Amaurosis
Encyclopedia
Amaurosis is vision loss
or weakness that occurs without an apparent lesion affecting the eye
. It may result from either a medical condition or from excess acceleration, as in flight. The term is the same as the Latin gutta serena.
is an inherited disease resulting in optic atrophy and secondary severe vision loss or blindness
. It was first described by Theodore Leber in the 19th century.
Amaurosis fugax
(Latin: fugax meaning fugitive) is a temporary loss of vision in one eye caused by decreased blood flow
(ischemia
) to the retina
. Another cause is the presence of emboli located in the ipsilateral (same side) internal carotid artery. It is a type of transient ischaemic attack (TIA). Those experiencing amaurosis usually experience complete symptom abeyance within a few minutes. In a small minority of those who experience Amaurosis, stroke or vision loss has resulted. Diabetes, hypertension and smoking are factors known to increase the risks of suffering this condition. It also can be the result of surgical repair to the mitral valve, when very small emboli may break away from the site of the repair., while the patient's tissue grows to cover the plastic Annuloplasty band.
Quinidine
toxicity can lead to cinchonism
and also to quinine amaurosis.
This condition can also occur in ruminants suffering from a vitamin B1 (thiamine
) deficiency due to Thiamine-Related Cerebrocortical Necrosis
(CCN).
immediately as any form of vision loss, even if temporary, is a symptom
that may indicate the presence of a serious ocular or systemic problem.
Vision loss
Vision loss or visual loss is the absence of vision where it existed before, which can happen either acutely or chronically .-Ranges of vision loss:...
or weakness that occurs without an apparent lesion affecting the eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
. It may result from either a medical condition or from excess acceleration, as in flight. The term is the same as the Latin gutta serena.
Types
Leber's congenital amaurosisLeber's congenital amaurosis
Leber's congenital amaurosis is a rare inherited eye disease that appears at birth or in the first few months of life, and affects around 1 in 80,000 of the population.It was first described by Theodor Leber in the 19th century...
is an inherited disease resulting in optic atrophy and secondary severe vision loss or blindness
Blindness
Blindness is the condition of lacking visual perception due to physiological or neurological factors.Various scales have been developed to describe the extent of vision loss and define blindness...
. It was first described by Theodore Leber in the 19th century.
Amaurosis fugax
Amaurosis fugax
Amaurosis fugax is a transient monocular visual loss.-Pathophysiology and etiology:...
(Latin: fugax meaning fugitive) is a temporary loss of vision in one eye caused by decreased blood flow
Blood flow
Blood flow is the continuous running of blood in the cardiovascular system.The human body is made up of several processes all carrying out various functions. We have the gastrointestinal system which aids the digestion and the absorption of food...
(ischemia
Ischemia
In medicine, ischemia is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. It may also be spelled ischaemia or ischæmia...
) to the retina
Retina
The vertebrate retina is a light-sensitive tissue lining the inner surface of the eye. The optics of the eye create an image of the visual world on the retina, which serves much the same function as the film in a camera. Light striking the retina initiates a cascade of chemical and electrical...
. Another cause is the presence of emboli located in the ipsilateral (same side) internal carotid artery. It is a type of transient ischaemic attack (TIA). Those experiencing amaurosis usually experience complete symptom abeyance within a few minutes. In a small minority of those who experience Amaurosis, stroke or vision loss has resulted. Diabetes, hypertension and smoking are factors known to increase the risks of suffering this condition. It also can be the result of surgical repair to the mitral valve, when very small emboli may break away from the site of the repair., while the patient's tissue grows to cover the plastic Annuloplasty band.
Quinidine
Quinidine
Quinidine is a pharmaceutical agent that acts as a class I antiarrhythmic agent in the heart. It is a stereoisomer of quinine, originally derived from the bark of the cinchona tree.-Mechanism:...
toxicity can lead to cinchonism
Cinchonism
Cinchonism or quinism is a pathological condition in humans caused by an overdose of quinine or its natural source, cinchona bark. Quinine is medically used to treat malaria. In much smaller amounts, quinine is an ingredient of tonic drinks, acting as a bittering agent...
and also to quinine amaurosis.
This condition can also occur in ruminants suffering from a vitamin B1 (thiamine
Thiamine
Thiamine or thiamin or vitamin B1 , named as the "thio-vitamine" is a water-soluble vitamin of the B complex. First named aneurin for the detrimental neurological effects if not present in the diet, it was eventually assigned the generic descriptor name vitamin B1. Its phosphate derivatives are...
) deficiency due to Thiamine-Related Cerebrocortical Necrosis
Necrosis
Necrosis is the premature death of cells in living tissue. Necrosis is caused by factors external to the cell or tissue, such as infection, toxins, or trauma. This is in contrast to apoptosis, which is a naturally occurring cause of cellular death...
(CCN).
Management
Those experiencing amaurosis are usually advised to consult a physicianPhysician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...
immediately as any form of vision loss, even if temporary, is a symptom
Symptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
that may indicate the presence of a serious ocular or systemic problem.