Arteritic anterior ischemic optic neuropathy
Encyclopedia
Arteritic anterior ischemic optic neuropathy (AAION or arteritic AION) is the cause of vision loss
that occurs in temporal arteritis
(aka giant cell arteritis). Temporal arteritis is an inflammatory disease of medium-sized blood vessels that happens especially with advancing age. AAION occurs in about 15-20 percent of patients with temporal arteritis. Damage to the blood vessels supplying the optic nerve
s leads to insufficient blood supply (ischemia
) to the nerve and subsequent optic nerve fiber death. Most cases of AAION result in nearly complete vision loss first to one eye. If the temporal arteritis is left untreated, the fellow eye will likely suffer vision loss as well within 1–2 weeks. Arteritic AION falls under the general category of anterior ischemic optic neuropathy
, which also includes non-arteritic AION.
An exhaustive review article published in March 2009 described the latest information on arteritic and non-arteritic ischemic optic neuropathy, both anterior (A-AION and NA-AION) and posterior (A-PION, NA-PION, and surgical).
has a 15 percent incidence of giant cell arteritis.
Prompt diagnosis is critical, since the sudden blindness in the one eye is often followed, within days, by similar sudden blindness in the second eye. Treatment may prevent further damage (see below). Any patient diagnosed with non-arteritic AION over the age of 50 must be asked about the constitutional symptoms mentioned above. Furthermore, AION
patients over the age of 75 should often be blood tested regardless.
s to prevent further damage. While this treatment is in itself problematic, non-treatment leads to bilateral blindness and stroke
s.
There is much research currently underway looking at ways to protect the nerve (neuroprotection) or even regenerate new fibers within the optic nerve.
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:...
that occurs in temporal arteritis
Temporal arteritis
Giant-cell arteritis or Horton disease is an inflammatory disease of blood vessels most commonly involving large and medium arteries of the head...
(aka giant cell arteritis). Temporal arteritis is an inflammatory disease of medium-sized blood vessels that happens especially with advancing age. AAION occurs in about 15-20 percent of patients with temporal arteritis. Damage to the blood vessels supplying the optic nerve
Optic nerve
The optic nerve, also called cranial nerve 2, transmits visual information from the retina to the brain. Derived from the embryonic retinal ganglion cell, a diverticulum located in the diencephalon, the optic nerve doesn't regenerate after transection.-Anatomy:The optic nerve is the second of...
s leads to insufficient blood supply (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 nerve and subsequent optic nerve fiber death. Most cases of AAION result in nearly complete vision loss first to one eye. If the temporal arteritis is left untreated, the fellow eye will likely suffer vision loss as well within 1–2 weeks. Arteritic AION falls under the general category of anterior ischemic optic neuropathy
Anterior ischemic optic neuropathy
Anterior ischemic optic neuropathy is a medical condition involving loss of vision due to damage to the optic nerve from insufficient blood supply. AION is generally divided into two types: arteritic AION and non-arteritic AION...
, which also includes non-arteritic AION.
An exhaustive review article published in March 2009 described the latest information on arteritic and non-arteritic ischemic optic neuropathy, both anterior (A-AION and NA-AION) and posterior (A-PION, NA-PION, and surgical).
Symptoms and diagnosis
There are several constitutional symptoms of temporal arteritis that may aid in diagnosis of AAION such as jaw claudication (spasms of the jaw muscle), scalp tenderness, unintentional weight loss, fatigue, myalgias and loss of appetite. However, many cases are asymptomatic. There are also elevations in three blood tests that help identify AAION: erythrocyte sedimentation rate (ESR), C reactive protein (CRP) and platelet count (thrombocytosis). A related rheumatic disease called polymyalgia rheumaticaPolymyalgia rheumatica
Polymyalgia rheumatica , abbreviated as PMR, is a syndrome with pain or stiffness, usually in the neck, shoulders, and hips. The pain can be very sudden, or can occur gradually over a period of time...
has a 15 percent incidence of giant cell arteritis.
Prompt diagnosis is critical, since the sudden blindness in the one eye is often followed, within days, by similar sudden blindness in the second eye. Treatment may prevent further damage (see below). Any patient diagnosed with non-arteritic AION over the age of 50 must be asked about the constitutional symptoms mentioned above. Furthermore, AION
Aion
Aion may refer to:In music:*Aion , a Japanese metal band**Aion , their 1992 album*Aion , a Polish gothic metal band*Aion , a 2003 album...
patients over the age of 75 should often be blood tested regardless.
Treatment
AAION requires urgent and critical intervention with a very long course of corticosteroidCorticosteroid
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex. Corticosteroids are involved in a wide range of physiologic systems such as stress response, immune response and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte...
s to prevent further damage. While this treatment is in itself problematic, non-treatment leads to bilateral blindness and stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...
s.
There is much research currently underway looking at ways to protect the nerve (neuroprotection) or even regenerate new fibers within the optic nerve.