What Causes Cloudy Vision in One Eye?

Blurry vision is typically associated with the need for optical prescription or eyeglasses. However, monocular cloudy vision signifies a serious condition that needs immediate attention. Monocular cloudy vision can affect your visual field partly or entirely. In most cases, objects appear cloudy or out of focus and can interfere with your daily activities, even with contact lenses or glasses.

Cloudy vision in one eye is a typical sign of a medical eye emergency that an ophthalmologist should evaluate. Below are the main causes of cloudy vision in one eye.

1. Detached Retina

As the name suggests, retinal detachment occurs when the retina pulls away from the normal position at the rear side of the eye. Such a life-threatening occurrence leads to the sudden, unexplained onset of blurry vision with no pain. Vision changes occur coupled with:

• Decreased peripheral vision
• The appearance of a curtain in the visual field
• Eye floaters or light flashes

Retinal detachment often occurs due to advancing age, eye injury, or genetic predisposition. Delayed treatment of retinal detachment can cause permanent loss of vision. Therefore, you should seek medical attention immediately as it requires surgical repair.

2. Stroke

Stroke affecting visual parts of the brain can cause blurred vision in one or both eyes. Sudden onset of blurry vision and impaired eyesight is a key symptom of stroke. You should consult a medical professional if your eyes become blurry with the following other symptoms:

• Disorientation
• Severe headache
• Imbalance
• One-sided tingling and numbing of extremities, such as arms and legs
• Difficulty in understanding speech or speaking

Stroke is a serious medical emergency that requires urgent medical attention. The main goal of treatment is to restore blood flow to the brain. Sooner treatments have better outcomes.

3. Age-Related Macular Degeneration

AMD or age-related macular degeneration is a vision-threatening condition affecting the macula, the central part of the retina tasked with central and fine vision. AMD often starts with one eye before progressing to the second eye, causing sharp and central vision loss.

The two types of macular degeneration that causes cloudy vision include:

• Wet AMD – occurs when blood vessels form under the macula or behind the retina. The bleeding leaks into the eye tissues, scaring or damaging them.
• Dry AMD – macular thinning occurs with advanced age, leading to blurred vision. Dry AMD is the most common type of AMD, affecting 70 to 90% of patients. Early signs of dry AMD include white or tiny yellow debris under the retina.

Unfortunately, both types of AMD cannot be cured. However, your ophthalmologist can recommend the following to slow progression:

• Stop smoking
• Exercise regularly
• Eating a healthy/balanced diet
• Maintaining healthy cholesterol and blood pressure levels

Apart from blurry vision in one eye, most people with macular degeneration also find difficulties reading or driving, cannot see fine details, and have trouble making the right facial recognition.

4. Brain Tumor

Brain tumors can cause gradual blurry vision in one eye by exerting pressure on the parts that process eyesight in the brain. Blurry vision can occur in one or both eyes, depending on the location and size of the tumor. Signs of possible brain tumor include:

• Frequent headaches
• Balance and coordination problems
• Difficulty in speaking or concentrating
• One-sided weakness
• Memory loss or confusion

Treating brain tumors is often complicated. Whether they are malignant or benign, your physician will recommend surgical removal to prevent continued irritation and damage to other areas of the brain. Radiation therapy and chemotherapy are also preferred to kill the harmful cells that couldn’t be removed during the surgery.

5. Eye Infections

Eye infections caused by bacteria, fungi, and viruses can also cause blurry vision in one or both eyes. Common causative eye infections include:

• Conjunctivitis – also called pink eye, is the inflammation of the conjunctiva. This causes redness of the white part of the eye, swollen eyelids, itching/burning of the eye, and excessive tearing. Mild cases of conjunctivitis don’t affect vision.
• Endophthalmitis – is common after an eye injury, surgery, or corneal infection.
• Optic neuritis – while it has unknown etiology, it is widely associated with bacteria, viruses, and autoimmune conditions.
• Keratitis – is caused by bacteria, viruses, or fungi. Contact lens keratitis, which occurs due to poor use or cleaning of contact lenses, can cause cloudy vision in one eye.
• Uveitis – also results from infection, eye injury, or inflammations.
• Ocular herpes – is caused by the herpes simplex virus, which also causes genital herpes and cold sores.

While some eye infections resolve independently, you should consult your eye doctor if you experience itchiness, pain, red or bloodshot eyes, swelling, and other vision problems.

Bottom Line

Monocular blurry vision is a common eye condition with multiple mild to severe causes. Some causes of blurry vision are transient and easily treatable. However, sudden blurry vision might indicate a serious medical condition that requires immediate medical intervention. Cataracts, migraines, diabetes, and closed-angle glaucoma are other main causes of cloudy vision in one eye.