Retinal detachment and its symptoms

What is a retinal detachment (RD)?

Retina detachment signifies, in a general sense, separation of the retina from its normal position. 

What are the types of retinal detachment? 

There are usually three types of retinal detachment, with the fourth being a combination of the first three. 

1. Rhegmatogenous retinal detachment (RRD) - the most common type that occurs due to a retinal or a break in the retina, allowing vitreous fluid to move into the sub retinal space and separate the retina from its normal position. These are usually managed by simple surgical interventions such as a scleral buckle (a band placed on the outside of the eye) or by vitrectomy. 
2. Tractional retinal detachment (TRD) - Usually seen in patients with diseases such as diabetic retinopathy, these usually occur due to forced pulling in the retina due to growth of fibrous tissue inside the eye. They do not have a hole in the retina. Management of these detachments usually requires vitrectomy to release of these 'tractional' forces. 
3. Secondary or serous retinal detachment - usually occurs, as the name suggests, due to some other reason inside or outside the eye. This can be from a benign growth in the eye, to cancer somewhere else in the body. Management includes treatment for the primary condition.  

What are the symptoms and signs of retinal detachment that may alert you to a possible problem?

• "Floaters" - Most of us have a few floaters that we either learn to ignore, or they disappear after some time. But when these floaters suddenly appear, they can be a potential sign that you should preferably undergo a retinal evaluation soon. They are better appreciated against light backgrounds, for e.g. a white wall. 
• "Flashes of light" - These are typically seen in dark rooms, or when the eyes are closed. Flashes with eyes open may not be an ideal sign of some damage to the retina. 
• "A falling curtain" - Some people complain that they notice a falling curtain when a retinal detachment is progressing fast. Usually, you will notice the curtain increasing in height from below in case you have a retinal detachment in the upper part of the eye, which can progress rapidly. An inferior retinal detachment takes a longer time to reach the central part of the retina, the macula, due to gravitational forces.  
• "Decrease in vision" - If your retinal detachment has reached the central part of the retina, i.e. the macula, your vision will be affected. You may either notice 'shadows' or 'screens'. People describe this feeling in various other ways. Such visual impairment usually occurs when some one has a superior retinal detachment. 
• It is also important to evaluate each eye separately. Sometimes, the good eye overrides the symptoms in the other eye and a person may miss the symptoms. It is recommended that you evaluate yourself to be certain by closing one eye (with the palm of your hand gently held in front of the eye to be closed - DO NOT PRESS THE EYE) and looking with the eye to be evaluated. 

There are other predisposing factors that are usually considered in terms of likelihood of development of retinal detachment. These may include:

• High myopia
• Trauma to the eye
• Cataract surgery
• Injections in the eye

What to do when you have any of the above symptoms?

1. Symptoms happening for the first time - Preferable to get your retina evaluated soon. 
2. Repeat symptoms - Preferable to go by what your physician has advised you earlier. If you have been told to come back for a check if any of the symptoms occur, it is best to follow their advice. 
3. Recent surgery in the eye or treatment such as an injection - You should preferably go to the specialist soon. 
4. If you are a high myope - A routine yearly retinal examination is a must. If your doctor wants you to return sooner, do follow that advice. 
5. Patients with diabetes or other vascular issues such as venous occlusions may develop tractional retinal detachments. These may initially appear without much symptoms, or they may be associated with flashing lights. Usually, these retinal detachments are associated with the retinal disease such as diabetic retinopathy that may have caused reduction in vision by itself. Hence, symptoms may not be a good way of self evaluation.

What are the chances of developing RD in the other eye, when one eye is affected by it?

When someone develops a retinal detachment (RD) in one eye, the treating physician usually says that the concerned person should be aware of the chances of developing a similar episode in the other eye. Usually, the symptoms and signs are explained to the patient in detail. But what are these chances of developing retinal detachment in the other eye?

Many studies have been done since many decades to figure out the chance of developing a similar problem in the other eye. Since years, those affected have been told that the chance generally is about 8%. In a recent study from Denmark of 11451 patients with rhematogenous RD (RRD - the most common type of RD), the authors concluded that the other eye has a 100 times greater risk of developing RRD on the second eye, and this risk increases with male patients and those who have had cataract surgery, though it decreases with age.

In another study in Scotland over 2 years, the other eye developed RD in about 7.3% of patients, with RD being more commonly seen in cases where the patient had undergone cataract surgery before, and/or in patients with high myopia. They also found that considering the patient was now more aware of the symptoms of RRD, they presented to the hospital earlier than before.

Generally, in most cases that are not associated with cataract surgery or trauma, the other eye is found to have predisposing features such as a retinal hole or tear, or some 'weak' spots in the retina, usually described as lattice degenerations. These are the usual causes for the development of RD. When found, and after assessing the risk for RD development, the treating physician usually recommends treatment for these spots with laser photocoagulation. 

In essence, all of us should be aware of the symptoms, since RD can potentially happen to anyone. Most of the 'weak' spots are not symptomatic, and hence a good retinal evaluation in predisposed individuals such as high myopes, or in those over 40 should be considered. Those with a direct family history of retinal detachment should also consider retinal evaluation, since such predisposing factors are passed through generations. And if you develop any of the symptoms mentioned above, or do not feel about your sight or the eye, do consider checking with a retina specialist as soon as you can.