Scotoma results in the presence of one or more spots in the visual field. There are several forms, the most described of which are the central scotoma with the presence of a black spot and the sparkling scotoma with several luminous spots in the visual field.
What is scotoma?
Definition of scotoma
The scotoma is a gap in the visual field. This is characterized by the following:
- the presence of one or more spots;
- regular or irregular;
- black or bright;
- in the center of the visual field, and sometimes at the periphery;
- in one eye, but sometimes in both eyes.
Types of scotoma
Many types of scotomas have been described. The most documented are:
- the central scotoma which results in the appearance of a black spot in the center of the visual field;
- The sparkling scotoma results in the appearance of sparkling spots that can be reminiscent of those caused by a flash of light.
Causes of scotoma
This visual field deficiency can have very different causes:
- macular degeneration, a deterioration of the macula (specific area of the retina) that is most often age-related (age-related macular degeneration, also simplified to AMD);
- damage to the optic nerve that may be due to different conditions such as a viral infection, inflammatory disease multiple sclerosis ;
- pressure on the optic chiasma (crossing point of the optic nerves) that can occur in the event of a stroke, hemorrhage, or a brain tumor
- vitreous detachment (gelatinous mass filling the eye) which is manifested by floaters (condensations) and which may in particular be due to aging, trauma, or surgery;
- an ophthalmic migraine, or migraine with visual aura, which is characterized by a glittering scotoma before the migraine attack.
Diagnosis of scotoma
An ophthalmologist performs confirmation of a scotoma. The eye cares professional checks visual acuity and analyzes the internal and external appearance of the eye. He rules out other possible explanations to confirm the diagnosis of the scotoma.
As part of his analysis, the ophthalmologist may use drops that dilate the pupils. These make it possible to observe the retina and the optic nerve but have the disadvantage of blurring vision for several hours. It is strongly recommended to be accompanied during this type of consultation.
The diagnosis may also be based on the results of angiography, a method that visualizes blood vessels.
Symptoms of scotoma
Spot(s) in the visual field
Scotoma results in the presence of one or more spots in the visual field. It can be a single spot or several small spots. In particular, the central scotoma with a black spot in the center of the visual field, and the sparkling scotoma with several bright spots in the visual field are distinguished.
Possible decrease in visual acuity
In some cases, scotoma can affect visual acuity. A person with a central scotoma may have difficulty performing precision activities such as reading or sewing.
The scintillating scotoma is a typical symptom of ophthalmic migraine. It often precedes a migraine attack.
In the absence of discomfort or complications, the scotoma may not be treated.
When treatment is possible and/or necessary, management may be based on:
- analgesic treatment;
- the use of antiplatelet drugs;
- laser surgery.
Some cases of scotoma can be prevented by adopting a healthy lifestyle and a few preventive measures. In particular, it may be advisable to:
- maintain a healthy, balanced diet that is a source of antioxidants (mainly fruits and vegetables) to strengthen eye protection;
- wear sunglasses with a suitable and effective protective shield;
- avoid smoking;
- Perform regular eye check-ups.
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