What happens in the eye
The choroid is located between the sclera and the retina and contains a dense network of vessels. Through them, pathogens or immune cells can enter the eye, causing inflammation. In the lesion, the tissue swells, infiltrates, and the nutrition of the photoreceptors is disrupted. A suspension of cells appears in the vitreous body, causing the effect of fog and floating spots. After the inflammation subsides, a scar with pigment remains at the site of the outbreak: in this area, the retina no longer perceives light, and a persistent blind spot remains in the field of vision.
- The central focus is in the area of the macula, most severely reduces vision
- Peripapillary - around the optic disc
- Peripheral - at the edge of the fundus, can occur unnoticed
- Focal, multifocal and diffuse options
- The outcome of inflammation is a pigmented retinal scar
Reasons
The most common infectious cause is toxoplasmosis, often congenital: the lesion exists from birth and is activated years later. Tuberculosis, syphilis, herpes group viruses, cytomegalovirus in people with weakened immune systems, and less often fungal infections play a role. The second large group is autoimmune and systemic diseases: sarcoidosis, Behcet's disease, ankylosing spondylitis. Eye injuries and complications of high myopia are considered separately. In approximately some patients the cause cannot be determined.
- Toxoplasmosis, including congenital
- Tuberculosis and syphilis
- Herpes viruses, cytomegalovirus
- Sarcoidosis, Behçet's disease, systemic vasculitis
- Eye injuries and surgeries
- High myopia, decreased immunity
Symptoms
Complaints depend on where the outbreak is located. Inflammation in the center causes a rapid drop in visual acuity, a dark spot right in front of the eye and distortion of lines: the door frame looks curved, the letters in the text jump. A peripheral lesion may not bother you at all and is discovered by chance during examination. Floaters are almost always present - a consequence of cells trapped in the vitreous body. Some report flashes of light, blurred vision at dusk, and changes in color perception. Redness and pain are more likely to be characteristic of inflammation of the anterior parts of the eye.
- Fog and decreased visual acuity
- Floaters and spots in front of the eye
- Dark spot in the field of view
- Distortion of straight lines
- Flashes of light
- Deterioration of vision at dusk
Diagnostics
It is mandatory to examine the fundus with dilation of the pupil - this is the only way to see lesions and scars. Optical coherence tomography shows retinal swelling and the condition of its layers in great detail and is used to monitor treatment. Computer perimetry records loss in the field of view. Ultrasound of the eye helps when the vitreous body is cloudy and the fundus cannot be examined. At the same time, they are looking for the cause: tests for toxoplasmosis, syphilis, tuberculosis, HIV, and for systemic complaints - a rheumatological examination and chest x-ray.
- Ophthalmoscopy with pupil dilation
- Optical coherence tomography of the retina
- Computer perimetry
- Ultrasound of the eye in B-mode
- Tests for toxoplasmosis, syphilis, tuberculosis, HIV
- Consultations with an infectious disease specialist and rheumatologist according to indications
Treatment and prevention
The tactics are determined by the cause, so self-medication is unacceptable: drugs that help with autoimmune inflammation can dramatically worsen the course of the infectious process. For toxoplasmosis, antiparasitic drugs are prescribed, for tuberculosis and syphilis - specific therapy, for a viral nature - antiviral drugs. Anti-inflammatory and hormonal drugs are used according to strict indications, in drops, as injections near the eye or systemically. Active inflammation in the central zone is treated urgently to preserve visual acuity. After recovery, periodic examinations are needed: chorioretinitis is prone to relapses.
- Treatment of an established cause as prescribed by a doctor
- Anti-inflammatory and hormonal therapy according to indications
- Injecting medication near the eye
- Monitoring using OCT and perimetry
- Laser treatment for retinal complications
- Regular fundus examinations after recovery
