What is blurred vision? Blurred vision or blurry vision is a loss of sharp vision. You may experience sudden or gradual blurry vision in one or both eyes. Blurred vision can be a symptom of a variety of mild to serious diseases, disorders or conditions. Blurred vision can result from minor problems, such as nearsightedness or wearing the wrong eyeglasses. Blurred vision can also be a normal sign of aging. However, blurred vision can also result from infection, inflammation, trauma, malignancy, and other abnormal processes; therefore, you should discuss any vision changes with a medical professional. Certain types of vision changes can indicate a medical emergency, which can lead to loss of sight, such as with glaucoma, an eye injury, or retinal detachment, or loss of life, such as in the case of stroke or bleeding in the brain if you do not seek emergency care. Even temporary blurred vision should not be ignored because it can result from serious conditions, such as stroke, transient ischemic attack (TIA), hypertension, or epilepsy. Depending on the cause, blurred vision can begin suddenly and disappear quickly, such as when your eyes are refocusing on a far object after reading, or after sun overexposure. Blurred vision can also occur in sudden, severe episodes, such as blurred vision from a detached retina or head trauma. Blurred vision that is slow to develop and accompanied by additional symptoms, such as halos around lights, may be a sign of cataracts. Any change in vision should always be evaluated by a medical professional. Blurred vision can be a symptom of a serious disorder, such as encephalitis, a brain tumor, or retinal detachment. If you experience blurred vision with a sudden, severe headache, stiff neck, nausea or vomiting, seek immediate medical care (call 911).