The macula in ophthalmology: diseases and treatment spectrum for macular degeneration

The macula, often referred to as the “yellow spot“, is a tiny area in the middle of the retina, but is of enormous importance for our vision. It is the place of sharpest vision – this is where we read, recognize faces and grasp details. However, it is precisely this central point of the eye that is susceptible to changes, especially in old age. Macular degeneration or macular edema can significantly impair vision and, in the worst case, lead to blindness in the central field of vision.

In this blog, you will find out what makes the macula so special, which diseases can affect it and which modern treatment options are available. We also show you how to recognize changes at an early stage and what aids can be used to maintain quality of life even with macular disease.

What is the macula – and why is it so important for vision?

The macula, also known as the “yellow spot”, is a small but central part of the retina – and plays a crucial role in our sharp vision. It is located exactly in the middle of the retina, opposite the pupil, at the back of the eye. Its main task is to enable us to focus on details, i.e. to read, recognize faces or see sharply at a point in the center of the field of vision.

The macula contains the highest density of light-sensitive photoreceptors (cones), which are responsible for color vision and high resolution. Without a functioning macula, central visual acuity is severely limited – even if peripheral vision is usually retained.

Structure and position of the macula in the eye

The macula is located in the central part of the retina and measures just a few millimetres in diameter – but is functionally the most important point for our vision. In its center is the fovea centralis, the point of absolute sharpest vision. This is where image signals are transmitted directly to the visual center in the brain.

The macula is particularly susceptible to age-related changes, as degradation products – known as drusen– can accumulate in this area due to the constant metabolic process. These can damage the sensitive tissue and lead to macular degeneration.

Diseases of the macula: when the center of the retina is affected

Diseases of the macula specifically affect the point in the middle of the retina that is responsible for sharp vision. Probably the best-known disease in this area is age-related macular degeneration (AMD) – it is considered the most common cause of blindness in old age in Western countries. However, macular edema, gliosis or macular holes can also impair the function of the center of the retina.

What is macular degeneration – and who does it affect?

Age-related macular degeneration (AMD) is a chronically progressive disease of the retina that usually occurs from the age of 50. With increasing age, metabolic deposits (drusen) accumulate in the pigment layer of the retina (RPE). These can disrupt the supply to the light-sensitive sensory cells (photoreceptors) and cause long-term damage.

Particularly affected are:

• People with a family history of stress
• People with strong sunlight without protection
• Smokers and people with high blood pressure or diabetes

The disease usually begins inconspicuously – regular check-ups with an ophthalmologist are therefore essential.

Dry and wet macular degeneration in comparison

There are two main forms of AMD:

• Dry macular degeneration: This occurs much more frequently and usually progresses slowly. Drusen are deposited under the retina, which gradually damage the surrounding tissue. There is no treatment for regression, but the progression can be positively influenced with nutritional supplements and lifestyle factors.
• Wet macular degeneration: This form often develops from dry macular degeneration and is much more aggressive. Leaking blood vessels grow under the macula and cause swelling, bleeding and a rapid deterioration in vision. The standard treatment consists of intravitreal injections with drugs that inhibit vascular growth.

Early warning signs and symptoms of macular disease

The onset of macular degeneration or other diseases of the center of the retina often become noticeable gradually. The first warning signs include

• Distorted vision (straight lines appear wavy or curved)
• Blurred letters when reading
• Weakening contrasts and colors
• A dark or gray spot in the center of the image
• Difficulty recognizing faces

A simple tool for self-checking is the Amsler grid: a test pattern with a grid in which distortions or missing lines can indicate a macular change.

Other diseases of the macula at a glance

In addition to age-related macular degeneration (AMD), there are a number of other macular diseases that can affect the function of the center of the retina – often with similar symptoms such as blurred vision, distorted lines or reading difficulties. An overview of three important diseases is presented here:

Macular edema – fluid retention in the center of the retina

Macular oedema occurs when fluid accumulates in the macula due to inflammatory processes or vascular leakage. The result is a swelling of the center of the retina, which significantly impairs vision. Common triggers are

• Diabetes mellitus (diabetic macular edema)
• Vascular occlusions in the retina
• Inflammation (uveitis)
• Operations on the eye, for example after cataract surgery

Symptoms:

• Distorted or blurred vision
• Problems with reading
• Reduced visual acuity

Macular hole – hole in the macula

A macular hole is a small hole in the fovea centralis, the center of the macula. It is usually caused by tensile forces between the vitreous body and the retina, especially in people over 60. It can also occur after operations or injuries.

