Macular degeneration: what it is, symptoms, causes, treatment

By Cristiano Antonino On Apr 18, 2023

Aging can be the cause of various health-related ailments, more or less serious. Among these is macular degeneration, a pathology linked to the eyes which, however, can also involve younger people

What is macular degeneration

We talk about macular degeneration when we are faced with a retinal disease that causes an alteration or a reduction in visual function in the central part of the retina itself.

This type of pathology compromises visual functionality at the level of the central visual field, the one occupied by the macula.

Macular degeneration is a condition that usually develops with aging

Over the years, the eye ages just like the rest of the body, which is why, starting from a certain age, the visual functions can be compromised in a physiological way.

In this case, we speak of age-related macular degeneration, or AMD.

In the eyes, aging causes the retinal cells to die, which in turn affects the macula until it loses its characteristics.

The macula

The macula is a central portion of the retina, the layer of tissue that lines the back of the eye, and is involved in the functioning of central vision.

In practice, the macula serves to focus the gaze in the center of the visual field, and is responsible for recognizing the details that are right in front of us.

A healthy macula is therefore essential for vision, in particular for all those operations that require focusing on details (such as threading a needle, reading, recognizing road signs).

Types of macular degeneration

As we have said, macular degeneration is a physiological condition that develops with age, even if its progress can be more or less rapid and compromise vision in different ways depending on the affected patients.

There are also two types of macula degeneration related to aging: dry and wet.

Dry macular degeneration

Also called atrophic or non-exudative, it represents the main form of AMD, affecting between 85 and 90% of patients.

It consists in the progressive thinning of the central retina due to a poor nutrient supply from the capillaries: the photosensitive nerve cells die, the retina atrophies and a scar forms on the macula which appears like a “geographical map”.

Wet macular degeneration

This type of degeneration, also called wet or exudative, affects between 10 and 15% of patients with MSD but is also the most serious.

It develops much more rapidly than the dry one and is caused by the formation of new capillaries in the subretinal neovascular membrane.

However, these blood vessels are harmful because they have a very fragile wall and allow the plasma to penetrate more easily.

When they break, the leakage of blood causes retinal hemorrhage that collects under the macula, lifting it.

If the haemorrhages heal, vision can be compromised even very quickly.

Both types of macular degeneration therefore lead to lesions of the macula called drusen, i.e. waste deposited under the retina that can calcify.

When they develop, drusen are asymptomatic and do not affect vision, but depending on the degree they represent, they can have more or less serious consequences on vision. In any case, they can be identified through a fundus examination.

Juvenile macular degeneration

Macular degeneration does not only affect with age, but in some cases – albeit rarer – also younger people, even children.

However, these are hereditary retinal diseases, which can already arise in childhood or in adulthood.

There are several pathologies that trigger macular degeneration in young people, such as:

Stardardt disease: also called Stardardt maculopathy, it usually appears in the first twenty years of life and is caused by the mutation of the ABCA4 gene which involves the accumulation of waste material in an outer layer of the retina called the pigment epithelium
Best’s disease: a parent transmits to his child the mutation of the VMD2 gene, which in normal situations regulates the transport of some substances in the retina
juvenile retinoschisis: also called X-linked retinoschisis, it affects only young men and is characterized by a separation of the retina into two layers.

Symptoms of macular degeneration

At an early stage, the disease may cause no symptoms.

Although it generally affects both eyes, it can happen – especially in the early stages – that only one is affected and for this reason it can be more difficult to notice the degeneration, as the unaffected eye compensates for the low vision of the other.

Also, a distinction can be made between dry and wet symptoms, although many are common.

Among these we find:

reduction in central vision
fuzzy reading
scotoma (black spots in the field of vision)
metamorphopsia (distorted vision of objects)
photophobia (sensitivity to light)
inability to focus on people’s faces
need light for near activities
difficulty transitioning from dark to light

Symptoms of dry macular degeneration

As regards instead the specific symptoms of the different types of MSD, in the dry one there is a general decrease in vision, with blurred central vision and the presence of a blind spot in the visual field which widens over time making it increasingly difficult to carry out daily actions such as drive or read.

