Description
Wet age-related macular degeneration (AMD) is a chronic disease of the eye that leads to blindness if it does not receive treatment.
If an eye receives treatment for wet macular degeneration, further vision loss can be prevented. The vision can usually be improved, or at the very least prevented from getting worse.
Wet macular degeneration is caused by abnormal blood vessels that grow underneath the retina, in a space called the choroid.
These abnormal blood vessels are new and are not supposed to be there (termed "neovascularisation").
The retina is the part of the eye that receives all the visual images and converts them to a signal that the brain can understand. If the retina is damaged, the brain can’t understand the images that the eyeball receives from the outside world.
The macula is the part of the retina that is responsible for your central vision. The retina is located inside the eye, in its posterior portion.
Dry macular degeneration occurs before wet macular degeneration. Dry macular degeneration leads up to wet macular degeneration. In dry macular degeneration, the layers of the retina begin to die off in a patchy manner. Later on in the disease process, abnormal blood vessels begin to grow near these abnormal patches. This is the wet stage of macular degeneration.
If left untreated, the abnormal blood vessels in wet macular degeneration begin to leak fluid and bleed, as well as form scar tissue. All of these abnormal changes are what causes the retina to malfunction, leading to blurry vision. If left untreated the blurry vision can become permanent due to scarring of the retina.
Diagnosis
The diagnosis of wet macular degeneration is made by using three pieces of information: a dilated eye examination by your retina specialist, and two tests called fluorescein angiography (F.A. for short) and optical coherence tomography (O.C.T. for short). Using these three pieces of information in combination allows the retinal specialist to make the diagnosis of wet macular degeneration with a high degree of certainty. While examining your eye, your doctor will be looking for signs of wet macular degeneration that he has learned to appreciate after having examining tens of thousands of eyes with macular degeneration.
Treatment
Wet macular degeneration is treated by a medicine that causes the abnormal blood vessels to die off. The medicine works by stopping a molecule called VEGF (vascular endothelial growth factor). VEGF causes the abnormal blood vessels to grow. By stopping VEGF, the blood vessels won’t grow. The category of medicines that stop VEGF are called anti-VEGF drugs.
There are five anti-VEGF drugs that can be used to treat wet macular degeneration: Avastin, Eylea, Lucentis, Beovu, and Macugen. Avastin is the first line drug for most retinal specialists in the world in the treatment of wet macular degeneration. No other drug has been proven to treat wet macular degeneration better than Avastin. Across the USA and the rest of the world, Avastin is used more frequently than any of the other anti-VEGF drugs. Because of those reasons, Avastin is also the most commonly used drug that we use to treat macular degeneration. Occasionally, certain types of eyes may be best suited for treatment with the one of the four drugs other than Avastin. If that is the case, we will use the best drug for those particular circumstances.
The anti-VEGF drugs are used to treat wet macular degeneration by being injected into the eye. The eye is numbed up with a lidocaine anesthetic so that it will not feel pain during the injection. The numbing anesthetic takes less than 10 minutes to take effect and lasts up to an hour. In order to minimize discomfort, the needle that is used is one of the smallest needles used in all of medicine. The injection is done on the bottom outside corner of the white of the eye. The site of the eye where we do the injection has no parts that could be damaged by the injection. The actual injection takes only two seconds.
The medicine that is injected is a clear liquid so it won’t blur the vision. In addition to the anesthetic, a betadine antiseptic is used to kill off any bacteria on the eye before the injection. After the injection, the eye is rinsed off to remove any traces of the antiseptic and anesthetic.
The effect of the anti-VEGF drugs begins to wear off after a month. In order to prevent VEGF from re-accumulating and to prevent the abnormal blood vessels from coming back and causing more damage, anti-VEGF drugs need to be injected again after they wear off.
Well over 99% of injections are tolerated without any side effects. The most common symptom after an injection is slightly blurred vision that returns to normal the next day. This is normal. Also, the eye may produce tears more than usual . This is normal as well, and will resolve by the next morning. Sometimes the eye has a gritty or foreign body sensation, which can be relieved by using over-the-counter lubricant eye drops. The eye rarely will have a slight stinging or burning sensation. This is usually due to the betadine antiseptic. If that occurs, a combination of over-the-counter lubricant eye drops and over-the-counter pain medication (such as Tylenol or Aleve) works best. An ice pack applied over the eye when the eyelids are closed also helps relieve the discomfort, which resolves by the next day.
Finally, very rarely some patients can develop an allergic-type inflammatory reaction to the drug, but this is restricted to the inside of the eye only and does not involve any other part of the body. This usually clears up on its own within a week or so. The main symptom of this type of reaction is blurry vision that doesn’t clear up a day or two after the injection. If your vision gets progressively blurrier and blurrier more than a day after the injection, you should contact the eye clinic. You may be experiencing an inflammatory reaction. We would like to examine the eye to confirm this and also to make sure there is no infection. The likelihood of getting an infection is extremely rare (about 1 out of 3000). The main symptom of an infection is progressively blurry vision more than two to three days after an injection along with some degree of eye pain. If you develop progressively blurry vision more than two days after an injection, or worsening eye pain more than two days after an injection, please give us a call.
