Associated symptoms

In the case of blindness, two different causes must be distinguished in order to describe the different symptoms. On the one hand, blindness can be congenital. These patients are born with it, grow up with the blindness and learn to cope with it.

They also do not know what it is like not to be blind. It is different with acquired blindness caused by diseases like glaucoma or age-related macular degeneration, where blindness is creeping and patients often have little time to adjust to it. Newborns are not always directly to see if they are blind.

With them it often shows itself through other symptoms. They are usually less attentive to their surroundings and recognize poorly presented faces. In addition, they often find it difficult to fixate on objects etc.

In addition, the lenses may become cloudy or strabismus may occur. Frequent rubbing of the eyes can also be a first sign. In case of complete blindness it is impossible for the eye to perceive light.

With acquired blindness, the symptoms usually come gradually or an accident causes direct blindness. Vascular occlusion can also lead to acute blindness. With creeping visual impairment, patients can no longer perceive their surroundings clearly.

Frequent bumping or falling is typical for the patients. The social aspect is also important. Due to increasing blindness, it could become more and more difficult for patients to leave the door. Social withdrawal is the consequence. Depression is also a common consequence of sudden blindness.

Blindness caused by methanol

Methanol is an alcohol whose intake is toxic to the body because it is converted to two harmful products in the liver. These are formaldehyde and formic acid. Both substances can only be broken down very slowly and accumulate in the body.

Formic acid leads to life-threatening hyperacidity of the body, which makes oxygen transport difficult and formaldehyde is toxic to some organs, especially the liver, kidneys and heart. The unintentional intake of methanol usually occurs when the alcohol ethanol used in high-quality alcoholic beverages is diluted with methanol, or when a liquor is improperly brewed by a private individual. Depending on the dose, methanol poisoning has different harmful effects.

In the eye, methanol poisoning initially causes a deterioration of visual acuity a few days later. This results in massive damage to the central nervous system and especially the optic nerve, which can lead to blindness. This can only be prevented by early therapy.

In most cases the therapy is carried out by administration of ethanol or fomepizole. These two substances bind to the enzyme, which normally converts methanol into its toxic products in the liver, thus preventing the processing of methanol. The supply of ethanol must be maintained until the entire amount of methanol absorbed has been excreted via the kidneys. In addition, a drug with a basic effect is given to compensate for the acidity caused by formic acid.