Amaurosis is the temporary or permanent loss of vision, which can happen gradually, affecting only one or both eyes and can happen due to changes in the electrical activity of the retina or decreased blood flow to the eye, which may be a consequence of diseases such as atherosclerosis, ischemia or thrombosis, for example. In addition, amaurosis can also happen due to migraine attacks, stress or be a consequence of blows to the eye.
It is important that the cause of amaurosis is investigated by the ophthalmologist, as this may indicate the most appropriate treatment, which may involve the use of medication.
Amaurosis usually occurs when there is an alteration in the supply of oxygen-rich blood to the eye region, or when there is an alteration in the functioning of the retinal nerves, which causes a temporary or permanent loss of vision. According to the cause, amaurosis can be classified into some main types, such as:
- Quinine amaurosis, which can happen due to the increased concentration of quinidine in the blood;
- Leber’s Amaurosis, which is a type of rare hereditary degenerative disease in which there is an alteration in the electrical activity of the retina, which causes a gradual loss of vision;
- fleeting amaurosis, which happens mainly due to decreased blood flow to the eye, which can be a consequence of atherosclerosis, ischemia, heart failure, decompensated diabetes, thrombosis and hypertension crisis, for example.
In addition, other possible causes of amaurosis are:
- Migraine attacks;
- Panic attack;
- Vitreous hemorrhage;
- Anterior ischemic optic neuropathy;
- Vitamin B12 deficiency;
- Corneal trauma;
- Cocaine abuse;
- Toxoplasmosis or cytomegalovirus infections;
- High plasma viscosity.
Amaurosis can affect only one or both eyes and can be temporary or permanent and, therefore, it is important that the ophthalmologist is consulted so that tests can be done to help complete the diagnosis and initiate the most appropriate treatment.
How to confirm the diagnosis
The diagnosis of amaurosis must be made by the ophthalmologist through an eye examination and evaluation of other symptoms that the person may be presenting. Through the eye exam, the doctor can check for signs of eye damage that could be the cause of amaurosis.
However, as amaurosis can happen as a result of diseases, it may also be indicated to carry out blood tests so that it is possible to identify the cause. Thus, it may be recommended to perform a complete blood count, measurement of C-reactive protein, total cholesterol and fractions, triglycerides and glucose levels, in addition to an echocardiogram and assessment of the carotid vein circulation, which can be done by doppler or angioresonance, so that it can be confirmed what caused the amaurosis and thus start the appropriate treatment.
How is the treatment done
Treatment for amaurosis aims to treat the cause of the visual change, and it is important to follow the guidance of the ophthalmologist or general practitioner. Thus, depending on the cause, the use of antiplatelet agents, antihypertensives and corticosteroids may be indicated.
In more severe cases, when amaurosis occurs due to obstruction of the carotid artery due to stenosis, atherosclerosis or the presence of clots, for example, the physician may recommend surgery to treat the cause and thus reduce the risk of complications, especially stroke.