Understanding Blurred Vision: Common Causes & Warning Signs

Blurred vision is something we all experience at one time or another. Whether from tired eyes or the occasional wearing of glasses, it’s an everyday and frequently harmless condition. But if blurred vision occurs too often or regularly, it might be a warning sign of a more serious underlying issue. Being aware of causes of blurred vision is essential so you can distinguish between when it’s just an annoyance and when it may signal something more important.

What Is Blurred Vision?

Blurred vision refers to any distortion or reduction in the sharpness of your vision. It can affect both eyes or just one, and the extent of the blurring can vary. Sometimes it’s caused by something simple like tired eyes, but in other cases, it can indicate a problem with the eyes, the brain, or your overall health.

What are the Common Causes of Blurred Vision?

There are a number of reasons why blurred vision may be experienced. Some are temporary, while others are treatable and even need to be operated on. Some of the most prevalent causes of blurry vision are:

Refractive Errors

Refractive errors are the leading cause of blurred vision. They take place when the eye’s shape keeps light from focusing directly onto the retina. Some of the most prevalent refractive errors include:

Nearsightedness (myopia): When distant objects appear blurry.
Farsightedness (hyperopia): When close objects appear blurry.
Astigmatism: Distortion of vision due to an irregularly shaped cornea or lens.
Presbyopia: Age-related difficulty in seeing objects up close.

These conditions are typically corrected with glasses, contact lenses, or refractive surgery.

Eye Strain and Blurred Vision

Eye strain is an extremely common cause of blurring of vision, particularly from extended periods at computer or TV screens. If we stare too long at a thing without changing the focus to allow for rests, the eye muscles get fatigued. Signs of eye strain are:

Blurred vision
Headache
Dry eyes
Neck or shoulder pain

Taking frequent breaks and observing the 20-20-20 rule (every 20 minutes, view something 20 feet away for 20 seconds) can help prevent and alleviate eye strain.

Sudden Blurred Vision

Sudden blurred vision may be frightening. It can occur in one eye or both eyes and sometimes be a sign of a medical condition, such as:

Diabetic Retinopathy: Excess blood sugar can harm the blood vessels of the retina and cause vision issues.
Macular Degeneration: This is an age-related maculopathy that occurs in the central region of the retina and can result in sudden changes in vision.
Cataracts: Clouding of the lens in the eye may result in blurred or foggy vision.

Sudden blurred vision, particularly if it is painful or accompanied by other symptoms, should be addressed immediately by seeking medical care.

Blurred Vision in One Eye

When there is blurred vision in only one eye, it may be an indication of a problem with the eye itself or the optic nerve. Some conditions that lead to blurred vision in one eye include:

Eye Infection: A condition such as conjunctivitis (pink eye) can result in blurred vision as well as redness.
Dry Eyes: Inadequate tears or inferior quality tears can result in dryness and blurred vision.
Retinal Issues: Blurry vision may be the result of a detached retina, macular degeneration, or diabetic retinopathy in one eye.

If you experience blurry vision in one eye, see an eye care professional to figure out the reason and how it should be treated.

Dizziness and Blurred Vision

Dizziness and blurred vision is more severe. This could mean your balance and vision are at risk. Such symptoms can be caused by:

Vestibular Disorders: The inner ear plays a very important role in balance, and disorders like Meniere’s disease or benign paroxysmal positional vertigo (BPPV) could cause dizziness and blurred vision.
Low Blood Pressure: If your blood pressure plummets unexpectedly, it might lead to dizziness and blurred vision.
Neurological Disorders: Brain conditions, like stroke or migraine, can lead to dizziness, blurred vision, and other associated symptoms.

Dizziness and blurred vision occurring simultaneously, especially when sudden, need to be examined by a physician as it might be a manifestation of an underlying serious illness.

Symptoms of Blurred Vision to Watch Out For

Blurred vision alone is a symptom, but there are certain other signs that can indicate that something is seriously amiss. The following are some other symptoms to watch out for:

Blurred Vision with Headache

If you have blurred vision with a headache, it could be an indication of:

Migraines: Migraines often cause vision changes, including blurry vision, before or with headache.
Elevated Eye Pressure: Glaucoma can cause blurry vision and headache.
Sinus Problems: Sinus infection or sinusitis could lead to eye pressure behind the eyes and thus cause blurry vision and headaches.

If you experience frequent or severe headaches, it is best to consult a doctor to rule out dangerous disorders.

Blurred Vision with Nausea

Blurred vision accompanied by nausea can signal issues like:

Migraine: As mentioned earlier, migraines can lead to both blurred vision and nausea.
Stroke: Nausea and sudden loss of vision could be signs of a stroke, particularly if accompanied by other signs like weakness or trouble with speech.

Nausea and blurred vision are dangerous signs that should be seen by a doctor.

Eye Pain and Blurred Vision

If you notice blurred vision along with eye pain, then it could be due to:

Glaucoma: An eye disease where the eye pressure increases, resulting in blindness.
Uveitis: Middle eye layer (uvea) inflammation can result in eye pain and blurred vision.
Infections: Eye infection or corneal ulcer can cause eye pain, redness, and blurred vision.

Pain in the eyes with hazy vision should always be treated seriously and evaluated by an eye care practitioner.

When to Be Concerned About Blurred Vision?

In the majority of instances, blurred vision is temporary and harmless, as long as it’s caused by eye fatigue or a small refractive error. There are certain situations however where blurred vision symptoms cannot be ignored. In the following situations, you should seek medical assistance:

Sudden blurred vision occurs out of nowhere.
You observe additional signs like headache, dizziness, or eye pain.
Blurred vision occurs in conjunction with loss of vision or vision impairment.
You suffer from associated illnesses like diabetes, hypertension, or heart disease.

Timely resolution of whatever issue your vision is going through will prevent future complications.

Conclusion

Blurry vision may at times be merely a nuisance, but it could also be indicative of a worse underlying condition. Regardless of the cause, be it eye fatigue, refractive problem, or a more debilitating one like macular degeneration or glaucoma, do take heed to the symptoms. If your blur vision is unexpected, persistent, or is otherwise accompanied by disturbing symptoms like dizziness, head pains, or pains in your eyes, don’t hesitate to consult an eye care specialist.