Symptoms:

• Sudden loss of central visual acuity
• A dark spot or blind spot in the center
• Distorted vision

Epiretinal gliosis – fine membrane on the retina

In epiretinal gliosis (also known as macular pucker), a cellular membrane forms on the surface of the macula, which can contract and deform the retina. The causes are usually age-related, but can also occur after inflammation, injury or surgery.

Symptoms:

• Distorted vision (“straight lines appear wavy”)
• Reduced visual acuity
• “Crease effect” in central vision

How can macular diseases be recognized?

Diseases of the macula often develop gradually – and go unnoticed for a long time. This is precisely why regular ophthalmological examinations are important, especially from the age of 50 or if there is a known family history. If detected early, many macular diseases can be slowed down or treated well – before permanent damage to the center of the retina occurs.

Typical examination methods: OCT, Amsler grating & Co.

Various methods are available in modern ophthalmology for early detection and monitoring the progression of the disease:

• OCT (optical coherence tomography): Currently the most important imaging procedure. It enables non-contact, high-resolution cross-sectional images of the retina – ideal for detecting drusen, fluid deposits or membranes.
• Amsler grid test: A simple grid with a fixation point in the center. Anyone who sees distorted lines, waves or blank spots when looking at the screen should see an ophthalmologist as soon as possible.
• Funduscopy (examination of the back of the eye): For direct assessment of the macula – usually after pupil dilation with eye drops.
• Fluorescein angiography: Particularly used in wet macular degeneration to visualize leaking vessels.

When is an early diagnosis crucial?

Especially in the case of macular degeneration, macular oedema or macular holes, the time of diagnosis is crucial. If the disease is detected at an early stage, the chances of successful treatment are much higher. If left untreated, irreversible damage to the light-sensitive sensory cells can occur – with permanent impairment of central vision.

Treatment options for macular diseases

The treatment of macular diseases depends heavily on the type and stage of the disease and the individual visual impairment.

Drug therapy – injections into the eye

The most important treatment for wet macular degeneration and macular oedema is intravitreal injections. This involves injecting medication – usually so-called VEGF inhibitors – directly into the vitreous cavity of the eye.

Effect of the medication:

• Inhibition of unwanted vascular growth
• Reduction of fluid accumulation in the retina
• Stabilization or even improvement of visual performance

The injections are carried out at regular intervals and under sterile conditions in the eye clinic. Today, they are the gold standard for many inflammatory or vascular macular diseases.

Laser treatment and surgical procedures

Depending on the findings, laser procedures or surgical interventions may also be used:

• Laser coagulation: selective obliteration of leaky vessels (less common today, but still used for vascular changes outside the macula, for example)
• Vitrectomy: surgical removal of the vitreous body, e.g. in the case of a macular hole or epiretinal gliosis
• Membrane peeling: in the case of epiretinal gliosis, the fine membrane over the macula is carefully removed to smooth the retina again

These procedures are performed exclusively in specialized eye clinics and require a precise ophthalmological indication.

Living with macular degeneration – what helps in everyday life?

Although there is no cure for advanced macular degeneration, especially the dry form, there are numerous aids and strategies to make everyday life easier:

• Magnifying visual aids such as magnifying glasses, screen readers or electronic reading devices
• Enlarged font sizes on the PC, smartphone or e-reader
• Vision training and low-vision advice from specialist opticians or clinics
• Light optimization in the living area, e.g. with glare-free lights and daylight lamps
• Psychological support if insecurities or fears are a burden on everyday life

Important: Even if your vision is already deteriorating, it is worth having regular check-ups with an ophthalmologist – because the progression can often be stopped or slowed down.