Those spots, threads or cobwebs that seem to float in the visual field are usually harmless, but in certain cases they announce an ophthalmological emergency that can permanently compromise vision if not treated in time.
Almost everyone has seen them at some point: small dark dots, filaments or spiderweb-like shapes that move across the field of vision, especially when looking at a white wall or a clear sky. They are called myodesopsias, although they are popularly known as “floaters.”
In most cases they are part of the natural aging of the eye and do not represent any danger. The problem is that, in a smaller but significant percentage, they hide the beginning of a retinal tear or detachment, a medical emergency capable of leaving irreversible consequences if time is lost.
Eye aging
The interior of the eyeball is occupied by the vitreous humor, a transparent gel that, over the years, loses consistency. Some of its collagen fibers clump together and form small condensations that cast shadows on the retina, the light-sensitive tissue located at the back of the eye. These shadows are what the brain interprets as moving spots, threads or points that “escape” when you try to focus on them directly.
This phenomenon, known as posterior vitreous detachment, usually occurs most frequently between the ages of 50 and 75, although it can also appear earlier in people with high myopia, after cataract surgery or after eye trauma. It is a very common process after the age of 50 or 60 and, in the vast majority of cases, it is benign.
Why sometimes it becomes an emergency
The risk appears when, upon separating, the vitreous gel pulls on the retina at some point and eventually tears it. This mechanical pull stimulates the retina, which sends a signal interpreted by the brain as a flash of light, and if fluid leaks behind the tear, the retina can end up detaching. According to estimates cited by specialists, up to 5% of people who have myodesopsias could develop a retinal tear, and of those cases, around half progress to a complete retinal detachment.
A retinal detachment is, in the words of ophthalmologists, one of the most serious emergencies in the specialty: it interrupts the blood supply to the retinal tissue and, without prompt treatment, can cause permanent vision loss.
Signs that should not be ignored
Specialists agree on the same message: not all floaters are the same, and the most common mistake is to assume that they are always harmless and postpone the consultation. It is advisable to go immediately to the ophthalmologist or to an emergency service before:
These symptoms can occur without pain, leading many people to downplay them. However, ophthalmologists insist that the absence of discomfort does not rule out severity: the review must be immediate precisely because the retinal tear can be treated with laser preventively before it evolves into a complete detachment.
Those who are most at risk
Although anyone can experience this phenomenon with age, there are groups with a higher probability of complications: people with high myopia, those who have undergone cataract surgery, those who have a family history of retinal detachment, patients with peripheral retinal degenerations and people with advanced diabetic retinopathy or ocular vascular obstructions. For these groups, periodic ophthalmological check-ups are especially important, even in the absence of symptoms.
Diagnosis and treatment
If a tear or detachment is suspected, the ophthalmologist performs a fundus examination, sometimes accompanied by visual acuity tests and studies such as optical coherence tomography. If a tear is detected early, the laser is usually enough to seal it and prevent it from progressing.
When there is already a detachment, the usual treatment is surgical. Vitrectomy is one of the most used procedures. and its success depends largely on how quickly action is taken from the appearance of symptoms.
