Eye and vision care

What is a retinal detachment?

As explained in Anatomy of the Eye, the retina is the neurosensory tissue lining the inside of the eye. Photoreceptors on the retina receive light and transmit electrical impluses to the brain. When the retina detaches, it is lifted or pulled from its normal position. As a result, it is removed from its blood supply and source of nutrition. If it remains detached, the retina will degenerate and lose its ability to function. If not properly treated, a retinal detachment (also sometimes called a detached retina or a retinal tear) can result in permanent vision loss.

In some instances, a patient's retina may have small areas that are torn. These areas, known as retinal tears or retinal breaks, can lead to retinal detachment.

What are the symptoms of retinal detachment?

Symptoms of retinal detachment include:

• A sudden or gradual increase in the number of "floaters", little "cobwebs" or specks that float around within a patient's field of vision. Floaters are small, dark, shadowy shapes. They can look like spots, thread-like strands, or squiggly lines. A sudden increase in the number of floaters may indicate a retinal detachment or the clumping of vitreous collagen fibers. The spots are in fact the shadows these fibers are casting on the retina.
• Flashes of light inside the eye (photopsia)
• The appearance of a "curtain" or "veil" over the field of vision
• Blurred vision

Because most tears occurs in the periphery (side) of the retina, patients may not notice blurry side vision or loss of peripheral vision.

What causes retinal detachment?

Retinal detachments, regardless of their type (see below), are all characterized by changes to the jelly-like vitreous that fills the vitreous body of the eye. The vitreous accounts for about 80 percent of the eye's overall volume.

Over time—that is, with aging—the vitreous changes in consistency and may liquefy. It's not uncommon for the vitreous to also shrink. These changes may progress to the point that the vitreous sags and pulls away from the retina in what is known as posterior vitreous detachment or vitreous collapse. Aside from causing the appearance of new or different floaters a person's field of vision, these conditions don't cause serious problems and rarely affect a person's vision. Common floaters appear over time and although annoying, they are rarely a problem; they seldom require treatment.

However, if vitreous adheres to the retina and pulls at it as it shifts or sags, a patient may experience photopsia—flashes of sparkling lights. These flashes and increased floaters are usually indicative of a far more serious problem. When the pull on the retina is strong enough, it may tear, leaving a jagged flap.¹

Such tears can lead to retinal detachment. Detachment occurs when vitreous fluid starts to leak underneath the retina at places opened by retinal tears. As vitreous fluid collects, areas of the retina surrounding these defects may begin to peel away from the the choroid or retinal pigmented epithelium. Areas where the retina has detached are separated from their blood supply and source of nutrition and as a result, they lose their ability to see.

Detachments that go undetected and untreated can progress, eventually involving the entire retina and resulting in a complete loss of vision.

Are there different types of retinal detachment?

There are three types of retinal detachment: rhegmatogenous, tractional, and exudative.

Rhegmatogenous

Rhegmatogenous retinal detachments are the most common. They take their name from rhegma, meaning "rent" or "break." In a rhegmatogenous retinal detachment, a tear or break in the retina allows vitreous fluid to get under the retina and separate it from the retinal pigment epithelium, the pigmented cell layer that nourishes the retina.²

Tractional

Less common, a tractional retinal detachment occurs when scar tissue on the retina's surface contracts, causing the retina to separate from the retinal pigment epithelium. Adhesions between the vitreous gel and the retina may result in a retinal tear or break. The most common causes of tractional retinal detachment include proliferative diabetic retinopathy, sickle cell disease, advanced retinopathy of prematurity, and penetrating trauma.³

Exudative

Exudative retinal detachment is caused by inflammatory disorders or tumor growth, trauma/injury to the eye, or retinal diseases. In an exudative retinal detachment, fluid leaks into the area underneath the retina, but there are no tears or breaks in the retinal tissue.⁴

Who's at risk for retinal detachment?

Although more common in people over the age of 40, retinal detachment can occur at any age. Retinal detachment is more common in men than in women and affect caucasians more often than blacks. Retinal detachment also occurs more often in people of Jewish ethnicity. There are other factors that may predispose people to retinal detachment. Retinal detachment may occur in people who:⁵

• are extremely nearsighted
• have suffered a retinal detachment in the other eye
• have a family history of retinal detachment
• have had cataract surgery
• people with certain eye conditions such as posterior vitreous detachment, lattice degeneration, x-linked retinoschisis, degenerative myopia, and uveitis are at increased risk.
• have had an eye injury

How is retinal detachment treated?

By carefully examining your retina with the aid of an ophthalmosope, your ophthalmologist will be able to determine whether you have a retinal hole. An ophthalmoscope allows your ophthalmmologist to view the inside of your eyes in great detail and in three dimensions.

If blood in the vitreous body prevents a clear view of the retina, ultrasonography (sound waves) may be used to get a precise picture of the retina. Ultrasonography sends sound waves through the eye to bounce off the retina, presenting a clear picture of it on a monitor. This picture allows your doctor to view the retina and other structures within your eye to determine to what extent they may be damaged.⁶

Surgery is the only treatment for retinal tears, retinal holes, and retinal detachment.

