What Is A Detached Retina? What Causes A Detached Retina?

Editor's Choice
Main Category: Eye Health / Blindness
Article Date: 12 Nov 2009 - 0:00 PDT

email to a friend   printer friendly   opinions  

Detached retina, also known as retinal detachment is when the retina peels away, or detaches from its underlying layer of support tissue at the back of the eye. Initially, detachment might only occur in a small part of the retina, however, if not treated promptly the whole retina may peel off and the person will not be able to see from that eye.

In most cases detached retina only occurs in one eye. It is a medical emergency.

The retina is a thin layer of light sensitive nerve cells at the back of the eye. Light goes through the optical system of the eye and hits the retina, as it does on the film of a (non-digital) camera. The image produced by the light that hits the retina is translated into neural impulses and sent to the brain through the optic nerve - put simply, an image focuses on the retina, nerve cells process this information and send it via electrical impulses through the optic nerve to the brain.

According to the NHS (National Health Service), UK, detached retina affects approximately 1 in every 10,000 British people. Individuals who are more susceptible to develop this condition include short-sighted people, people with diabetes, patients who underwent complicated cataract surgery, and anybody who has received a hard blow to the eye.

According to Medilexicon's medical dictionary:

Retinal detachment is loss of apposition between the sensory retina and the retinal pigment epithelium.

Types of retinal detachment

Rhegmatogenous retinal detachment - a break, tear or hole develops in the retina, allowing liquid to pass from the vitreous space into the subretinal space between the sensory retina and the retinal pigment epithelium (the pigmented cell layer just outside the neurosensory retina).

Secondary retinal detachment - also known as exudative retinal detachment or serous retinal detachment. It is caused by inflammation, vascular abnormalities or injury which cause fluid to build up under the retina (there is no hole, break or tear).

Tractional retinal detachment - an injury, inflammation or neovascularization causes the fibrovascular tissue to pull the sensory retina from the retinal pigment epithelium.

What are the signs and symptoms of a detached retina?

A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor notice. For example, pain may be a symptom while a rash may be a sign.

• Photopsia - the patient experiences sudden flashes of light which are very brief and in the outside of center part of their vision (peripheral vision). The flashes more commonly occur when the eye moves.
• An enormous increase in the number of floaters. Floaters are bits of debris in the eye which make us see things floating in front of us, usually like little strings of transparent bubbles or rods that follow our field of vision as our eyes turn. Often it may be a ring of hairs or floaters on the temporal side of the central vision
• The eye feels somewhat heavy
• A shadow starts to appear in the peripheral vision. It gradually spreads towards the center of the person's field of vision
• A sensation that a transparent curtain is coming down over the field of vision
• Straight lines start to appear curved

What are the risk factors of retinal detachment?

A risk factor is something which raises the likelihood of developing a disease or condition. For example, obesity increases the risk of developing diabetes type 2; therefore, obesity is a risk factor for diabetes. The following may increase the risk of developing retinal detachment:

• Genetics - people with a close family relative who had retinal detachment have a higher risk of developing it themselves.
• Age - retinal detachment is much more likely to affect middle aged and elderly individuals than young people.
• Myopia - people who are short-sighted, especially those with severe myopia have a higher risk of developing the condition.
• Patients who underwent complicated cataract surgery are more susceptible to eventually having a detached retina.
• Recurrence - patients who have had retinal detachment have a risk of recurrence (it happens again).
• A blow - if you had a severe blow to the eye your chances of having retinal detachment are higher compared to those who did not receive a blow.
• Diabetes - especially if the diabetes is poorly controlled.

How is retinal detachment diagnosed?

If a GP suspects the patient may have retinal detachment they will be referred to an eye specialist (an ophthalmologist) who will be able to detect any faults, and probably they occurred.

What is the treatment for retinal detachment?

In order to find all the retinal breaks and seal them, as well as relieving present and future vitreoretinal traction (pulling) the patient has to undergo surgery. In fact, without surgery the risk of retinal detachment leading to blindness is enormous, some would say certain.

• Laser surgery (photocoagulation) - a laser beam is directed through a contact lens or ophthalmoscope. The laser makes burns around the retinal tear, resulting in scarring tissue which fuses the tissue back together.

• Cryopexy (freezing) - cryosurgery (cryotherapy) is the application of extreme cold to destroy abnormal or diseased tissue. In this case, the procedure produces a delicate scar that helps connect the retina to the wall of the eye.
• Pneumatic retinopexy - this procedure is more common if the detachment is uncomplicated. The surgeon may start by freezing (cryopexy) the tear area. A bubble is injected into the vitreous cavity of the eye, causing the retina to push against the tear and the detached area. The continuous pressure, which may go on for days, eventually makes the retina re-attach itself to the wall of the back of the eye.
• Scleral buckling - in the area where the retina has detached very thin bands of silicone rubber or sponge are sewn onto the sclera (outside white of the eye). The tissue around the area may be frozen or lasers may be used to scar the tissue.
• Vitrectomy - the vitreous gel is removed and a gas bubble or silicon oil bubble is used; this holds the retina in position. The wound is stitched. Silicon oil needs to be removed 2 to 8 months after the procedure.

According to the NIH (National Institutes of Health), approximately 85% of surgical procedures for retinal detachment are successful with one operation, the remainder will need subsequent surgeries. The patient should get his/her vision back a few weeks after treatment. If the macula was involved in the area of detachment visual acuity may never recover completely. Visual acuity refers to acuteness or clearness of vision.

There is a small risk of complications after surgery, including allergies to medications, bleeding in the eye, double vision, cataracts, glaucoma, and eye infection.

Written by Stephanie Brunner (B.A.)
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

• Additional
• References
• Citations