Retinal Detachment
Retinal Detachment
Definition
Retinal detachment is the separation of the retina of the eye from its underlying layer of tissue. This separation results in loss of vision. Retinal detachment is a medical emergency.
Description
The retina is a thin layer of light-sensitive cells about the size of a postage stamp located at the back of the eyeball. Underneath the retina lies a layer of cells called the retinal pigment epithelium (RPE). Beneath the RPE is a layer of blood vessels called the choroid. These blood vessels bring nutrients to and remove waste from the RPE. When light strikes the retina, chemical changes occur in the RPE that translate light patterns into nerve impulses. The nerve impulses are transmitted to the brain by the optic nerve, and in the brain they are converted into an image. When the retina is separated from the RPE and the choroid, these chemical changes do not occur and vision is lost.
Demographics
Estimates of the incidence of retinal detachment in the United States vary. Some researchers have found the rate to be between 1 in 10,000 and 1 in 15,000 population. The chance of detachment increases with age; most detachments occur in people between the ages of 45 and 70. Since Americans are living longer, the rate of retinal tears and detachments in the United States is expected to increase. Younger people are most likely to have a retinal detachment because of accidental eye injury.
Causes and symptoms
Causes
Risk factors for retinal detachment include:
- severe nearsightedness
- thinning of the retina at its outside edges (lattice degeneration)
- diabetic retinopathy when abnormal new blood vessels grow around the retina
- participation in contact sports such as football, ice hockey, or boxing
- being hit in the eye with a projectile such as a paintball or baseball
- using pilocarpine drops to treat glaucoma (high pressure in the eye)
- chronic eye infection (uveitis)
- cataract removal when the lens capsule is completely removed and the vitreous gel is disturbed. Complete lens capsule removal has been done infrequently in the United States since 1990, but the procedure accounts for about 30 to 40% of retinal detachments internationally.
There are three types of retinal detachments. Although their causes are different, their signs and symptoms are the same, and all can result in impaired vision. Rhegmatogenous detachments (“rhegma” means to break) occur because a tear in the retina allows fluid to seep between the retina and the RPE.
QUESTIONS TO ASK YOUR DOCTOR
- What type of retinal repair do you plan to do?
- Will I have a gas bubble? How long will it last?
- Will this be an inpatient or outpatient procedure?
- Will I have general or local anesthesia?
- What complications are common for this type of surgery?
- How long will it be before I can go back to work or my daily routine?
- What are my options if this surgery is not successful?
- How many of these operations do you perform each year?
- If my case is complicated, would you consider referring me to a specialized eye hospital for a second opinion or treatment?
The eye is filled with a jelly-like substance called the vitreous gel. The retina tears because as people age, the vitreous gel thickens and shrinks. As it does, it pulls the retina away from the RPE. Shrinking of the vitreous does not always cause a tear, but when it does, fluid can seep between the retina and the RPE, and the retina then peels off the RPE the same way wallpaper peels off a wall where there is a water leak. This is the most common kind of retinal detachment.
Exudative retinal detachments occur when fluid leaks out of the blood vessels in the choroid and accumulates under the retina. There is no tear in the retina, but the retina and the RPE are separated in the same way that the layers of skin are separated in a blister that has not broken. Exudative detachments occur because of inflammatory disease, tumors, or injury to the eye.
Tractional retinal detachments occur because scar tissue on the retina contracts and pulls the retina off the RPE. This is the least common type of retinal detachment.
Symptoms
The classic symptoms of a retinal tear or a retina detachment are flashing lights around the edge of the field of vision and a heavy shower of floaters . The vitreous gel pulling on the retina causes the sensation of flashing light. This pulling does not always cause a tear. Floaters are bits of solid material that have condensed in the vitreous. They look like tiny black specks, although they can also appear as a large cloudy blob in the field of vision. Individuals can have floaters for reasons other than a retinal tear. However, anyone who suddenly sees floaters or flashing lights should see an ophthalmologist immediately.
Once the retina has begun to detach, a sold black spot will appear in the field of vision and grow larger as more and more of the retina detaches. If left untreated, the retina will completely detach and total vision will be lost in that eye.
