Retinal detachment refers to an emergency condition, wherein a layer of retina tissue gets detached from the layer of blood vessels that supplies it with nutrients and oxygen.
Retinal detachment deprives the oxygen supply to the cells of retina. If retinal detachment is not attended to, for prolonged periods, then it increases the vulnerability to permanent loss of vision in the affected eye.
Early diagnosis, detection and treatment for retinal detachment can save the vision and hence one should consult an ophthalmologist as soon as the warning signs appear.
Symptoms of Retinal detachment
Retinal detachment symptoms are as follows:
- Sudden onset of floaters or debris such as hairs, spots or strings that obstruct the field on vision and seem to float in front of the eyes
- A partial shadow or curtain in the visual field.
- Flashes of light in a single or both eyes may appear suddenly
Causes of Retinal detachment
The causes for retinal detachment are:
- Advanced diabetes
- Reduction of jelly-like vitreous matter present in the eye
- Presence of an inflammatory disorder
The process of retinal detachment
It can occur when the vitreous liquid leaks through a hole or a tear in the retina and collects beneath the retina. Retinal disorders and aging can cause thinning of the retinal walls. Tears and holes can develop in such areas. A sudden separation of vitreous from the retina causes tears which results in retinal detachment. On rare occasions, there may be leakage of fluid directly beneath the retina without a hole or tear.
When the liquid collects beneath the retina, it gets distanced from the layer of blood vessels that lie below it. This deprives the supply of blood to the affected areas of the eye, leading to ceasing of its functions and vision loss
Aging changes the consistency of vitreous humor and the liquid may shrink or may expand, thus causing it’s separation from the surface of retina. Such a condition is known as vitreous collapse or posterior vitreous detachment (PVD). When the vitreous separates and tugs on the retina with force, it can form a retinal tear. If left untreated, the tear can result in retinal detachment. Flashes of bright lights when the eyes are closed or the appearance of floaters are the visual symptoms of PVD.
Risks factors of retinal detachment are:
- An age of above 40 years
- A family history or personal history of retinal detachment in one eye
- Previous eye injury and/or surgery
- Extreme cases of myopia
Treatment of Retinal detachment
Surgical intervention is required for repairing retinal hole, tear or detachment. The correct treatment option is decided in consultation with ophthalmologist.
Surgery for retinal holes and tears:
If the retinal tear or hole has not progressed into detachment, the eye surgeon may decide to go for out-patient treatment to prevent retinal detachment and save the vision.
The available options are:
- Laser surgery: In laser surgery, the surgeon projects a laser beams through an ophthalmoscope which creates burns around the retinal tear. The resultant scarring ‘welds’ the retina to the tissues lying beneath.
- Freezing or cryopexy: In freezing, the surgeon employs extreme cold to freeze the retina around the retinal hole. After numbing the eye by an anesthetic, a freezing probe is applied directly over the defective part of retina. This process freezes the area around the tear which helps to attach the retina to the eye wall.
After this process one has to remain relatively immobilized for two weeks for strengthening the bond given by this procedure.
Surgery for retinal detachment:
The size, type and location of the retinal detachment determine the choice of surgical methods used to repair the retinal detachments. These procedures may be adopted in combination with laser therapy or cryopexy. Even though most surgeries are successful, sometimes a second treatment may be needed.
The procedures adopted are:
- Pneumatic retinopexy: In this, a bubble of gas or air is injected into the vitreous. The gas bubble swells over the next several days and seals the retinal tear by pushing it towards the detached area that surrounds the tear. It stops the new flow of fluid and absorbs the fluids already collected under the retina. The retina is thus able to reattach to the back wall of the eye. As per the location of the retinal detachment, one may have to hold his/her head in a particular position for many hours to hold the bubble in its place.
- Sclera buckling: It involves suturing a sponge or silicone rubber piece on the white of eye over the affected area. This silicone material binds the wall of the eye, rectifying the tugging of vitreous on retina. If the eye has several holes and tears with extensive detachment, the surgeon may encircle the entire circumference of the eye with scleral buckle like a belt. Normally the buckle remains for rest of the life.
- Vitrectomy: Under this procedure, the gel like fluid present in the eye-center is drained along with the tissues that are tugging the retina. Gas, air or liquids are injected into the vitreous cavity for reattaching the retina. This procedure may be combined with the sclera buckling.
Reattaching retina is not always successful. It may take several months after the eye repair, to have improved vision. Some may not recover.