Individual differences |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |
Causes[edit | edit source]
There are many causes of blurred vision:
- Presbyopia -- Difficulty focusing on objects that are close. Common in the elderly. (Accommodation tends to decrease with age.)
- Cataracts -- Cloudiness over the eye's lens, causing poor night-time vision, halos around lights, and sensitivity to glare. Daytime vision is eventually affected. Common in the elderly.
- Glaucoma -- Increased pressure in the eye, causing poor night vision, blind spots, and loss of vision to either side. A major cause of blindness. Glaucoma can happen gradually or suddenly—if sudden, it is a medical emergency.
- Diabetic retinopathy -- This complication of diabetes can lead to bleeding into the retina. Another common cause of blindness.
- Macular degeneration -- Loss of central vision, blurred vision (especially while reading), distorted vision (like seeing wavy lines), and colors appearing faded. The most common cause of blindness in people over age 60.
- Floaters -- Tiny particles drifting across the eye. Although often brief and harmless, they may be a sign of retinal detachment.
- Retinal detachment -- Symptoms include floaters, flashes of light across your visual field, or a sensation of a shade or curtain hanging on one side of your visual field.
- Optic neuritis -- Inflammation of the optic nerve from infection or multiple sclerosis. You may have pain when you move your eye or touch it through the eyelid.
- Temporal arteritis -- Inflammation of an artery in the brain that supplies blood to the optic nerve.
- Migraine headaches -- Spots of light, halos, or zigzag patterns are common symptoms prior to the start of the headache. An ophthalmic migraine is when you have only visual symptoms without a headache.
Blurred vision may be a systemic sign of local anaesthetic toxicity
- Reduced blinking - Lid closure that occurs too infrequently often leads to irregularities of the tear film due to prolonged evaporation, thus resulting in disruptions in visual perception.
References[edit | edit source]
- Rang, H. P. (2003). Pharmacology, Edinburgh: Churchill Livingstone. Page 147
[edit | edit source]
|This page uses Creative Commons Licensed content from Wikipedia (view authors).|