Diagnosis
A detached retina is usually diagnosed by an ophthalmologist who will refer the patient to a retina specialist. When the eye is dilated, the doctor will use a bright light and magnifying instrument to see if the retina is torn or detached.
Treatment
Some small retinal tears can be treated with cold laser surgery in which tissue around the tear is frozen to tack the retina back on to the underlying tissue. This procedure can be done in a doctor's office. The number, size, location, and cause of the tear determine whether this procedure is appropriate.
Larger tears and detachments require hospital surgery under local or general anesthesia . A retina specialist does this very delicate surgery. Patients may need to stay in the hospital overnight. Three different surgical operations can be performed depending on the specifics of the detachment.
- Pneumatic retinoplexy. This procedure is usually performed on an outpatient basis with the patient under local anesthesia. A laser is used to seal the retinal tear. Gas is then injected into the vitreous cavity. The gas forms a bubble that pushes the retina flat against the back of the eyeball, so that it can reattach. The gas gradually disappears as it is absorbed over a period of several weeks. During this time, the patient may have to keep his or her face parallel to the floor most of the time so that the gas holds the retina in the correct position to encourage reattachment.
- Scleral buckle. This surgery is done in a hospital under local or general anesthesia. The surgeon seals the holes in the retina using either heat or cold or a laser. Next, a small silicon or plastic belt called a scleral buckle is tightened around the outside of the eyeball and sewn into place. This compresses the eye, helps the retina to reattach, and reduces the chance of the vitreous gel pulling the retina away from the underlying tissue in the future.
- Vitrectomy. This procedure is used for large tears, situations in which there is bleeding into the vitreous cavity, abnormal blood vessel growth, scar tissue, and severe infection. In a vitrectomy, the vitreous gel is removed from the eye, retinal tears are sealed and abnormalities corrected through very delicate surgery. Gas is injected into the vitreous cavity and usually a scleral buckle is put in place. The patient keeps his or her head facing the floor for several weeks to keep the gas pressing against the retina until it can reattach. Gradually the gas is reabsorbed and fluid fills the vitreous cavity.
KEY TERMS
Cataract —A condition in which the lens of the eye becomes cloudy and visual acuity is lost. Cataracts can be corrected by outpatient surgery.
Diopter —A unit of measure of the power of a corrective lens. Negative diopter measurements indicate nearsightedness and positive diopter units indicate farsightedness.
Macula —The sensitive center of the retina that is responsible for detailed central vision.
Prognosis
Untreated retinal detachment leads to permanent blindness in the affected eye. About 80% of people experience successful retinal re-attachment after surgery. In some people the retina re-detaches, usually 6 to 8 weeks after surgery, and the surgery must be repeated a second, or even a third, time. Even with successful reattachment there is almost always some loss of vision. The amount of vision lost is directly related to the degree to which the retina detached and the length of time it remained unattached. People whose macula detach almost always lose significant visual acuity.
People who have a gas bubble in the eye often develop a cataract (clouding of the lens of the eye) and may need cataract surgery. New prescription glasses are needed after retinal surgery. Medicare and some insurance policies will pay part or all of the cost for these, since the prescription change is the result of eye surgery. About 15% of people who have a retinal detachment in one eye go on to have detachment in the other eye. Regular eye examinations are essential to detect any changes in either eye.
Prevention
Retinal tears cannot be prevented. Prompt attention to symptoms such as floaters and light flashes in the eye can sometimes prevent a retinal tear from developing into a detachment. Eye safety should be practiced by those participating in sports.
Caregiver concerns
Caregivers should be aware that a retinal detachment is a medical emergency that needs immediate attention. The greater the amount of retina that is detached and the longer it remains unattached, the more likely there will be serious vision loss.
If the patient has a gas bubble in the eye, during the first few weeks caregivers can take on tasks and make adjustments in daily living so that the patient can keep his or her face downward. Correct positioning of the head is important in a successful outcome to surgery. Caregivers should also understand that although vision stabilizes after successful reattachment surgery, visual acuity rarely returns to pre-detachment levels. Depth perception is often affected, and good direct illumination may be necessary for reading to be comfortable.
