Eye Floaters
Most people notice small spots, squiggly lines, or cobweb shapes drifting across their vision at some point. These are called eye floaters, and they often appear more clearly when looking at a bright background like the sky or a white wall. The natural aging process mainly causes eye floaters, as tiny pieces of the jelly-like substance in the eye (the vitreous) clump together and cast shadows on the retina.
Other causes include eye injuries, inflammation, or certain eye diseases. Some floaters are harmless, but a sudden increase in floaters, flashes of light, or a shadow in the vision could signal a more serious problem like retinal detachment. This article explains the common and less common causes of floaters, and when it makes sense to visit a professional for a closer look at your eyes.
Definition of Symptom
Eye floaters are tiny shapes or spots that drift across a person’s field of vision. They are often most noticeable when looking at something bright, like the sky or a white wall. These floaters can look like squiggly lines, dots, webs, or thread-like shapes. Some people describe them as cobwebs or shadows that seem to move when the eyes move, then dart away when trying to look directly at them.
The medical term for eye floaters is myodesopsias. This condition is very common, especially as people age. Floaters are usually painless and often harmless, but they can be annoying. In rare cases, a sudden increase in floaters can signal a more serious eye problem.
Common Features of Eye Floaters
| Appearance | Movement | Visibility |
|---|---|---|
| Dots, lines, webs | Drifts with vision | Brighter settings |
A full eye exam, especially a dilated eye exam, helps check for any signs of damage or disease when someone develops new floaters. During this exam, the doctor uses eye drops to widen the pupil and look at the back of the eye. Eye exams help rule out urgent problems like retinal tears or detachments. Only a qualified eye doctor can tell if floaters are harmless or linked to a more serious eye condition.
Possible Causes/Diseases Condition
Changes in the vitreous, a gel-like substance inside the eye, most often cause eye floaters. As people age, the vitreous can shrink and form small clumps or strands. These cast shadows on the retina, making floaters appear in vision.
- Aging and Posterior Vitreous Detachment: Aging is the most common cause. The vitreous pulls away from the retina in a process called posterior vitreous detachment.
- Retinal Tears and Retinal Detachment: Sometimes, the vitreous tugs on the retina and causes a tear. If left untreated, this can lead to retinal detachment, a serious condition where part of the retina comes loose.
- Eye Injury and Trauma: Eye trauma can cause bleeding or damage inside the eye, resulting in floaters.
- Other Medical Causes: Several other conditions may also cause floaters:
- Uveitis (especially posterior uveitis): Inflammation at the back of the eye.
- Vitreous hemorrhage: Bleeding into the vitreous.
- Diabetic retinopathy: Damage to the blood vessels of the retina.
- After cataract surgery or other eye surgeries.
Summary Table: Main Causes of Eye Floaters
| Cause | Description |
|---|---|
| Aging | Natural changes in vitreous |
| Posterior Vitreous Detachment | Vitreous separates from retina |
| Retinal Tear/Detachment | Retina is torn or lifted |
| Uveitis | Eye inflammation |
| Eye Trauma | Injury to the eye |
| Vitreous Hemorrhage | Bleeding in the vitreous |
| Diabetic Retinopathy | Retinal blood vessel damage |
| Cataract Surgery | Changes after eye operation |
Other Non-Disease Causes
Eye floaters do not always mean that there is a disease present. They can also develop from common, non-disease causes. The natural aging process is a main reason. As people get older, the gel-like liquid inside the eye, called the vitreous humor, changes. Over time, the collagen fibers in the vitreous clump together, casting shadows on the retina that people see as floaters.
Myopia, or nearsightedness, also increases the risk of floaters. People with nearsightedness often have longer eye shapes, which can stretch the vitreous and make floaters more likely. Minor eye injuries may cause floaters, too, even if they do not lead to serious inflammation. A bump or poke to the eye can briefly change the position of the vitreous or encourage small clumps to form.
Certain medical or eye procedures, such as eye surgery or laser treatments, can disturb the vitreous and lead to floaters. Floaters from these causes are usually harmless, especially if they are not joined by other symptoms like flashes of light or vision loss. Below is a table summarizing common non-disease causes:
| Cause | Related Structures |
|---|---|
| Aging of vitreous humor | Vitreous, collagen fibers, retina |
| Nearsightedness (myopia) | Retina, vitreous |
| Eye injury | Vitreous, retina |
| Eye procedures | Vitreous, macula |
How It Causes the Symptom
The vitreous, a gel-like substance inside the eye, changes over time and often causes eye floaters. As people age, the vitreous begins to shrink and some of its collagen fibers clump together. These clumps cast small shadows on the retina, which is how floaters appear in vision.
In other situations, the vitreous detaches from the retina. This process, called posterior vitreous detachment (PVD), is common and usually not painful, but it can cause a sudden increase in floaters and sometimes flashes of light.
Common Features of Floaters and Associated Symptoms
| Symptom | Description |
|---|---|
| Floaters | Small dots, lines, or cobweb shapes in vision |
| Light flashes | Sudden brief flashes, often with floaters |
| Eye pain | Usually not present with typical floaters |
| Photopsia | Seeing flashes of light in the eye |
Some people notice light flashes at the same time as new floaters. These flashes happen when the vitreous pulls on the retina, causing nerve cells in the retina to react. Eye injuries, inflammation, or bleeding in the eye increase the risk of floaters. Conditions such as uveitis or diabetic eye disease may create extra debris in the vitreous, leading to more floaters.
When floaters appear with severe light flashes, vision loss, or a “gray curtain” moving across the field of vision, these signs could signal a more serious issue, like a retinal tear. Immediate medical help is needed if these symptoms occur together.
Possible Complications
Most eye floaters do not lead to serious eye problems. However, some complications can happen, especially if floaters suddenly appear, change, or increase. A sudden rise in the number of floaters, especially with flashes of light, could point to a more serious problem. This might include:
- Retinal tear
- Retinal detachment
- Vitreous hemorrhage
These complications can lead to partial or permanent vision loss if not treated quickly. A table of possible complications:
| Complication | Possible Outcome |
|---|---|
| Retinal tear | May cause vision changes |
| Retinal detachment | Risk of severe vision loss |
| Vitreous hemorrhage | Blurred or blocked vision |
Seeing new floaters or experiencing loss of side vision can be a warning sign. People should have an eye exam if these symptoms appear to rule out serious conditions. People who have diabetes or have had eye surgery may face a higher risk for complications.
When to Seek Medical Attention
Most eye floaters are harmless and related to aging. However, sometimes you need to see a doctor right away. Seek medical attention immediately if you notice:
- A sudden increase in floaters
- Flashes of light in your vision
- Loss of side (peripheral) vision
- Sudden blurry vision
- Eye pain or redness
| Symptom | What It Might Mean | Action to Take |
|---|---|---|
| Sudden more floaters | Possible retinal tear | Call an eye doctor |
| Flashes of light | Possible retinal detachment | Visit clinic urgently |
| Peripheral vision loss | Retinal problem | Emergency visit |
| Floaters after eye injury | Bleeding or damage | Immediate care |
Do not wait to get help if you experience any of these problems. If you have had an eye injury, such as being hit in the eye, wear protective eyewear in the future to help prevent injury that may cause floaters or more serious eye problems. People who are very nearsighted (myopic) may also face a higher risk for floaters and retinal issues. Get regular eye exams in these cases.
