What is cloudy vision?Cloudy vision is the loss of visual acuity or a blurring of visual perception that can affect one or both eyes. You may experience cloudy vision as a haziness or lack of clarity in your eyesight. It can be constant or intermittent, and one or both eyes can be affected. Cloudy vision may also dull your color perceptions, and it is often accompanied by glare or halos around lights. Cloudy vision may result from simple, harmless causes, such as discharge from the eyes or tearing, or it may result from serious causes such as acute glaucoma, vascular occlusions, or trauma to the eye. Although the term cloudy vision is sometimes used to describe blurred vision, these two changes in vision are slightly different. Blurred vision is most often caused by refractive error, which is corrected by eyeglasses or contact lenses to give you sharp vision. The most common cause of cloudy vision is cataract, which is a gradual loss of transparency in the lens inside your eye. Most cataracts develop as part of the aging process and are seen more frequently in older people, although cataract may develop earlier as a result of injury, diabetes, or prolonged use of certain drugs, including corticosteroids. Changes in or damage to the cornea, the clear “window” covering the front of your eye, may also cause cloudy vision. Although the cornea is a small structure, it is essential to good vision because all of the light rays that enter your eye pass through the cornea. Cloudy vision originating in the cornea may be caused by chemical burns, trauma, infections or inflammations of the cornea (keratitis), and numerous corneal dystrophies (conditions that cause abnormal buildup of fluid or other substances in the cornea). Less common causes of cloudy vision include diabetes, optic nerve disease, and macular degeneration. Because your eyes and vision are vital to your quality of life, it is important for you to contact your health care practitioner if you develop cloudy vision or any other eye symptoms that cause you concern. Occasionally, cloudy vision can be a sign of a medical emergency. Seek immediate medical care (call 911) if you experience cloudy vision as a result of chemical injury or trauma or if cloudy vision occurs along with other serious symptoms such as eye pain or sudden change in vision or blindness, sudden weakness or numbness on one side of the body, severe headache, or fainting, lethargy, or a change in level of consciousness. Seek prompt medical care (call 911) if your cloudy vision is persistent, increasing, or causes you concern.