be ignored. While many people assume it is caused by tiredness or eye strain, temporary vision loss can sometimes be an early warning sign of a stroke.
According to Dr Mangesh Udar, Consultant Neurologist at Manipal Hospitals, Baner, Pune, sudden blurring or loss of vision in one eye that clears within a few minutes may be caused by amaurosis fugax. This condition occurs when blood flow to the retina is temporarily reduced. The retina is the light-sensitive tissue located at the back of the eye, and it plays a vital role in vision.
Although the symptoms often disappear quickly, doctors say they may indicate a serious problem with blood circulation. In many cases, amaurosis fugax is considered the eye's equivalent of a transient ischaemic attack (TIA), commonly known as a mini-stroke. Recognising the symptoms early and seeking medical care can help reduce the risk of permanent vision loss or a major stroke.
People experiencing this condition often describe it as though a curtain or dark shadow suddenly falls over one eye before their vision returns to normal. Because the episode lasts only a few seconds or minutes, many people do not seek medical attention. However, experts stress that even a single episode should be evaluated by a doctor.
Symptoms that need urgent attention
Amaurosis fugax mainly affects one eye and usually develops suddenly. The most common symptom is blurred or complete loss of vision that lasts for a short period before returning to normal.
Some people may notice a dark shadow or curtain moving across their field of vision. Others may experience only partial blurring instead of complete vision loss. Although the symptoms disappear quickly, doctors say this does not mean the underlying problem has resolved.
In some cases, temporary vision loss may be accompanied by other neurological symptoms such as dizziness, weakness, numbness or difficulty speaking. These symptoms may suggest that the brain is also receiving reduced blood flow and require immediate medical attention.
Doctors advise anyone who experiences sudden vision loss in one eye, even if it lasts only a few minutes, to seek emergency medical evaluation rather than waiting for another episode.
Temporary vision changes caused by migraines are usually different. Migraine-related visual disturbances often affect both eyes and may include flashing lights, zigzag patterns or shimmering spots. They are also commonly associated with headaches. Amaurosis fugax, however, usually affects only one eye and is more closely linked to blood circulation problems.
Early diagnosis can prevent stroke
According to Dr Udar, the most common cause of amaurosis fugax is reduced blood flow to the retina. This can happen when a blood clot temporarily blocks an artery supplying the eye or when blood vessels become narrowed.
Several medical conditions increase the risk of developing this problem. These include high blood pressure, diabetes, high cholesterol, narrowing of the carotid arteries and heart rhythm disorders such as atrial fibrillation. These conditions can reduce blood flow or increase the risk of blood clots, making stroke more likely.
To identify the cause, doctors may recommend several tests. These usually include a detailed eye examination and retinal evaluation, blood pressure measurement, blood tests to check cholesterol and blood sugar levels, and an ultrasound of the carotid arteries to detect narrowing.
Depending on the patient's symptoms and medical history, doctors may also advise an electrocardiogram (ECG) or echocardiogram to examine heart function. In some cases, an MRI scan of the brain and a brain angiogram may be required to look for problems affecting blood vessels in the brain.
Treatment depends on the underlying cause. Managing blood pressure, diabetes and cholesterol levels plays an important role in reducing future stroke risk. Some patients may be prescribed blood-thinning medicines to prevent clot formation.
If severe narrowing of the carotid arteries is detected, surgery known as carotid endarterectomy may be recommended. This procedure removes plaque from the artery, improving blood flow to the brain and reducing the risk of stroke.
Neurologists emphasise that temporary vision loss should never be dismissed simply because eyesight returns to normal. A brief episode may be the body's first warning that blood supply to the brain or eye has been interrupted.
Early diagnosis and treatment can prevent serious complications, including permanent blindness or a major stroke. Anyone who experiences sudden blurred vision or temporary loss of vision in one eye should seek immediate medical evaluation instead of waiting for the symptoms to return. Recognising these warning signs and acting quickly can make a significant difference in protecting both vision and overall health.
Related News