Resources
BOOKS
Kreissig, Ingrid. Primary Retinal Detachment: Options for Repair. New York: Springer Verlag, 2005.
The Official Patient's Sourcebook on Retinal Detachment: Directory for the Internet Age. San Diego, CA: Icon Health Publications, 2005.
OTHER
“Retinal Detachment.” Mayo Clinic. November 6, 2006 [cited April 1, 2008]. http://www.mayoclinic.com/health/retinal-detachment/DS00254.
“Retinal Detachment.” MedicineNet.com. October 26, 2007 [cited April 1, 2008]. http://www.medicinenet.com/retinal_detachment/article.htm.
“Retinal Detachment.” National Eye Institute. February 2008 [cited April 1, 2008]. http://www.nei.nih.gov/health/retinaldetach/index.asp.
ORGANIZATIONS
EyeCare America Foundation of the American Academy of Ophthalmology, PO Box 429098, San Francisco, CA, 94142-9098, (877) 887-6327, (800) 324-3937, (415) 561-8567, [email protected], http://www.eyecareamerica.org.
National Eye Institute, 2020 Vision Place, Bethesda, MD, 20992-3655, (301) 496-5248, [email protected], http://www.nei.nih.gov.
Tish Davidson A. M.
Retinal Detachment
Retinal Detachment
Definition
Retinal detachment is movement of the transparent sensory part of the retina away from the outer pigmented layer of the retina. In other words, the moving away of the retina from the outer wall of the eyeball.
Description
There are three layers of the eyeball. The outer, tough, white sclera. Lining the sclera is the choroid, a thin membrane that supplies nutrients to part of the retina. The innermost layer is the retina.
The retina is the light-sensitive membrane that receives images and transmits them to the brain. It is made up of several layers. One layer contains the photoreceptors. The photoreceptors, the rods and cones, send the visual message to the brain. Between the photoreceptor layer (also called the sensory layer) and the choroid is the pigmented epithelium.
The vitreous is a clear gel-like substance that fills up most of the inner space of the eyeball. It lies behind the lens and is in contact with the retina.
A retinal detachment occurs between the two outermost layers of the retina—the photoreceptor layer and the outermost pigmented epithelium. Because the choroid supplies the photoreceptors with nutrients, a detachment can basically starve the photoreceptors. If a detachment is not repaired within 24-72 hours, permanent damage may occur.
Causes and symptoms
Several conditions may cause retinal detachment:
- Scarring or shrinkage of the vitreous can pull the retina inward.
- Small tears in the retina allow liquid to seep behind the retina and push it forward.
- Injury to the eye can simply knock the retina loose.
- Bleeding behind the retina, most often due to diabetic retinopathy or injury, can push it forward.
- Retinal detachment may be spontaneous. This occurs more often in the elderly or in very nearsighted (myopic) eyes.
- Cataract surgery causes retinal detachment 2% of the time.
- Tumors can cause the retina to detach.
Retinal detachment will cause a sudden defect in vision. It may look as if a curtain or shadow has just descended before the eye. If most of the retina is detached, there may be only a small hole of vision remaining. If just a part of the retina is involved, there will be a blind spot that may not even be noticed. It is often associated with floaters —little dark spots that float across the eye and can be mistaken for flies in the room. There may also be flashes of light. Anyone experiencing a sudden onset of flashes and/or floaters should contact their eye doctor immediately, as this may signal a detachment.
Diagnosis
If the eye is clear—that is, if there is no clouding of the liquids inside the eye—the detachment can be seen by looking into the eye with a hand-held instrument called an ophthalmoscope. To evaluate the blood vessels in the retina, a fluorescent dye (fluorescein) may be injected into a vein and photographed with ultraviolet light as it passes through the retina. Further studies may include computed tomography scan (CT scan), magnetic resonance imaging (MRI), or ultrasound study. Other lenses may be used to examine the back of the eyes. One example is binocular indirect ophthalmoscopy. The doctor dilates the patient's eyes with eyedrops and then examines the back of the eyes with a handheld lens.
