The optic nerve is an extension of the brain and its role is to transfer the visual stimuli received by the retina to the occipital lobe of the brain for processing and recognition.
The optic nerve can be inflamed, ischemic, chronic pressure, but can also develop a tumor, as well as atrophy.
Optic neuritis is an inflammation of the optic nerve and may be associated with diseases such as multiple sclerosis, autoimmune diseases such as Crohn’s disease and lupus erythematosus, but also with infectious diseases such as toxoplasmosis and tuberculosis. Symptoms: Decrease in central vision and disturbance in the perception of colors and brightness.
Anterior ischemic optic neuropathy or ischemic optic disease can be of two types: non-arteritic and arteritic.
The most common ischemic optic disease in people >50 years old. It is usually due to low perfusion, atherosclerosis, circulatory diseases and more rarely to embolism. Risk factors are arterial hypertension, cardiovascular diseases, diabetes mellitus and hypercholesterolemia.
Anterior ischemic optic disease manifests painlessly and suddenly with unilateral loss of vision which can be mild (30% of cases), or severe as it happens in most cases. In addition to the decrease in visual acuity, there is usually loss of visual field, color blindness and over time atrophy of the optic papilla of the optic nerve is possible.
In non-arteritic anterior ischemic optic neuropathy there is a risk of contracting the other eye, while adequate treatment has not yet been found.
Arteritic-type ischemic optic neuropathy or otherwise giant cell arteritis manifests itself in older people (>65 years). Its clinical picture resembles non-arteritic-type ischemic optic disease, but it is rarer and more serious. The decrease in visual acuity is so important that the patient can reach a level of finger-counting vision and noticeably limit his field of vision. Unfortunately, the chances of contracting the other eye are high and the prognosis is poor even with timely initiation of cortisone treatment.
The tumor in the optic nerve when it occurs during childhood is called glioma and when it occurs in middle-aged people (at a rate of 80% in women) it is called meningioma. Gliomas usually have a worse prognosis than meningiomas but in both cases there is partial to total vision loss. It requires surgery, so the optic nerve is necessarily resected and vision is further limited.
Atrophy of the optic nerve is divided into primary when it is of gene (hereditary) etiology and secondary when it is the result of other pathological conditions or trauma. In the first category belongs Lebe’r hereditary optic neuropathy. Secondary can be caused by inflammation, tumor or trauma. Symptoms: In both cases, progressive loss of vision occurs and there is no cure.
In all diseases of the optic nerve, when there is vision of 1/20 or more, the patient can be helped by using specially made low-vision glasses and use the remaining visual acuity, as well as increase his visual performance gradually.