Synonyms in a broader sense
Visual path lesion, optic nerve, chiasmal lesion, optic nerve
Introduction
The visual pathway begins at the retina of the eye and carries the visual sensations to the visual cortex of the cerebrum. Various failures occur along the visual path. Depending on the location of the damage to the visual pathway, different symptoms occur.
The various failures
- Chiasma Syndrome
- Damage to the optic tract (tractus opticus)
- Field of vision loss due to damage to the visual path
Chiasma Syndrome
In the course of the visual path, a partial crossing of the two optic nerves occurs in the area of the pituitary gland (pituitary gland). Disturbances in this area are called chiasma syndrome and manifest themselves through typical symptoms and complaints.
Damage to the optic tract (tractus opticus)
All lesions that lie behind the optic chiasma (Chiasma opticum) result in homonymous visual field defects. Homonymous visual field failures are characterized by the fact that either the right or left half of the visual field fails. This is due to the fact that the fibers running in the optic tract already contain crossed fibers of the opposite side.
This often leads to the loss of nerve fibers of the optic nerve. This often affects the visual radiation, but mostly the visual cortex. CausesThe most frequent cause is a stroke (apoplexy).
A stroke is an infarction of the visual cortex. This area responsible for conscious vision is no longer (sufficiently) supplied with blood. An infarction is caused by a vascular occlusion and the resulting lack of oxygen supply to the brain in the area of supply.
In the case of a visual disturbance, the cerebri media or posterior artery (middle and rear cerebral arteries) is most likely to be affected. These are arteries that supply the posterior part of the cerebrum, where the visual cortex is located. SymptomsSimilar to damage to the optic tract, homonymous (on the same side) visual field defects may occur.
The distinguishing feature is that there is no atrophy of the optic nerve. Pain does not occur either. TherapyIf necessary, the vascular occlusion is attempted to be repaired by medication. This is only successful if no more than 3 hours have passed since the event. Without treatment and even with treatment (lysis = dissolution of the blood clot), damage to the brain area remains.
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