Macular Degeneration: Types, Symptoms And Treatment
Central vision, which depends on an ocular structure called the macula, is what allows us to focus on details and carry out daily activities such as reading a book, driving, or even recognizing a person’s face. This type of vision is what is affected when a disorder known as macular degeneration occurs, a disease that affects older people more and ends up causing vision loss.
In this article we explain what macular degeneration is, what are its two most common forms and the symptoms associated with each of them. In addition, we tell you what the main risk factors are that lead to the appearance and development of this eye disease, as well as the treatments currently available.
Macular degeneration, also called age-related macular degeneration, is an inherited neurodegenerative eye disorder that gradually affects central vision, which depends on the macula and the one that provides us with the visual acuity necessary to carry out tasks such as driving, reading or recognizing a person’s face.
The macula is a tiny part of the eye, in the form of a yellowish spot (due to the high concentration of two pigments that give it that color), which is located in the central area of the retina. It is made up of the fovea, located inside the macula and responsible for the perception of colors; and the foveola, located within the fovea, is what allows us to have maximum visual acuity.
In macular degeneration, as its name indicates, There is a progressive deterioration of the macula, which is what allows us to perceive details and movement which is why people who suffer from this condition end up suffering a significant loss of vision, especially related to fine details, whether close up or far away.
This loss of central vision entails a series of negative consequences in the daily lives of people who suffer from this condition, whose age is generally advanced. Macular degeneration is considered one of the main causes of blindness and low vision, and at the moment there is no known cure.
Currently, this disease affects 1.5% of the population, and if only people over 50 years of age are considered, the prevalence increases to 5.3%. Next, we are going to see what the two main forms of macular degeneration consist of.
Types and their symptoms
There are two types of macular degeneration: dry, which is the most common of the two; and wet, less frequent but more serious. Let’s see in more detail what each of them consists of.
Dry or atrophic macular degeneration
Dry macular degeneration is the most common type, making up 85% of all cases. Photoreceptors in the macula (light-sensitive cells) and retinal pigment epithelium deteriorate progressively, and deposits or extracellular waste products called drusen are formed.
The presence of drusen in the retina is relatively normal after the age of 45, and very common in people over 65 years of age; However, an increase in their number and size is usually the first sign of possible macular degeneration. The result is blurred or spotted vision and loss of central vision.
Dry macular degeneration evolves slowly over time and is developed in three stages:
Early stage
Presence of small and medium sized drusen, without loss of vision or symptoms
Middle stage
The person has medium and large drusen, and blurred vision may appear. spots in the center of the visual field Sometimes the subject may need more light for tasks that require focusing on details.
Presence of multiple drusen deposits, destruction of the retinal pigment epithelium and the photoreceptor cells of the macula. At this stage, blurred vision occurs and, over time, vision loss.
Wet or exudative macular degeneration
Wet or exudative macular degeneration is the less common form (around 15% of cases) but more serious. It happens when blood vessels (which make up the neovascular membrane) begin to grow abnormally behind the macula, causing fluid and blood to drip. These exudations end up causing scars and, consequently, macular damage.
In this form of macular degeneration, loss of central vision occurs rapidly. Its development does not occur in stages, as occurs with the dry form, and the damage is more severe. The most common initial symptom is seeing distorted straight lines s, as if they had a wavy silhouette. Vision may become blurred or lost completely in a very short period of time (days or weeks).
There are two subtypes of wet macular degeneration: occult, which occurs due to fluid spills and the growth of new blood vessels under the retina, and causes milder vision loss; and the classic one, whose severity is greater in terms of vision loss and occurs because the growth of blood vessels and scarring generates large debris, responsible for the injury to the macula.
Risk factor’s
The main risk factor for macular degeneration is age, since for people over 50 years of age the probability of suffering from this disease increases considerably. Other relevant factors that may increase the risk of developing this disorder are the following:
1. Family and genetic history
Macular degeneration is hereditary and several genes have been identified that could be involved in the development of the disorder, so The risk increases if you have a direct relative who suffers from the disease
According to research, People who suffer from obesity have a higher risk of moving from the early and middle stages to the advanced stage of the illness.
3. Smoking
Regular exposure to cigarette smoke increases the risk of developing the disease, and smoking patients respond worse to treatment
4. Race
Caucasian people are at higher risk for muscle degeneration compared to other races, such as African Americans.
5. Cardiovascular diseases and hypertension
There is a relationship between diseases that affect the heart or hypertension and macular degeneration.
6. Sex
Women are more likely to suffer from macular degeneration That men.
Treatment
Currently, there is no treatment that can prevent the vision loss caused by dry macular degeneration when it reaches the most advanced stage. However, yes it is possible to slow or prevent the disease from progressing from the early phase to more advanced stages through the use of high doses of antioxidants and minerals such as zinc, according to the indications of the National Institute of Ophthalmology.
To treat wet macular degeneration there are several therapeutic alternatives: laser surgery, used to destroy the blood vessels that cause macular damage; photodynamic therapy, which consists of injecting a substance into the body and then activating it using light that illuminates the blood vessels of the eye; and eye injections with anti-VEGF drugs, which eliminate growth factors that promote the development of abnormal blood vessels.
However, macular degeneration and vision loss associated with this disease can continue to progress, even when receiving treatment. For now, There is no known cure or completely effective treatment but research is still being carried out in this regard.
