The eye works like a camera. It has two parts, a lens and a film. The film layer lines the back wall of the eyes and is called the retina. There is an area of the retina responsible for the central vision called the macula.
Age-related macular degeneration (AMD) refers to specific age-related changes in patients 50 years and older. Wet age-related macular degeneration is characterized by the formation of undesirable abnormal new blood vessels. These blood vessels have a tendency to leak which decreases the quality of vision. Furthermore, if left untreated, these blood vessels may form scar tissue which leads to a permanent decrease in central vision.
In this case, there is scar tissue underneath the central vision which may limit vision, even with treatment. Wet AMD comes in a spectrum from those who have driving level vision upon being diagnosed to others who are legally blind. The treatments that are available improve vision by about 1-2 lines during the first year of treatment and then maintain vision for many years. Treatment results vary for each eye.
It is important to mention that patients with this condition who have lost some of their central vision need not worry about their peripheral vision. AMD does not affect the peripheral vision. Therefore, even patients who do experience worsening of macular degeneration are able to see, just not clearly in the center of their vision.
The treatments available are treatments, not a cure. This means that patients will continue to need treatments for many years. Treatments are typically initiated every 4 weeks. The eye is monitored for its response to the medication and the time interval between injections is adjusted appropriately.
All treatments for wet macular degeneration are administered by an intravitreal injection. An intravitreal injection is a safe in-office procedure in which a medication is injected into the vitreous cavity of the eye. This can be performed in a manner that causes minimal discomfort to the patient. Intravitreal injections are the only method available for the effective treatment of macular degeneration.
Patients will notice their vision is blurrier immediately following the procedure. It is also common for patients to see black spots that move when their eyes move for 1-2 days following the procedure.
Redness commonly occurs after the injection where the needle entered the eye. In some cases, the entire eye will become very red. The redness will resolve without additional treatment within 1-2 weeks and cause no permanent harm to the vision.
The eye is typically sore after the injection, but usually feels much better by the following day.
If the vision goes black immediately after the injection, this could be a sign that the eye pressure is too high. The vision will usually return on its own within a minute. However, this does require immediate attention from your doctor.
Patients who are experiencing a burning sensation immediately after the eye injection should make the staff aware.
Patients who experience a burning sensation after leaving the office may consider using preservative free artificial tear every 1 hour as needed for discomfort. It is important they wash their hands with soap and water and avoid touching their eye lashes.
The main risk of the procedure is the development of an infection called endophthalmitis. Fortunately, the risk of this infection is very low, occurring in approximately 1 in 3000 injections. The signs of infection are eye pain, sensitivity to light, and decreased vision. If it occurs, it typically occurs 3-5 days following the treatment, but may occur earlier or later. Patients with these symptoms need to contact their eye care specialist immediately. Patients can decrease their risk of developing an infection by avoiding rubbing, touching their eyes, or allowing water into their eyes for at least one week.
Most patients undergoing intravitreal injections find that the procedure is much more comfortable than anticipated and that the post-procedure discomfort is minimal.
The goal of treatment in wet AMD is three fold: maximize vision in the affected eye, prevent the development of wet AMD in the other eye, and early detection of wet AMD in the other eye should it occur.
Patients who have both eyes affected by wet AMD do not need to take eye vitamins. Patients with only one eye affected by wet AMD will benefit from taking eye vitamins. The Age Related Eye Disease Study Number 2 (AREDS2) vitamin decreases the risk of losing vision from macular degeneration by 25%. This formulation is different from a multivitamin. Taking a multivitamin plus lutein/zeaxanthin does not contain the same contents as an AREDS2 vitamin. Patients who regularly take a multivitamin may take an AREDS2 in addition if recommended by their doctor.
Eating green leafy vegetables and fish on a regular basis decreases the risk of experiencing worsening macular degeneration. A diet rich in omega-3 vitamins may further decrease the risk of macular degeneration worsening. Using polarized sunglasses while outside for extensive amounts of time can decrease retinal damage from significant sun exposure. Maintaining a healthy weight can also decrease the risk of macular degeneration worsening.
Smoking increases the risk of macular degeneration worsening by 3 times compared to a non-smoker. Discontinuing smoking decreases this risk by 50%.
Monitoring vision is recommended for patients who have one eye with dry macular degeneration. Monitoring with an Amsler grid dramatically decreases the risk of vision loss from this condition. New distortion or blurriness discovered on an Amsler grid may be a sign of wet macular degeneration. Early detection and treatment of wet AMD can significantly improve visual results with treatment.
An Amsler grid should be used to check each eye individually at a reading distance. Patients are instructed to look at the black dot in the center of the grid paper. Patients who notice new distortion or missing lines may be experiencing a conversion to the wet form of macular degeneration (see example below).