Floating opacities before the eyes: causes, symptoms, treatment

Floating opacities - these are flies and thread-like formations that move in the field of view of a person, but have nothing to do with external objects. Floating cloudiness is quite common.

Causes and risk factors

Floating opacities are the result of stimulation of the retina (which is the light-sensitive structure at the back of the eye) with something that has nothing to do with ambient light. This stimulation causes the retina to send a signal to the brain. The brain can interpret the signal as a visible object floating in the field of view (floating front sight) or as a normal sudden flash of light that may look like lightning, spots, or stars (photopsy). Photopsia can occur when the eyes are rubbed.

The most common cause of floating cloudiness is

• a decrease in the volume of the gelatinous substance that fills the eyeball (vitreous).

At the age of 50 to 75 years, the volume of the vitreous body decreases, which periodically pulls the retina. This pulling force stimulates the retina, creating the illusion of light or an object, which the person sees as floating opacities. Such floaters (idiopathic floaters of the vitreous humor) are not harmful. Less commonly, there are cases when the vitreous body completely departs from the retina (detachment of the vitreous body).

Uncommon, but more serious causes may be:

• retinal detachment;
• perforation of the retina;
• detachment of the vitreous body;
• vitreous hemorrhage;
• inflammation of the vitreous body.

Sometimes migraine may cause symptoms of visual impairment. These visual impairment symptoms may appear as white, flickering lines with jagged edges that first appear in in the middle of the field of view, and then spread throughout the entire field of view (unlike floating opacities, these are not isolated objects). They usually disappear within about 20 minutes, first from the peripheral visual fields and then from the center of the visual field. They may not be accompanied by a headache. These symptoms are called ocular or visual migraines. Patients may experience similar symptoms or lose sight in any part of the eye for 10 to 60 minutes, often before the onset of a migraine headache (migraine aura). In such cases, the cause of the symptoms is a process in the brain, not in the retina.

In rare cases, floaters are caused by tumors (eg, lymphoma) of the eye and vitreitis (inflammation of the vitreous humor). Foreign bodies in the eye can cause floaters, but it usually causes other symptoms, such as loss of vision, eye pain, or redness, that are more bothersome than floating clouding.

Survey

Not all cases of floaters require immediate medical attention. The information below will help you decide when to see a doctor and what will happen during the examination.

Warning signs

When floaters are present, certain symptoms and signs may be cause for concern. They include:

• a sudden increase in floating opacities;
• repeated, often lightning-like flashes of light;
• complete or partial loss of vision (often there is a feeling that part of the field of vision is covered by a shadow or curtain);
• recent surgery or eye injury;
• pain in the eye.

When to see a doctor

Despite the fact that in most cases, floating opacities are not a reason for anxiety, people who have warning signs should contact ophthalmologist. They may have severe vitreous or retinal diseases, and a delay of several days, sometimes even hours, can lead to permanent loss of vision. Patients who begin to notice floating opacities without warning signs should see a doctor whenever possible, although a delay of a few days or more is most likely not will cause harm. Patients who have had floaters and no other symptoms for some time should have an eye exam, but time is not a critical factor.

What the doctor does

Doctors first ask the patient about their symptoms and medical history. They then do a physical examination. The data obtained from the history and physical examination often indicate the cause of the floaters and the tests that may be required.

Doctors ask for a description of floaters and then ask:

• When did the patient notice floating opacities?
• What are the distinguishing characteristics of floating opacities (for example, their shape, movement, or when they reappear)?
• Do floaters appear in one or both eyes?
• Does the patient see flashing lights, or does it seem that part of the field of vision is missing or covered by a curtain?
• Has the patient had an eye injury or eye surgery?
• Are there other symptoms (such as blurred vision, eye redness, eye pain, or headaches)?
• Does the person suffer myopia?
• Does the person have a medical condition that can affect vision, such as diabetes or diseases of the immune system (for example, AIDS)?

The eye exam is the most important part of the physical exam. Doctors check visual acuity, eye movement, and pupil response to light. They also check for redness in the eyes and the visual field for loss of vision areas.

Ophthalmoscopy is the most important part of the eye examination. Doctors first use drops to dilate the pupils. They then use an ophthalmoscope (a magnifying glass lamp that illuminates the back of the eye) to examine the internal structures of the eye, including as much of the retina as possible. If there is a suspicion that the floaters are due to a serious cause, an examination by an ophthalmologist is mandatory. An ophthalmologist is a doctor who specializes in the diagnosis and treatment (surgical or nonsurgical) of eye diseases.

The pressure in the eye (intraocular pressure) is measured after the anesthetic has been instilled into the eye.

Doctors place a drop of fluorescein dye into the eye and then use a slit lamp (a device that allows a doctor to examine the eye at high magnification) to examine the entire eye.

Analyzes

Doctors can often identify less severe floater problems on examination, but if there is a suspicion of a serious illness, they refer patients to an ophthalmologist for staging diagnosis. Ophthalmologists are doctors who specialize in the diagnosis and treatment (surgical or nonsurgical) of eye diseases. The ophthalmologist does a more detailed ophthalmoscopy and can prescribe tests and examinations. For example, with inflammation of the vitreous body of an infectious origin, studies are prescribed that are carried out to identify the microorganisms that are believed to have caused the infection.

Treatment

Floating opacities associated with processes in the vitreous are floating opacities arising from contractions of the gelatinous substance that fills the eyeball, which is called the vitreous humor, and they do not require treatment.

Sometimes, if there are so many floaters that they interfere with vision, doctors may use a cannula to remove the vitreous from the eye and replace it with salt water. This surgical procedure is called vitrectomy. However, many doctors believe that vitrectomy should not be done due to floating opacities, since the procedure can lead to retinal detachment or cataracts, and because floating opacities sometimes persist after procedures.

Other diseases causing the symptoms are treated. For example, surgery is performed to repair a detached retina. In the presence of infections that cause inflammation of the vitreous body, antimicrobial drugs are used.