Symptoms of wet macular degeneration

In the case of wet AMD, on the other hand, the progression of the disease is much faster and it is easy to notice because vision is immediately compromised, in particular central vision which is lost rather quickly.

Those affected by wet-type macular degeneration may also complain of a blurred vision of the shapes, which appear distorted or irregular.

Rarely, macular degeneration leads to total blindness, since it does not affect the entire retina but only its central part.

For this reason, it is possible that peripheral vision is maintained but, in the more advanced stages of the disease, central vision is completely compromised.

Causes of macular degeneration

It is precisely natural aging that causes senile macular degeneration: not everyone is affected in the same way, but certainly people over 60 are the category most at risk.

But age alone does not appear to be the only cause of macular disease.

Risk factors

Among the risk factors that, in addition to age, can cause macular degeneration we find:

obesity
smoke
diabetes
sedentary lifestyle
alcohol abuse
belonging to the Caucasian population
masculine gender
prolonged and unprotected exposure to UV rays
hypertension
diet low in vitamins and fatty acids
high cholesterol
inheritance with affected first-degree relatives

Diagnose macular degeneration

After the age of 40 it would be important to have your eyesight checked regularly.

The eye examination is in fact the main examination to identify any eye disorder, including maculopathies.

To analyze the macula, therefore the central part of the retina, the ophthalmologist carries out an eye fundus examination with an ophthalmoscope: thanks to this instrument, it is possible to identify the drusen, the lesions caused by waste deposits, which appear yellow .

Once macular degeneration has been diagnosed through the identification of drusen, its evolution can be monitored with a very simple test called the Amsler grid: the patient must observe a series of straight lines that may appear distorted or not visible.

In some cases, moreover, specific tests are carried out, in particular when wet macular degeneration is suspected:

OCT, i.e. a non-invasive computerized optical coherence tomography, which allows you to obtain scans of the cornea and retina
fluorescein angiography, which consists in the injection of a contrast liquid that reaches the blood vessels and highlights their abnormalities

How is macular degeneration treated?

Treatment for age-related macular degeneration depends on the form in which it occurs.

In the case of the dry one, in fact, there is no cure, but one can only intervene to slow down its progression.

In this case, therefore, the lifestyle is improved, by stopping smoking, drinking alcohol, practicing physical exercise and consuming healthy and varied foods.

In some cases, supplements are used, for example based on lutein (recognized as valid allies for eyesight) or vitamins A and E, anti-oxidants and mineral salts, but it is always good to check with your doctor before taking them because opinions on the benefits are mixed.

The wet form, on the other hand, can be treated in different ways. Among the most common therapies we find:

photodynamic therapy, applied by laser which allows the selective occlusion of new capillaries (only the harmful ones)
intravitreal injections, through the use of anti-VEGF drugs, i.e. drugs that inhibit the proliferation of new blood vessels in the retina

Macular degeneration is a disease that affects the macula, the central part of the retina, and which can compromise central vision.

In most cases it is associated with aging and lifestyle can greatly influence its progression.

What Is Maculopathy, Or Macular Degeneration

What Is Macular Pucker And What Are The Symptoms

Macular Degeneration: Faricimab And The New Therapy For Eye Health

Red Eyes: What Can Be The Causes Of Conjunctival Hyperemia?

Autoimmune Diseases: The Sand In The Eyes Of Sjögren’s Syndrome

Corneal Abrasions And Foreign Bodies In The Eye: What To Do? Diagnosis And Treatment

Covid, A ‘Mask’ For The Eyes Thanks To Ozone Gel: An Ophthalmic Gel Under Study

Dry Eyes In Winter: What Causes Dry Eye In This Season?

What Is Aberrometry? Discovering The Aberrations Of The Eye

Dry Eye Syndrome: Symptoms, Causes And Remedies