Learn about symptoms of macular degeneration that are often not as noticeable or occur less frequently.
People with AMD are usually diagnosed during a routine eye exam when the eye doctor sees small white spots in the retina called drusen. Or, if they have advanced AMD, a person may notice a dark area or distortion in their central vision. However, there are other symptoms of AMD that are less noticeable or occur less commonly, but are worth knowing about.
Delayed Dark Adaptation
One common symptom that’s harder to notice is that it takes longer to see in the dark, which is called delayed dark adaptation. This occurs when the retina takes longer than usual to adapt when switching from a bright to a dark environment. For example, it would be more difficult to see the seats in a dark movie theatre immediately after coming in from the bright sunlight. The low light vision may then return very slowly over about 30 minutes.
Patients have also complained of flashing lights in the central vision. This is more common in people wet AMD. It can occur when new blood vessels or scar tissue is tugging on the retina. It is important to differentiate this from flashing lights in the side vision, which, when associated with new floaters or a “curtain” blocking the side vision, can be a sign of a different disease: retinal detachment. For patients with symptoms of retinal detachment, it is necessary to have an eye exam as soon as possible so that treatment can be given promptly.
Dark or Black Spots on White Walls When Waking Up
Some patients will notice abnormalities in central vision only when looking at a white wall. For example, upon waking up in the morning and looking at the ceiling, some have complained that they see dark areas. This can be caused by areas of wet macular degeneration or areas of retinal atrophy, when the vision-sensitive cells, the photoreceptors, die in a region of the macula.
People who lose some central vision may also have visual hallucinations, called Charles Bonnet syndrome. This represents the brain filling in images when it no longer receives visual input from part of the retina. The images can be patterns like wallpaper, and sometimes even animals or people. Patients are often reluctant to bring this up because they think it suggests they are “going crazy.” They should be assured that it is not a sign of craziness; just the brain getting “bored” when it no longer receives input from that part of the retina. The hallucinations are rarely threatening, and most people can accept them once they understand why they occur.
Subtle Distortions in Vision
One sign of drusen in early AMD can be subtle distortions in central vision. For example, a straight line like a door frame may appear to have a small curved area. This is because drusen cause slight retinal elevations, causing light from a straight line to “land” on the wrong part of the retina.
Noticeable Symptoms When One Eye is Closed
Sometimes patients will only notice vision changes in AMD when they close one eye, for example when applying makeup. When the “good” eye is closed, the impaired central vision in the eye with advanced AMD is noticed for the first time. This is because the good eye has been compensating for the advanced AMD eye. That’s why it’s important for patients with early AMD (drusen) to check vision in each eye separately by covering one eye at a time, at least once a week.
Once again, the most common symptoms of advanced AMD are central vision distortion or blank spots leading to difficulty reading, driving, seeing the TV, or recognizing faces, but other, less common symptoms outlined above can also occur.