Laser surgery (photocoagulation) and cryopexy

In the case of small retinal holes and tears, laser photocoagulation or freeze therapy called cryopexy is usually performed in the doctor's office. During laser surgery, pinpoints of laser light are used to make tiny burns around the hole. The burns cause scarring, which serves to "weld" the retina back into place. Photocoagulation requires no surgical incision, and it causes less irritation to the eye than does cryopexy.⁷

Cryopexy is a procedure in which the area around the hole or tear is frozen; this helps reattach the retina. After the application of a local anesthetic, a freezing probe is applied to the surface of the eye, directly over the area of retinal defect. The freezing produces an inflammation that leads to formation of a scar. As in photocoagulation, the scar tissue seals the hole(s) and "welds" the retina in place.⁸

Cryopexy is generally reserved for cases in which retinal tears are difficult to reach with a laser—tears along the retinal peripherpy. Cryopexy patients often experience red and swollen eyes following surgery.

Surgery for retinal detachment

Extensive retinal detachments are treated surgically, requiring the patient to stay in the hospital. Scleral buckling is the most common surgery for repairing retinal detachment. First, retinal tears are treated with cryopexy. Then, the surgeon will indent ("buckle") the sclera (the white part of the eye) with a piece of silicone. The silicone may be in the form of either a soft sponge or a solid piece. By closing the tear and reducing the circumference of the eyeball, the buckle prevents further fluid from pulling and separating from the retina.⁹

The scleral buckle is stitched in place and remains a permanent part of the patient's eye.

It may be necessary to also perform a vitrectomy. During a vitrectomy, a retina specialist makes a tiny incision in the sclera through which he or she then places a series of tiny instruments into the eye. A light probe illuminates the inside of the eye. A cutter is used to remove diseased vitreous, a gel-like substance that occupies the center of the eye and helps it maintain a round shape. An infusion tube is used to replace the volume of removed tissue with a balanced saline solution; this is done to maintain the normal pressure and shape of the eye.¹⁰

A gas bubble is often injected into the eye to help replace the vitreous and to reattach the retina. This gas bubble pushes the retina back against the wall of the eye. During the recovery process, the gas bubble eventually breaks up, and the eye produces fluid to replace it and to fill the eye. In some cases, a synthetic substance, such as silicone oil, is also inserted to push the retina back into place.

How successful are these treatments?

Modern therapies boast an excellent (90 percent) success rate. Nevertheless, some patients with a retinal detachment may require a second treatment. The outcome of such procedures is not always predictable; the impact on a patient's vision may not be known for several months following treatment. Despite repeated surgery and even under the most favorable of circumstances, treatment sometimes fails and vision may be lost. Outcomes are generally best when the retinal detachment is repaired before the macula (the center portion of the retina associated with fine, detailed vision) is affected and detaches. This is why it's vitally important to see an eye care professional immediately if you experience a sudden or gradual increase in the number of floaters, light/dark flashes, or a dark curtain over your field of vision.

Recovery

Following any surgery for retinal detachment, you can expect your eye to be red, swollen, watery, and sore. These symptoms may persist for up to a month following surgery. Your doctor may prescribe antibacterial and anti-inflammatory eyedrops to help the healing process. You'll be told to abstain from any strenuous activities (e.g., vacuuming, gardening, lifting anything over 10 pounds).

It will take 8 to 10 weeks for your eye to fully heal, and your doctor will request a number of visits with you during that time to assess your post-operative vision. If you wear glasses, your doctor will be able to determine whether you need a new prescription.

Following surgery, you may experience blurry vision for a few days. Healing from photocoagulation, cryopexy, or scleral buckling typically takes 10 to 14 days.

Following a vitrectomy, you may experience discomfort and a scratchy sensation in your eye. Your doctor may instruct you to lie prone (face down) or with your head cocked in order for the gas bubble to seal the retina. Avoid lying flat on your back: doing so may cause the bubble to move toward the crystalline lens of your eye, increasing your risk of cataract formation or of sudden pressure increase in your eye. This is why, in the first few weeks following surgery, it's very important to follow your doctor's instructions regarding sleeping positions.¹¹

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2. Retinal Detachment. National Eye Institute. (2004)
3. Retinal Detachment. National Eye Institute. (2004)
4. Retinal Detachment. National Eye Institute. (2004)
5. Retinal Detachment. National Eye Institute. (2004)
6. Retinal detachment — Causes. Mayo Foundation for Medical Education and Research. (1998–2004)
7. Retinal detachment — Screening and Diagnosis. Mayo Foundation for Medical Education and Research. (1998–2004)
8. Retinal detachment — Treatment. Mayo Foundation for Medical Education and Research. (1998-2004)
9. Retinal detachment — Treatment. Mayo Foundation for Medical Education and Research. (1998-2004)
10. Retinal detachment — Treatment. Mayo Foundation for Medical Education and Research. (1998-2004)
11. Retinal detachment — Treatment. Mayo Foundation for Medical Education and Research. (1998-2004)