Many patients with wet macular degeneration have the condition in both of their eyes and require injections in both eyes. For those patients, it is preferable that the injection be performed on separate visits. There are many reasons for this. The first is that some patients find the thought of having both eyes treated on the same day to be too stressful. Another reason is that in case the vision gets blurry for some reason due to the injection, the other uninjected eye can then be relied upon until the vision clears up in the injected eye.
Some patients have wet macular degeneration in one eye and dry macular degeneration in the other. For those patients, the doctor will examine the eye with dry macular degeneration at least about once every three months to make sure that it has not developed wet macular degeneration in the meanwhile. It is important that the eye with dry macular degeneration be checked this often because it is at a very high risk of converting to the wet macular degeneration stage. Of course, should the patient notice any new sudden changes in the eye with dry macular degeneration in between their scheduled appointments, they should contact the office to let us know.
It is important to understand that once wet macular degeneration is diagnosed, the disease will continue to worsen and lead to blindness unless it is treated appropriately. One cannot hope that the vision will just stay the way it is without receiving the proper treatment. Unfortunately, with wet macular degeneration there are just two choices: (1) get better vision in the long run with proper treatment, or (2) become blind. Unfortunately this is how the disease works. We are fortunate to live in an age where we have effective treatments that work. Just less than fifteen years ago, patients with wet macular degeneration usually did not even have a choice: almost all of them went blind despite the doctor’s best efforts. Nowadays, the main barrier to patients getting better vision with wet macular degeneration is keeping up with scheduled appointments.
Following Up
When treatment is begun for wet macular degeneration, the first goal is to try to inactivate the abnormal blood vessels. During this first phase of the treatment, the medicine is injected into the eye once every month. It is absolutely important that this regimen is followed. If the medicine is injected less frequently while the abnormal blood vessels are still active, they can grow back and bleed leading to scarring and permanent vision loss. If, for some reason, an appointment for a scheduled injection is missed, another appointment should be obtained as soon as possible afterwards or the vision may get worse permanently.
The injections are repeated monthly until the doctor is sure that the abnormal blood vessels are inactivated. This is ensured by examining the eye and checking F.A. and O.C.T. tests after every three injections. Once the abnormal blood vessels are inactivated, the injections can then be done less frequently. On average, the abnormal blood vessels are inactivated after the eye receives a total of seven injections. This is just an average. Some patients get well faster and some take longer to respond to treatment. The retina doctor will make the ultimate determination about when the abnormal blood vessels are truly inactivated. Once the abnormal blood vessels are inactivated, the next goal is to prevent them from reactivating or coming back. The medicine needs to be continually administered in order to prevent them from reactivating. If the injections are stopped altogether after the abnormal blood vessels are inactivated, it is only a matter of time before the abnormal blood vessels reactivate. Fortunately, it does not take as much effort to keep the abnormal blood vessels from coming back as it does to inactivate them in the first place. For this reason, the injections are continually administered, but they are gradually done less and less frequently. For example, the injections are initially spaced out to being given once every six weeks. Then, they are spaced out to once every seven weeks. Then they are spaced out to once every 2 months, and from there on gradually to once every 3 months, or only about four times a year or less. This approach is the best to treat wet macular degeneration and also to minimize the risk of vision loss. It is important to understand that wet macular degeneration is a chronic disease that has no permanent cure. It can only be suppressed. For this reason, some amount of medicine should always be in the eye in order to prevent the disease from coming back and damaging the vision.
Some retina specialists use laser to treat wet macular degeneration. Studies show that this approach does not give as good vision as the injections. However, some people simply cannot tolerate the injections. If that is the case, do not give up on your doctor. Simply express that you no longer want to receive the injections but would like to request treatment with the laser, all the while realizing that the vision won’t be the absolute best that it would be with the injections. Remember, some treatment is still better than no treatment at all.
Besides receiving treatments in the office, the treatments may be helped by taking the AREDS2 formula vitamin supplement. Also, stopping smoking is extremely beneficial in helping to control wet macular degeneration. Finally, some recent studies suggest a possible link between aspirin use and wet macular degeneration. Although the findings are a cause of concern, there is simply not enough evidence at this time to recommend stopping aspirin if you have wet macular degeneration. Besides, aspirin has been show to have numerous other beneficial effects in reducing certain problems with heart attacks, strokes, and cancers.
This handout contains the most up-to-date information available on wet macular degeneration. Your doctor receives daily updates on new breakthroughs in wet macular degeneration. The contents of this handout are updated very frequently as new findings come out. There is a lot of misinformation out there about wet macular degeneration. If you have heard something from someone that conflicts with the information presented, keep in mind there is a chance it might be outdated or it might be biased by financial incentives.