Treatment
Reattaching the retina to the inner surface of the eye requires making a scar that will hold it in place and then bringing the retina close to the scarred area. The scar can be made from the outside, through the sclera, using either a laser or a freezing cold probe (cryopexy). Bringing the retina close to the scar can be done in two ways. A tiny belt tightened around the eyeball will bring the sclera in until it reaches the retina. This procedure is called scleral buckling and may be done under general anesthesia. Using this procedure permits the repair of retinal detachments without entering the eyeball. Sometimes, the eye must be entered to pump in air or gas, forcing the retina outward against the sclera and its scar. This is called pneumatic retinopexy and can generally be done under local anesthesia.
If all else fails, and especially if there is disease in the vitreous, the vitreous may have to be removed in a procedure called vitrectomy. This can be done through tiny holes in the eye, through which equally tiny instruments are placed to suck out the vitreous and replace it with saline, a salt solution. The procedure must maintain pressure inside the eye so that the eye does not collapse.
Prognosis
Retinal reattachment has an 80-90% success rate.
Prevention
In diseases such as diabetes, with a high incidence of retinal disease, routine eye examinations can detect early changes. Early treatment can prevent both progressing to detachment and blindness from other events like hemorrhage. The most common problem is weakness of blood vessels that causes them to break down and bleed. When enough vessels have been damaged, new vessels grow to replace them. These new vessels may grow into the vitreous, producing blind spots and scarring. The scarring can in turn pull the retina loose. Other diseases can cause the tiny holes and tears in the retina through which fluid can leak. Preventive treatment uses a laser to cauterize the blood vessels, so that they do not bleed and the holes, so they do not leak.
Good control of diabetes can help prevent diabetic eye disease. Blood pressure control can prevent hypertension from damaging the retinal blood vessels. Eye protection can prevent direct injury to the eyes. Regular eye exams can also detect changes that the patient may not be aware of. This is important for patients with high myopia who may be more prone to detachment.
Resources
ORGANIZATIONS
American Academy of Ophthalmology. 655 Beach Street, P.O. Box 7424, San Francisco, CA 94120-7424. 〈http://www.eyenet.org〉.
American Optometric Association. 243 North Lindbergh Blvd., St. Louis, MO 63141. (314) 991-4100. 〈http://www.aoanet.org〉.
KEY TERMS
Cauterize— To damage with heat or cold so that tissues shrink. It is an effective way to stop bleeding.
Diabetic retinopathy— Disease that damages the blood vessels in the back of the eye caused by diabetes.
Saline— A salt solution equivalent to that in the body-0.9% salt in water.
Retinal Detachment
Retinal detachment
Definition
Retinal detachment is a serious eye disorder in which the retina, a thin tissue of cells located in the back of the eye, separates from the underlying tissue layers.
Description
There are three layers of the eyeball. The outer, tough, white layer is called the sclera. Lining the sclera is the choroid, a thin membrane that supplies nutrients to part of the retina. The retina is located at the back of the eye and consists of three cellular layers.
The retina contains the light-sensitive receptors for sight and processes visual images. A retinal detachment occurs between the two outermost layers of the retina, the photoreceptor layer that receives light and the outermost pigmented epithelium. When a tear in the retina occurs, the fluids in the eye may leak and pull the retina out of place, or detach it from the layers. Because the choroid supplies the photoreceptors within the retina with nutrients, a detachment can basically starve the photoreceptors. If a detachment is not repaired within 24–72 hours, permanent damage may occur.
Causes & symptoms
Several conditions may cause retinal detachment:
- Scarring or shrinkage of the vitreous (substance comprising the insides of the eye) can pull the retina inward.
- Small tears in the retina allow liquid to seep behind the retina and push it forward.
- Injury to the eye can loosen the retina. Trauma is the most common cause of retinal detachment in children, although it is comparatively unusual in the adult population.
- Bleeding behind the retina, most often due to diabetic retinopathy or injury, can push it forward.
