• Diabetic retinopathy
• Age related macular degeneration
• Flashes and floaters
• Retinal detachment
• Retinal arterial blocks
• Retinal venous blocks

A variety of conditions can cause it, including:
posterior vitreous separation, retinal tears (breaks), and scarring on the surface of the retina. Some macular disease patients experience flashes in the central field of vision (straight ahead vision). Patients with successfully repaired retinal tears and detachments may have flashes for many months.

Actually the most common cause of light flashes is the vitreous humor pulling away from the retina. This happens in over 70% of the population as part of the normal aging process, or for other reasons that are not well understood at this time. It is usually accompanied by "floaters", which represent condensations of the vitreous jelly. By comparison, retinal breaks occur in approximately 6% of the population, and retinal detachments in about 0.06%. Light flashes occur in all three conditions.

Checking the blood will tell you the cholesterol levels. The "good cholesterol" should be kept high while the "bad cholesterol" should be kept low. You can use the chart below to see if your total cholesterol is high. Consult your doctor regarding the normal values.

Yes. Migraine can cause a jagged and flickering area of blocked vision with bright borders. It typically starts near the center of the vision and progresses to the peripheral vision before disappearing after about 30 minutes. This phenomenon is followed by a headache in only 50% of cases. Although patients describe this as occurring in one eye, in fact it occurs in the corresponding sides of the visual field in both eyes, as can be determined by covering one eye followed by the other when these are occurring.

Migraines are thought to be caused by blood flow disturbances to the visual part of the brain. Blood flow problems can also occur with cervical spine problems, inflammation of the optic nerve, and hardening of the arteries, as well as very low blood pressure. Low blood pressure can cause people to see stars or specks of light, particularly if they change position quickly. An example would be standing quickly from a sitting position or rising quickly after stooping or bending over. Pregnancy related high blood pressure (pre-eclampsia) can also cause light flashes.

No, but flashes can be related to retinal tears (breaks) or detachment, which can result in blindness if not treated.

Floaters are relatively transparent, vague, usually curved objects that are seen best when looking at a white piece of paper, blue sky, light colored ceiling, or wall. They sometimes look like cobwebs, worms, rings, dots, or specks. Eye movement makes floaters more visible as they swirl about like seaweed in the ocean surf.

They are usually caused by a clumping of pre-existing vitreous fibers in the eye. Therefore, doctors usually refer to them as vitreous condensations.

Some floaters are red blood cells or blood clots on the surface of the retina or floating in the vitreous. Blood cells in the vitreous may occur with some retinal tears but do not necessarily indicate a tear. Occasionally, the vitreous can pull on a blood vessel on the surface of the retina and cause bleeding without causing a tear of the retina. Vascular disorders such as diabetic retinopathy and sometimes vein occlusion can cause bleeding in the back of the eye.

Rarely, floaters may be inflammatory in origin. Diseases such as pars planitis and uveitis can cause the formation of clumps of white blood cells (cells that the body produces when there is inflammation).

In 5-30% of cataract surgery procedures a thin layer of tissue forms behind the intraocular lens implant causing a decrease in vision. A YAG laser is then used to make an opening the lens capsule which usually results in better vision, but can also cause floaters.

No, only a slight blockage of the vision at worst. Floaters are usually not detectable by visual testing unless they are very severe.
Importantly, floaters can be related to retinal detachment or a variety of vascular conditions such as diabetic retinopathy, which can result in blindness if not treated.

No, only a slight blockage of the vision at worst. Floaters are usually not detectable by visual testing unless they are very severe.
Importantly, floaters can be related to retinal detachment or a variety of vascular conditions such as diabetic retinopathy, which can result in blindness if not treated.

Very common. Over 70% of the population experiences these problems.

Very likely: in the case of a posterior vitreous separation, it is very common for the same condition to occur in the second eye within a year.

If light flashes are due to a posterior vitreous separation and no retinal breaks (tears) are found on careful examination with the pupil dilated, no treatment is necessary. If tears are found by the doctor, laser or occasionally freezing (cryo) treatment is needed. A vitrectomy can be used to remove floaters but is used only in select conditions, when the patient is very much incapacitated by floaters.