Decreased vision in one eye can appear suddenly or progress gradually. Identifying the underlying cause is important for preserving vision and preventing long-term complications.

Retinal detachment

The retina is a layer of nerve tissue at the back of the eye, responsible for receiving light and transmitting visual signals to the brain. When the retina detaches from the eyeball wall, this process is disrupted, leading to vision loss.

Patients with retinal detachment often notice more floaters than usual, flashes of light, or a sensation of a curtain obscuring part of their field of vision. This is an ophthalmological emergency, where vision can rapidly decline in a short time. If treated early, the chances of preserving vision are generally higher.

Blurred vision in one eye can be a sign of retinal disease. *AI-generated image*.

Optic neuritis

The optic nerve transmits signals from the eye to the brain. When this nerve becomes inflamed, patients may experience vision loss in one eye over several hours or days.

Beyond blurred vision, many also feel pain when moving their eyes, reduced color perception, or colors appearing less vibrant. The condition is sometimes linked to autoimmune diseases or neurological disorders. The extent of vision recovery depends on the cause and the timing of treatment.

Retinal vein occlusion

Retinal vein occlusion occurs when blood flow from the retina is obstructed. This condition can cause retinal swelling and affect vision.

Common symptoms include sudden vision loss or blurred vision in one eye, sometimes without pain. Patients with cardiovascular disease or metabolic disorders have a higher risk of retinal vein occlusion. Without proper monitoring and treatment, the condition can cause long-term vision damage.

Corneal damage

The cornea is the transparent layer at the front of the eyeball, helping to focus light for clear vision. Any damage to the cornea can reduce visual quality.

Common causes include: corneal abrasions, foreign objects in the eye, keratitis (corneal inflammation), or improper contact lens use. Patients often experience a gritty sensation, tearing, light sensitivity, and blurred vision in the affected eye. Most cases can recover well with early and appropriate treatment.

Chronic dry eye

Dry eye occurs when the eyes do not produce enough tears or when tear quality is poor. The condition can leave the corneal surface inadequately lubricated, leading to temporary blurred vision.

Symptoms often include a burning, gritty, stinging, or tired sensation in the eyes, especially after prolonged computer or phone use, or working in air-conditioned environments. For many, vision may improve after blinking or using artificial tears.

Unilateral blurred vision requires early examination if it appears suddenly, vision rapidly declines, or if accompanied by signs such as flashes of light, numerous floaters, a sensation of a dark curtain over the eye, eye pain, or pain when moving the eye. Prompt treatment of these conditions helps limit the risk of vision loss.

Bao Bao (Compiled)