The space between the crystalline lens of the eye and the retina is filled with a transparent, dense material, which is called vitreous.
In a newborn baby, the vitreous is compact and firm, like jelly and it is fixedly attached to the retina. However, as someone grows older the vitreous becomes less firm, fluidizes and may be detached from the back of the eye. This phenomenon is called vitreous detachment. It is a very common and usually harmless condition.
As the vitreous tends to be detached from the retina, light flashes or floaters usually appear in someone's vision. More specifically, floaters are caused by tiny pieces of vitreous cells, which "swim" in the vitreous space and create shadows on the retina. Flashes occur when the vitreous's pulling movements act on a sensitive retina.
More serious causes of floaters and illuminations also exist. Tears, retinal detachment, inflammation, hemorrhage or a head injury may lead to floaters.
Occasionally flashes are caused by neurological problems like a headache or a migraine.
Migraine flashes occur in both eyes and usually last for 20 to 30 minutes till the headache beginning.
Signs and symptoms
Black spots seem to float in one's vision area separately or altogether
Moving or stable spots
Flashes that blink and become more obvious when our gaze is stable on a bright point, like the blue sky
Symptoms that may indicate a more serious problem are:
Sudden decrease of vision along with flashes and floaters
Shadows like a curtain which prevent a part or all of the vision
Sudden increase of the floaters number
Check and diagnosis
You should visit your eye doctor if you realize a sudden appearance of floaters, flashes or some kind of curtain which blocks some or all of your vision. The doctor will dilate the pupils of your eyes with eye drops and then will examine the vitreous and the retina using an ophthalmoscope.
Treatments
Due to the risk of complications, surgery treatment is rarely indicated for vitreous detachment, unless the occurring floaters and illuminations strongly hinder one's vision.
Surgery treatment is also discussed when the occupation of the patient is such, that requires very accurate vision, like a professional driver. In these cases, the surgical removal of the vitreous (known as vitrectomy) can significantly help the patient.
Especially in recent years, a new type of vitrectomy (27 Gauge) is used. The tools are really thin, fact that makes the procedure almost non-traumatic. Thus, indication for surgery treatment is more often.
Nevertheless, the surgery treatment is rarely needed since floaters become significantly less obtrusive as weeks and months pass because they precipitate below the median line of the optical axis. However, vitrectomy may be indicated in a small group of patients with severe symptoms, as long as an objective assessment of the patient's visual problems is made.
If flashes and floaters are associated with another problem except from the posterior vitreous detachment, then surgery may be the appropriate treatment.
How to check your vision by yourselves
It is important to periodically check the vision of each eye. Many problems can be detected just by comparing the sight of our eyes.
In order to check your vision:
Cover each one of your eyes and focus with the other at a point straight ahead
Note the quality and accuracy of your central and peripheral vision as well as any other changes observed
Look for any obstructions, like curtains, in your peripheral vision
Look for floaters and illuminations
Note the duration and the strength of the symptoms
Report any new symptoms or changes in your vision to your ophthalmologist.
