What Causes Eye Floaters?

Eye floaters, the small dark shapes that appear in the eye, are generally caused by age-related changes in the eyes. They can appear as spots, lines, and webs. Eye floaters are often harmless and don't require treatment. In some cases, however, eye floaters can be caused by a serious condition such as retinal detachment that may require surgery. 

Anatomy

The retina is filled with a jelly substance called the vitreous, a hydrated extracellular matrix made primarily of water, collagen, and hyaluronan organized into a homogeneously transparent gel. Also called the vitreous humor, this jelly substance is crucial for vision since it helps the eye maintain its round shape and transmits light into the retina.

However, the vitreous doesn’t remain the same throughout life. When a person ages, the vitreous becomes more liquid and small collagen fibers clump together, casting shadows on the retina and creating the floaters people see. This common happens in people who are 50 years old or older. 

Symptoms

Eye floaters are often harmless. If they don’t cause discomfort or are not accompanied by other symptoms, there is no need to worry.

However, they can also be a sign of a serious diseases if they occur along with the following symptoms:

• The number of floaters increases suddenly
• Pain in the eye
• Floaters are combined with flashes
• Peripheral vision loss
• Blurred vision

Causes

Eye floaters are often a normal part of aging. However, they can also be linked to other conditions, including:

• Vitreous detachment: The most common symptom of vitreous detachment is a sudden increase in the number of floaters. People who have this condition can also see flashes. A person's risk of vitreous detachment increases as they age, so it is most common in people over 80. The fibers of the vitreous begins to pull away from the retina as someone gets older, resulting in this condition. In severe cases, it can lead to problems such as retinal detachment and macular hole
• Retinal detachment: This happens when the retina is pulled away from its normal position in the eye. A sudden increase in the number of eye floaters, flashes of light in one or both eyes, a shadow over vision are symptoms of this condition
• Uveitis: This is a group of inflammatory diseases that causes swelling and destroys eye tissues. These diseases can slightly reduce vision or lead to severe vision loss. Early symptoms include floaters, eye pain, blurry vision, and sensitivity to light
• Vitreous hemorrhage: This is bleeding in the vitreous. This can be a result of abnormal vessels that are prone to bleeding, normal vessels that rupture under stress, or extension of blood from an adjacent source. It is rare and occurs in seven cases per 100,000 population.  This condition is related to diseases like diabetic retinopathy. Blunt or perforating trauma is the most common cause of vitreous hemorrhage in people under 40
• Eye tumor: They can be malignant or benign, and it is not rare that eye tumors don't have symptoms. Depending on the part of the eye it grows or its stage, people with eye tumors may have floaters, visual field loss, blurry vision, and changes in the way the eye moves within the socket

Diagnosis

An eye care professional can diagnose the underlying condition causing eye floaters after performing an eye exam. The ophthalmologist or optometrist will dilate the patient’s pupil so they can see inside the eye and examine your floaters. They may also press on your eyes to check for signs of a retinal detachment or tear.

Treatment

Treatment for eye floaters depend on the cause. If eye floaters are not signs of any other problem, they don't need to be treated. People often stop noticing them after a while and will learn to live with the eye floaters. When the eye floaters are seriously impacting vision, surgery may be recommended. 

Vitrectomy is a surgical procedure that involves removing the vitreous from your eye and replacing it with a solution that mimics the vitreous. However, several risks are involved in this process. The patient can develop a retinal tear or cataracts. There is also no guarantee the surgery will remove all the floaters.

It is also possible to have a laser surgery that will break up groupings of floaters. Some people who have this treatment report improved vision; others notice little or no difference. The laser can potentially damage the retina.

A Word From Verywell

Eye floaters are not a cause for concern in most cases. They are a normal part of aging. It is natural that the eye system becomes weaker with age, just like other parts of the body. Whether you are experiencing floaters or not, it is essential to schedule an appointment with an eye care specialist every two years and more frequently for those over 60 and have a family history of glaucoma. It is the best way to make sure that your vision is healthy. For people with floaters, this can help catch and treat any conditions causing eye floaters early.