Some Causes and Features of Eye Flashes and Floaters
Cause | Common Features* | Diagnostic Approach |
|---|---|---|
Eye disorders that are not worrisome | ||
Vitreous contraction floaters (floaters due to shrinking of the jellylike substance that fills the back part of the eyeball, called the vitreous humor) | A few small, translucent clumps or strands that
No recent change in the number or type of floaters No effect on vision | Examination by an ophthalmologist |
Detachment of the vitreous humor from the retina | A sudden increase in floaters, usually in older adults Floaters that resemble cobwebs One large floater that moves into and out of the field of vision Photopsias that come and go | Examination by an ophthalmologist |
Eye disorders that are serious | ||
Simple, sudden flashes of light that can look like lightning, spots, or stars (photopsias), that occur repeatedly or continuously Loss of vision that affects one area, usually what is seen out of the corners of the eye (peripheral vision) Loss of vision that spreads across the field of vision like a curtain Sometimes in people with risk factors for detachment of the retina (such as a recent eye injury, eye surgery, or severe nearsightedness) | Examination by an ophthalmologist | |
A tear in the retina | Photopsias Sometimes symptoms only in the peripheral field of vision | Examination by an ophthalmologist |
Vitreous hemorrhage (bleeding into the vitreous humor) | In people who have risk factors for this disorder (such as diabetes, a tear in the retina, sickle cell disease, or an eye injury) Usually loss of the entire field of vision (not in just one or more spots) | Examination by a doctor and generally an ophthalmologist Sometimes, ultrasonography of the retina |
Inflammation of the vitreous humor (as may occur when Toxoplasma parasites, fungi, or rarely cytomegalovirus infect the eye or caused by autoimmune disorders) | Pain Loss of vision affecting the entire field of vision Possibly affecting both eyes In people with risk factors for these infections (such as AIDS, injection drug use, and other conditions that weaken the immune system) | Examination by an ophthalmologist Sometimes, testing to detect microorganisms suspected of causing infection |
Disorders not related to the eyes | ||
Ocular migraine (migraines that cause vision symptoms) | Jagged lines that appear first in the center of the field of vision, then spread outward, and disappear after about 20 minutes Sometimes blurring of central vision Sometimes a headache after the disturbances in vision Sometimes in people known to have migraines | A doctor's examination |
* Features include symptoms and the results of the doctor's examination. Features mentioned are typical but not always present. Features occur in only one eye unless otherwise specified. | ||