What is AMD?
AMD (age-related macular degeneration) is a degenerative disease of the macula or central area of the retina and greater visual sensitivity. It affects millions of people and represents the leading cause of blindness in people over 65 years of age in industrialized countries.
This pathology causes a progressive deterioration of the retinal pigment epithelium (the layer that covers the retina and nourishes it) and of the macula cells (where a greater number of cones or photoreceptors responsible for visual acuity and colour discrimination are concentrated). As a consequence, there is a gradual loss of central and detailed vision.
There are two types of AMD,God Service Eye Clinic taking into account that the same patient can go from one to the other:
- Dry or atrophic AMD: It is the most prevalent form (around 85% of cases) and is characterized by a slow and progressive evolution. It occurs as a result of the accumulation of debris (yellowish deposits or drusen), which atrophies the macular area.
- Wet or exudative AMD: Although it is less common, its progression is faster and it usually has a worse visual prognosis. In this form of AMD, a vascular membrane grows under the retina, due to the appearance of new abnormal and very fragile blood vessels, which bleed and lose fluid, severely compromising vision.
Why does it occur?
Age is the main risk factor for AMD, which does not usually appear before the age of 50-60 and whose incidence increases over time.
To ageing we must add genetic predisposition since it has been shown that genes have more weight than previously believed in the disease: it is estimated that 50% of the risk of AMD is hereditary and that the probability of suffering from it is between 3 and 6 times higher if you have a first-degree affected relative.
Finally, we must also consider the influence of environmental factors, the main one being tobacco, which multiplies by 5 the chances of developing AMD.
- Bad eating habits
- Arterial hypertension
- Circulatory problems
- Direct and prolonged exposure to the sun
People with AMD progressively lose central and detailed vision, reducing its sharpness and being able to see blurred or “cloudy” in the middle of the visual field. This causes difficulties in recognizing faces, reading, writing, driving, sewing or performing different precision tasks.
However, it allows you to maintain a certain autonomy when driving around the house or on the street since peripheral vision is preserved.
Other characteristic symptoms of AMD are:
- Distortion of images / “wavy” perception of straight lines (metamorphopsia)
- Perception of a fixed black spot in the middle of the visual field
- Alteration in the perception of the size of objects
- Alteration of in-depth perception and difficulty calculating distances
- Difficulty distinguishing colours
It must be taken into account that AMD is a generally bilateral disease, that is, it affects both eyes, although it can do so asymmetrically.
When it comes to the wet form of the pathology, its progression is much faster and can manifest itself in just days or weeks.
How can it be prevented?
AMD cannot be prevented because, to a large extent, it is linked to the natural ageing process and genetics. However, it is up to each patient to pay attention to their family history – genetic predisposition tests can be performed – and to focus on environmental risk factors: not smoking, and following a balanced diet rich in antioxidants and omega-3 fatty acids. , avoid a sedentary lifestyle, protect yourself from the sun…
On the other hand, periodic eye check-ups are essential, especially after the age of 50, to detect the disease early, since at the beginning it may cause few symptoms.
A good complementary measure to these reviews is self-monitoring that the patient can perform from home using a simple test, the Amsler grid. This test, which can be requested by the optician or ophthalmologist, allows you to detect whether straight lines look crooked or distorted (a characteristic symptom of wet AMD).
For the same purpose, the patient can also cover first one eye and then the other and pay attention to the door frames, tiles, railings… or read the same text daily, from the same distance, to notice any anomaly and attend to it. case to the specialist.
Wet AMD can be treated effectively thanks to the development of new antiangiogenic drugs, which are injected into the eye (intravitreal injections ) and act by inhibiting vascular endothelial growth factor (anti-VEGF) to prevent the formation of new abnormal blood vessels.
In this way, they allow the disease to be stopped and the majority of patients to be able to maintain and even recover their vision. The earlier treatment is started, the better the visual prognosis will generally be.
Regarding dry AMD, there is currently no effective treatment, although there are studies that are testing the application of intravitreal injection drugs to control its progression in certain patients.
For the moment, an option that can help slow down dry AMD is the prescription by the ophthalmologist of certain antioxidant vitamin supplements, which help protect the retina