Vitreous Opacity : Symptoms Causes & Treatment

Many people suffer from vitreous opacity. Those affected report that they see black dots that seem to dance in front of their eyes. The phenomenon is also known as “mouches volantes” (French for “flying flies”). A vitreous opacity is harmless, but interferes with vision. After a while, the symptoms often go away on their own. Read more about the causes and treatment of vitreous opacities here.

ICD codes for vitreous opacity disease: H43

Vitreous opacity: description

Many people suffer from vitreous opacities in the eye and the associated “mouches volantes”. This is due to a natural aging process. Around two thirds of 65 to 85 year olds complain about such complaints. But younger people can also be affected, especially if they are severely short-sighted.

What is the vitreous?

The gelatinous vitreous humor fills most of the inside of the eyeball. In front of him is the lens, which optically refracts light rays entering the eye. These then pass through the vitreous body to the retina. It lies behind the vitreous body and, as the light-sensitive layer of nerve cells, is responsible for converting the optical images into electrical impulses. In this way, the information can be transmitted to the brain via the optic nerves.

Symptoms of vitreous opacity

A clouding of the vitreous is most often expressed by so-called “mouches volantes” – French for “flying flies”. The term “flying mosquitoes” or “dancing mosquitoes” is often used in German. Because those affected usually describe the dark or semi-transparent dots, stripes or streaks that they perceive as insects dancing in front of their eyes. This is not an illusion of the senses. The forms actually exist in the vitreous body.

“Flying mosquitoes” do not restrict vision and are usually harmless. Nevertheless, many patients complain that their subjective sense of vision deteriorates. As a result, the vitreous opacity is perceived as annoying. On the one hand, the cloudiness and shadows vary in strength and location. On the other hand, scattered light can dazzle the patient.

Floating floaters are especially noticeable when patients look at a bright wall or bright light, or are blinded by snow.

Vitreous opacity: causes and risk factors

The vitreous humor, which fills the inside of the eye, consists mainly of water and, to a lesser extent, collagen fibers and hyaluronic acid. In childhood, the fibers are arranged regularly so that they are not perceived – they hardly affect the light rays on their way to the retina.

With increasing age, however, the vitreous body shrinks and the fibers lose their structure. They are now increasingly disordered and resemble threads or even form flat structures. If the vitreous continues to shrink with age, at some point it also loses contact with the retina. Then it oscillates sluggishly with eye movements. This allows the threads and streaks to come into focus. They then cast shadows on the retina – the person affected can see black dots (mouches volantes).

Over the course of months, the fibers move further and further away from the retina. They are then perceived as blurry and weaker until at some point they are no longer perceptible at all.

Age is considered the most important risk factor for the development of vitreous opacity, since it is usually an age-related process. Short-sighted people often notice the “flying mosquitoes” a little earlier than normal or far-sighted people.

Vitreous opacity: investigations and diagnosis

If for the first time you see something that does not exist outside of your eye, consult your eye doctor. It can be a harmless vitreous opacification, but also another disease. In order to find out, your ophthalmologist will first ask you in detail about your medical history. Possible questions are:

  • For example, what do you see when you look at a white wall?
  • When did you first become aware that you were seeing “flying mosquitoes” (black dots)?
  • Did the symptoms appear suddenly or have they suddenly increased?
  • Is it isolated spots and streaks that you see, or rather soot rain and snow flurries?
  • Do you see flashes of light?
  • Are you nearsighted?
  • Have you had any injuries, inflammation or operations (cataract surgery, retinal laser treatment) on your eyes?
  • Have you had a retinal detachment in the other eye in the past?


To get a better look inside your eye, your doctor will first give you eye drops that dilate the pupil. Then follows a slit lamp examination : your doctor shines a bright lamp, the so-called slit lamp, into your eye from the side and examines the individual components through a magnifying glass. In the case of a vitreous opacity, he recognizes dark shadows. The slit lamp examination is painless and uncomplicated.

The eyesight can be limited for a few hours due to the pupil-dilating eye drops. You should therefore refrain from driving until the effect wears off.

Differential diagnoses

If a vitreous opacity cannot be clearly diagnosed by the slit lamp examination or if the medical history is not entirely conclusive, further examinations must clarify whether other causes could be responsible for the symptoms (differential diagnoses):

An ultrasound examination is primarily used to identify or rule out a retinal detachment as the cause of the symptoms. This is an ophthalmological emergency that must be treated quickly, otherwise there is a risk of blindness! The perception of flashes of light and “soot rain” is typical of a retinal detachment.

X- rays, computed tomography (CT) or magnetic resonance imaging (MRI) can be used to determine whether a foreign body in the affected eye is causing symptoms of vitreous opacity.

In addition, as differential diagnoses in vitreous opacities, for example, inflammation of the middle layer of the eye (uveitis) and vitreous hemorrhage come into question.

Treatment of vitreous opacities

As a rule, no therapy is necessary for a vitreous opacity. Although the “mouches volantes” are perceived as annoying by many of those affected, they are harmless and often disappear on their own. Until then, the symptoms can be alleviated with a few tips (see below).

A vitreous removal (vitrectomy) is sometimes offered as a radical solution to a vitreous opacity. The vitreous body is sucked out and the resulting cavity is filled with a special liquid, silicone oil or gas. However, the majority of ophthalmologists advise against this treatment for vitreous opacities, as the risks usually outweigh the benefits! Vitreous removal can cause blindness, for example if it causes a retinal tear or infection. The risk of developing retinal holes during vitreous removal is between 12 and 30 percent. In addition, lens opacification occurs in many patients after the operation.

Laser therapies are also not recommended for the treatment of floaters.

These tips can help relieve symptoms

Doctors advise patients with vitreous opacity to ignore the symptoms as much as possible. In addition, there are a number of things you can do yourself to alleviate the symptoms:

  • Wear sunglasses with a high sun protection (85 percent) on bright sunny days or in the snow.
  • Avoid white or very light walls in your own home. Textured wallpaper or muted wall colors distract the eye more.
  • Many decorative elements in the home, such as flowers, bookshelves or pictures, are useful.
  • If you spend a lot of time at the computer, turn down the brightness and choose the contrast that is comfortable for you.
  • Self-tinting lenses are particularly helpful in the case of severe short-sightedness. These darken within seconds when those affected are exposed to bright light.

Vitreous opacity: disease course and prognosis

A vitreous opacity usually does not require further treatment by a doctor – the floaters often disappear completely and all by themselves. However, this can take up to several years. Gradually, the “flying gnats” become fewer, as the fibers and the entire vitreous body move away from the retina and are therefore less visible.

Nevertheless, the following applies: When floaters occur for the first time, you should definitely see an ophthalmologist. He can determine whether it is actually a harmless vitreous opacification or whether there is a more serious cause behind the symptoms.

Even if “flying gnats” suddenly appear in swarms or you see dense soot rain, you should urgently see an ophthalmologist. Like flashes of light, these symptoms can indicate an impending retinal detachment and against a simple vitreous body opacity.

Dr. Ashwani Kumar is highly skilled and experienced in treating major and minor general medicine diseases.