- Retinal detachment may be spontaneous. This occurs more often in the elderly or in very nearsighted (myopic) eyes.
- Cataract surgery causes retinal detachment 2% of the time.
- Myopia .
- Diabetes.
- Congenital factors (those that people are born with).
- Family history of retinal problems.
- High blood pressure.
- Stress .
- Tumors.
Retinal detachment will cause a sudden defect in vision. It may look as if a curtain or shadow has just descended before the eye. If most of the retina is detached, there may be only a small hole of vision remaining. If only a portion of the retina is involved, there will be a blind spot that may not even be noticed. Retinal detachment is often associated with floaters, which are little dark spots that float across the eye and can be mistaken for flies in the room. There may also be flashes of light. Anyone experiencing sudden flashes of light or floaters should contact his/her eye doctor immediately since these may be symptoms of detachment.
Diagnosis
Diagnosis of retinal detachment should be done by an ophthalmologist. A person who has flashes, floaters, or has a curtain-like blockage of their visual field should see an ophthalmologist immediately because early treatment is required to prevent loss of sight. An optometrist may also diagnose retinal detachment during a routine eye examination.
Treatment
No alternative treatment is recommended for acute retinal detachment. Vision may be lost if the problem is
not diagnosed and attended to promptly. However, some alternative therapies such as behavioral optometry prescribe eye relaxation exercises and use techniques that attempt to prevent and naturally heal myopia (near-sightedness). Nearsighted (myopic) people are at greatest risk for retinal detachment. Some alternative therapies that reduce stress to the eyes may promote general eye health. Also, alternative treatments to control high blood pressure such as diet, Chinese herbs, massage for stress relief, relaxation exercises, and yoga , may also indirectly prevent retinal damage by reducing high blood pressure and relieving stress. Antioxidants such as bilberry may also be used to decrease inflammation.
Allopathic treatment
Traditional treatment of retinal detachment involves immediate surgery to repair the retina. Small holes or tears may be sealed with a laser or with cryotherapy (freezing) under local anesthesia in a doctor's office. More extensive repairs are done in the hospital under general anesthesia. These may involve injection of silicone oil to help the retina reattach.
Expected results
Retinal detachment is a serious condition that can result in blindness. If retinal detachment is diagnosed in its early stages and repair is made quickly, the patient's sight usually returns to normal. If the retina is fully detached, and extensive surgery is needed, the patient's sight may be partially or fully restored. The amount of restoration depends on the severity of the damage and how soon it is treated.
Prevention
To prevent retinal detachment, people should be keenly aware of eye function and diseases that may affect it. Regular eye examinations can detect changes that the patient may not notice. In such diseases as diabetes, with a high incidence of retinal disordes, routine eye examinations can detect early changes. Good control of diabetes can help prevent diabetic eye disease. High blood pressure and stress should be controlled daily. Blood pressure control can prevent hypertension from damaging the retinal blood vessels, and stress management techniques can also reduce blood pressure. Wearing eye protection can also prevent direct injury to the eyes.
Early treatment can prevent both progressing to detachment, and blindness from other events like hemorrhage. Other diseases can cause the tiny holes and tears in the retina through which fluid can leak. Preventive treatment uses a laser to cauterize the blood vessels so that they do not bleed and seals the holes so they do not leak.
Resources
PERIODICALS
Butler, T. K. H., A. W. Kiel, and G. M. Orr. "Anatomical and Visual Outcome of Retinal Detachment Surgery in Children." British Journal of Ophthalmology 85 (December 2001): 1437-1439.
"Eye Disorders: Retinal Detachment." Harvard Health Letter (December 1, 1998).
Jonas, Jost B., et al. "Retinal Redetachment After Removal of Intraocular Silicon Oil Tamponade." British Journal of Ophthalmology 85 (October 2001): 1203.
ORGANIZATIONS
American Academy of Ophthalmology. P.O. Box 7424, San Francisco, CA 94120-7424. (415) 561-8500.
American Optometric Association. 243 North Lindbergh Blvd., St. Louis, MO 63141. (314) 991-4100.
Angela Woodward
Rebecca J. Frey, PhD