Amaurosis (Greek meaning ''darkening'', ''dark'', or ''obscure'') is

vision loss Visual impairment, also known as vision impairment, is a medical definition primarily measured based on an individual's better eye visual acuity; in the absence of treatment such as correctable eyewear, assistive devices, and medical treatment� ...

or weakness that occurs without an apparent lesion affecting the

eye Eyes are organs of the visual system. They provide living organisms with vision, the ability to receive and process visual detail, as well as enabling several photo response functions that are independent of vision. Eyes detect light and conv ...

. It may result from either a medical condition or excess acceleration, as in flight. The term is the same as the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''gutta serena'', which means, in Latin, ''drop clear'' (or ''drop bright''). ''Gutta serena'' is a condition of partial or complete blindness with a transparent, clear pupil. This term contrasts with ''suffusio nigra'' which means, in Latin, ''suffusion dark'', indicating partial or complete blindness with a dark pupil, e.g., a cataract. Milton, already totally blind for twelve years (some scholars think from retinal detachment; others have diagnosed glaucoma) by the time he published

Paradise Lost ''Paradise Lost'' is an epic poem in blank verse by the 17th-century English poet John Milton (1608–1674). The first version, published in 1667, consists of ten books with over ten thousand lines of verse (poetry), verse. A second edition fo ...

, refers to these terms in Book 3, lines 25–26.

Types

Leber's congenital amaurosis Leber congenital amaurosis (LCA) is a rare inherited eye disease that appears at birth or in the first few months of life. It affects about 1 in 40,000 newborns. LCA was first described by Theodor Leber in the 19th century. It should not be co ...

is an inherited disease resulting in optic atrophy and secondary severe vision loss or

blindness Visual impairment, also known as vision impairment, is a medical definition primarily measured based on an individual's better eye visual acuity; in the absence of treatment such as correctable eyewear, assistive devices, and medical treatment� ...

. It was first described by

Theodore Leber Theodor Karl Gustav von Leber (29 February 1840 – 17 April 1917) was a German ophthalmologist from Karlsruhe. Leber was a student of Hermann von Helmholtz (1821-1894) in Heidelberg, where he received his doctorate in 1862. He remained in Heide ...

in the 19th century. Amaurosis fugax (Latin: ''fugax'' meaning ''fleeting'') is a temporary loss of vision in one eye caused by decreased blood flow (

ischemia Ischemia or ischaemia is a restriction in blood supply to any tissue, muscle group, or organ of the body, causing a shortage of oxygen that is needed for cellular metabolism (to keep tissue alive). Ischemia is generally caused by problems wi ...

) to the

retina The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then ...

. "Hersh: What causes amaurosis fugax, a temporary loss of vision?"
metrowestdailynews.com, Dec 4, 2012 It may also be caused by embolization from atherosclerotic plaques in the ipsilateral (same side) internal carotid artery. It is a type of

transient ischaemic attack A transient ischemic attack (TIA), commonly known as a mini-stroke, is a minor stroke whose noticeable symptoms usually end in less than an hour. TIA causes the same symptoms associated with strokes, such as weakness or numbness on one side of ...

(TIA). Those experiencing amaurosis usually experience complete symptom resolution within a few minutes. In a small minority of those who experience amaurosis, stroke or permanent vision loss results. 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 Cinchonism is a pathological condition caused by an overdose of quinine or its natural source, cinchona bark. Quinine and its derivatives are used medically to treat malaria and lupus erythematosus. In much smaller amounts, quinine is an ingredie ...

and also to quinine amaurosis.

Management

Those experiencing amaurosis are usually advised to consult a

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

immediately as any form of vision loss, even if temporary, is a

symptom Signs and symptoms are the observed or detectable signs, and experienced symptoms of an illness, injury, or condition. A sign for example may be a higher or lower temperature than normal, raised or lowered blood pressure or an abnormality showin ...

that may indicate the presence of a serious ocular or systemic problem.

In animals

This condition can also occur in ruminants suffering from a vitamin B₁ (

thiamine Thiamine, also known as thiamin and vitamin B1, is a vitamin, an essential micronutrient, that cannot be made in the body. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosphorylated forms of thi ...

) deficiency due to thiamine-related cerebrocortical necrosis (CCN).

References

Eye diseases Neurological disorders {{Symptom-stub