|
Anterior Ischemic Optic Neuropathy
Anterior ischemic optic neuropathy (AION) is a medical condition involving loss of vision caused by damage to the anterior portion of the optic nerve as a result of insufficient blood supply (ischemia). This form of ischemic optic neuropathy is generally categorized as two types: arteritic AION (or AAION), in which the loss of vision is the result of an inflammatory disease of arteries in the head called temporal arteritis, and non-arteritic AION (abbreviated as NAION, NAAION, or sometimes simply as AION), which is due to non-inflammatory disease of small blood vessels. It is in contrast to posterior ischemic optic neuropathy, which affects the retrobulbar portion of the optic nerve. Symptoms NAION typically presents suddenly upon awakening. The affected person notes seeing poorly in one eye. Vision in that eye is obscured by a dark shadow, often involving just the upper or lower half of vision, usually the area closer to the nose. There is no pain. Within approximately s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Visual Loss
Visual or vision impairment (VI or VIP) is the partial or total inability of visual perception. In the absence of treatment such as corrective eyewear, assistive devices, and medical treatment, visual impairment may cause the individual difficulties with normal daily tasks, including reading and walking. The terms ''low vision'' and ''blindness'' are often used for levels of impairment which are difficult or impossible to correct and significantly impact daily life. In addition to the various permanent conditions, fleeting temporary vision impairment, amaurosis fugax, may occur, and may indicate serious medical problems. The most common causes of visual impairment globally are uncorrected refractive errors (43%), cataracts (33%), and glaucoma (2%). Refractive errors include near-sightedness, far-sightedness, presbyopia, and astigmatism (eye), astigmatism. Cataracts are the most common cause of blindness. Other disorders that may cause visual problems include age-related macular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Beta Blocker
Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms ( arrhythmia), and to protect the heart from a second heart attack after a first heart attack ( secondary prevention). They are also widely used to treat high blood pressure, although they are no longer the first choice for initial treatment of most people. Beta blockers are competitive antagonists that block the receptor sites for the endogenous catecholamines epinephrine (adrenaline) and norepinephrine (noradrenaline) on adrenergic beta receptors, of the sympathetic nervous system, which mediates the fight-or-flight response. Beta-adrenergic receptors are found on cells of the heart muscles, smooth muscles, airways, arteries, kidneys, and other tissues that are part of the sympathetic nervous system and lead to stress responses, especially when they are stimulated by epinephrine (adrenaline). Beta blockers interfere with the binding to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Sohan Hayreh
Sohan Singh Hayreh (November 6, 1927 – September 29, 2022) was an ophthalmologist, clinical scientist, and professor emeritus of ophthalmology at the University of Iowa. As one of the pioneers in the field of fluorescein angiography, he was generally acknowledged to be a leading authority in vascular diseases of the eye and the optic nerve. For over 60 years, Hayreh was actively involved in basic, experimental, and clinical research in ophthalmology, publishing over 400 original peer-reviewed articles in various international ophthalmic journals, six classical monographs and books in his field of research, and more than 50 chapters in ophthalmic books.Living legends in ophthalmology - Prof Sohan Singh Hayreh. Indian J Ophthalmol 2018;66:1673. He made many seminal observations dealing with the ocular circulation in health and disease, the optic disc and the optic nerve, retinal and choroidal vascular disorders, glaucomatous optic neuropathy, fundus changes in malignant arterial hype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Tumor Necrosis Factor
Tumor necrosis factor (TNF), formerly known as TNF-α, is a chemical messenger produced by the immune system that induces inflammation. TNF is produced primarily by activated macrophages, and induces inflammation by binding to its receptors on other cells. It is a member of the tumor necrosis factor superfamily, a family of transmembrane proteins that are cytokines, chemical messengers of the immune system. Excessive production of TNF plays a critical role in several inflammatory diseases, and TNF-blocking drugs are often employed to treat these diseases. TNF is produced primarily by macrophages but is also produced in several other cell types, such as T cells, B cells, dendritic cells, and mast cells. It is produced rapidly in response to pathogens, cytokines, and environmental stressors. TNF is initially produced as a type II transmembrane protein (tmTNF), which is then cleaved by TNF alpha converting enzyme (TACE) into a soluble form (sTNF) and secreted from the cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Pentoxifylline
