What is retinal detachment? How do you treat it?
The retina is the neurosensory tissue that lines the back wall of the eye. Like the film in a camera, the retina is responsible for creating the images that one sees. The center of the retina is called the macula and is the only part capable of fine detailed vision, i.e. reading vision, recognizing faces, etc. The remainder of the retina, the peripheral retina, is for side vision. The retina outside the center of the macula, which makes up more than 95% of the retina, is not capable of the fine detailed vision.
When the retina detaches, it separates from the back wall of the eye and is removed from its blood supply and source of nutrition. The retina will degenerate and lose its ability to function if it remains detached. Central vision will be lost if the macula remains detached. The causes of retinal detachment can be divided into three main categories:
1.. Rhegmatogenous retinal detachment
2.. Exudative retinal detachment
3.. Traction retinal detachments
Of the 3 types of retinal detachment, rhegmatogenous retinal detachment is the most common, deriving its name from rhegma, meaning rent or break. Vitreous fluid enters the break and separates the sensory retina from the underlying retinal pigment epithelium or choroid resulting in detachment. The choroid is a vascular membrane containing large branched pigment cells sandwiched between the retina and sclera.
Exudative retinal detachments occur when subretinal fluid accumulates and causes detachment without any corresponding break in the retina. The result is usually tumor growth or inflammation.
Tractional retinal detachment occurs as a result of adhesions between the vitreous gel and the retina. Mechanical forces cause the separation of the retina from the retinal pigment epithelium without a retinal break. Advanced adhesion may result in the development of a tear or break. The most common causes of tractional RD are proliferative diabetic retinopathy, sickle cell disease, advanced retinopathy of prematurity, and penetrating trauma.
The warning signs of retinal detachment are:
a.. Light "flashes" and blurred central vision.
b.. The presence of a "veil," or shadow, over part of the field of vision.
c.. Large "floaters" or spots that travel across the field of vision, possibly indicating a partial retinal detachment or of clumped vitreous collagen fibers.
You should report any of these warning signs to your ophthalmologist immediately. The best chance for restoring sight relies on prompt treatment.
Retinal detachment treatment
Small holes and tears and very limited retinal detachments are usually treated with laser photocoagulation or cryopexy. These procedures are usually administered in the physician's office. Laser photocoagulation is a procedure whereby pinpoints of laser light are used to create tiny burns around a small hole to "weld" the retina back to the wall of the eye. Cryopexy is a similar procedure which, instead of using heat, freezes the area around a hole back into place.
Extensive detachments are treated surgically with a procedure called scleral buckling. In scleral buckling, a tiny synthetic band is implanted on the outside of the eyeball to gently push the wall of the eye against the detached retina. If necessary, a vitrectomy may also be performed to treat more severe cases. During a vitrectomy, the diseased vitreous is surgically removed and an artificial substance is inserted to push the retina back against the eye wall.
If treated early, sight is usually improved in 80% of the patients with the first treatment. In other cases, more treatments are necessary to remedy the damage.