Pentoxifylline, also known as oxpentifylline, is a xanthine derivative used as a drug to treat muscle pain in people with peripheral artery disease. It is generic and sold under many brand names worldwide like Trental.Drugs.codrugs.com international listings for Pentoxifylline Page accessed Feb 1, 206 Medical uses Its primary use in medicine is to reduce pain, cramping, numbness, or weakness in the arms or legs which occurs due to intermittent claudication, a form of muscle pain resulting from peripheral artery diseases. This is its only FDA, MHRA and TGA-labelled indication. However, pentoxifylline is also recommended for off-label use as an adjunct to compression bandaging for the treatment of chronic venous leg ulcers by the Scottish Intercollegiate Guidelines Network (SIGN) as this has been shown to improve healing rates. Pentoxifylline has been tested for use in sarcoidosis patients as an alternative or complement to prednisone and other steroids, as the drug can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Cochrane (organisation)
Cochrane is a British international charitable organisation formed to synthesize medical research findings to facilitate evidence-based choices about health interventions involving health professionals, patients and policy makers. It includes 53 review groups that are based at research institutions worldwide. Cochrane has over volunteer experts from around the world. The group conducts systematic reviews of healthcare interventions and diagnostic tests and publishes them in the Cochrane Library. While Cochrane reviews typically focus on randomized controlled trials, some reviews, particularly in areas such as public and occupational health, also incorporate other study designs. These may include non-randomised observational studies as well as controlled before–after (CBA) studies and interrupted time-series studies. According to the Library, articles are available via one-click access, though some may require registration or a subscription. History Cochrane, prev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Odds Ratio
An odds ratio (OR) is a statistic that quantifies the strength of the association between two events, A and B. The odds ratio is defined as the ratio of the odds of event A taking place in the presence of B, and the odds of A in the absence of B. Due to symmetry, odds ratio reciprocally calculates the ratio of the odds of B occurring in the presence of A, and the odds of B in the absence of A. Two events are independent if and only if the OR equals 1, i.e., the odds of one event are the same in either the presence or absence of the other event. If the OR is greater than 1, then A and B are associated (correlated) in the sense that, compared to the absence of B, the presence of B raises the odds of A, and symmetrically the presence of A raises the odds of B. Conversely, if the OR is less than 1, then A and B are negatively correlated, and the presence of one event reduces the odds of the other event occurring. Note that the odds ratio is symmetric in the two events, and no causa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Giant-cell Arteritis
Giant cell arteritis (GCA), also called temporal arteritis, is an inflammatory autoimmune disease of large blood vessels. Symptoms may include headache, pain over the temples, flu-like symptoms, double vision, and difficulty opening the mouth. Complications can include blockage of the artery to the eye with resulting blindness, as well as aortic dissection, and aortic aneurysm. GCA is frequently associated with polymyalgia rheumatica. The cause is unknown. The underlying mechanism involves inflammation of the small blood vessels that supply the walls of larger arteries. This mainly affects arteries around the head and neck, though some in the chest may also be affected. Diagnosis is suspected based on symptoms, blood tests, and medical imaging, and confirmed by biopsy of the temporal artery. However, in about 10% of people the temporal artery is normal. Treatment is typical with high doses of steroids such as prednisone or prednisolone. Once symptoms have resolved, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Causality
Causality is an influence by which one Event (philosophy), event, process, state, or Object (philosophy), object (''a'' ''cause'') contributes to the production of another event, process, state, or object (an ''effect'') where the cause is at least partly responsible for the effect, and the effect is at least partly dependent on the cause. The cause of something may also be described as the reason for the event or process. In general, a process can have multiple causes,Compare: which are also said to be ''causal factors'' for it, and all lie in its past. An effect can in turn be a cause of, or causal factor for, many other effects, which all lie in its future. Some writers have held that causality is metaphysics , metaphysically prior to notions of time and space. Causality is an abstraction that indicates how the world progresses. As such it is a basic concept; it is more apt to be an explanation of other concepts of progression than something to be explained by other more fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
