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Sympathetic Ophthalmia
Sympathetic ophthalmia (SO), also called spared eye injury, is a diffuse granulomatous inflammation of the uveal layer of both eyes following trauma to one eye. It can leave the affected person completely blind. Symptoms may develop from days to several years after a penetrating eye injury. It typically results from a delayed hypersensitivity reaction. Signs and symptoms Eye floaters and loss of accommodation are among the earliest symptoms. The disease may progress to severe inflammation of the uveal layer of the eye (uveitis) with pain and sensitivity of the eyes to light. The affected eye often remains relatively painless while the inflammatory disease spreads through the uvea, where characteristic focal infiltrates in the choroid named Dalén–Fuchs nodules can be seen. The retina, however, usually remains uninvolved, although perivascular cuffing of the retinal vessels with inflammatory cells may occur. Swelling of the optic disc (papilledema), secondary glaucoma, vitil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floaters
Floaters or eye floaters are sometimes visible deposits (e.g., the shadows of tiny structures of protein or other cell debris projected onto the retina) within the eye's vitreous humour ("the vitreous"), which is normally transparent, or between the vitreous and retina.Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Butterworth-Heinemann, Boston 1997. They can become particularly noticeable when looking at a blank surface or an open monochromatic space, such as blue sky. Each floater can be measured by its size, shape, consistency, refractive index, and motility. They are also called ''muscae volitantes'' (Latin for 'flying flies'), or ''mouches volantes'' (from the same phrase in French). The vitreous usually starts out transparent, but imperfections may gradually develop as one ages. The common type of floater, present in most people's eyes, is due to these degenerative changes of the vitreous. The perception of floaters, which may be annoying o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanin
Melanin (; from el, μέλας, melas, black, dark) is a broad term for a group of natural pigments found in most organisms. Eumelanin is produced through a multistage chemical process known as melanogenesis, where the oxidation of the amino acid tyrosine is followed by polymerization. The melanin pigments are produced in a specialized group of cells known as melanocytes. Functionally, eumelanin serves as protection against Ultraviolet, UV radiation. There are five basic types of melanin: eumelanin, pheomelanin, neuromelanin, allomelanin and pyomelanin. The most common type is eumelanin, of which there are two types— brown eumelanin and black eumelanin. Pheomelanin, which is produced when melanocytes are malfunctioning due to derivation of the gene to its recessive format is a cysteine-derivative that contains polybenzothiazine portions that are largely responsible for the of red yellow tint given to some skin or hair colors. Neuromelanin is found in the brain. Research ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ciclosporin
Ciclosporin, also spelled cyclosporine and cyclosporin, is a calcineurin inhibitor, used as an immunosuppressant medication. It is a natural product. It is taken orally or intravenously for rheumatoid arthritis, psoriasis, Crohn's disease, nephrotic syndrome, and in organ transplants to prevent rejection. It is also used as eye drops for keratoconjunctivitis sicca (dry eyes). Common side effects include high blood pressure, headache, kidney problems, increased hair growth, and vomiting. Other severe side effects include an increased risk of infection, liver problems, and an increased risk of lymphoma. Blood levels of the medication should be checked to decrease the risk of side effects. Use during pregnancy may result in preterm birth; however, ciclosporin does not appear to cause birth defects. Ciclosporin is believed to work by decreasing the function of lymphocytes. It does this by forming a complex with cyclophilin to block the phosphatase activity of calcineurin, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclophosphamide
Cyclophosphamide (CP), also known as cytophosphane among other names, is a medication used as chemotherapy and to suppress the immune system. As chemotherapy it is used to treat lymphoma, multiple myeloma, leukemia, ovarian cancer, breast cancer, small cell lung cancer, neuroblastoma, and sarcoma. As an immune suppressor it is used in nephrotic syndrome, granulomatosis with polyangiitis, and following organ transplant, among other conditions. It is taken by mouth or injection into a vein. Most people develop side effects. Common side effects include low white blood cell counts, loss of appetite, vomiting, hair loss, and bleeding from the bladder. Other severe side effects include an increased future risk of cancer, infertility, allergic reactions, and pulmonary fibrosis. Cyclophosphamide is in the alkylating agent and nitrogen mustard family of medications. It is believed to work by interfering with the duplication of DNA and the creation of RNA. Cyclophosphamide was appr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorambucil
Chlorambucil, sold under the brand name Leukeran among others, is a chemotherapy medication used to treat chronic lymphocytic leukemia (CLL), Hodgkin lymphoma, and non-Hodgkin lymphoma. For CLL it is a preferred treatment. It is given by mouth. Common side effects include bone marrow suppression. Other serious side effects include an increased long term risk of further cancer, infertility, and allergic reactions. Use during pregnancy often results in harm to the baby. Chlorambucil is in the alkylating agent family of medications. It works by blocking the formation of DNA and RNA. Chlorambucil was approved for medical use in the United States in 1957. It is on the World Health Organization's List of Essential Medicines. It was originally made from nitrogen mustard. Medical uses Chlorambucil's current use is mainly in chronic lymphocytic leukemia, as it is well tolerated by most patients, though chlorambucil has been largely replaced by fludarabine as first-line treatment in you ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mydriasis
Mydriasis is the dilation of the pupil, usually having a non-physiological cause, or sometimes a physiological pupillary response. Non-physiological causes of mydriasis include disease, trauma, or the use of certain types of drugs. Normally, as part of the pupillary light reflex, the pupil dilates in the dark and constricts in the light to respectively improve vividity at night and to protect the retina from sunlight damage during the day. A ''mydriatic'' pupil will remain excessively large even in a bright environment. The excitation of the radial fibres of the iris which increases the pupillary aperture is referred to as a mydriasis. More generally, mydriasis also refers to the natural dilation of pupils, for instance in low light conditions or under sympathetic stimulation. Fixed, unilateral mydriasis could be a symptom of raised intracranial pressure. The opposite, constriction of the pupil, is referred to as miosis. Both mydriasis and miosis can be physiological. Anisocori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corticosteroids
Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are involved in a wide range of physiological processes, including stress response, immune response, and regulation of inflammation, carbohydrate metabolism, protein catabolism, blood electrolyte levels, and behavior. Some common naturally occurring steroid hormones are cortisol (), corticosterone (), cortisone () and aldosterone (). (Note that cortisone and aldosterone are isomers.) The main corticosteroids produced by the adrenal cortex are cortisol and aldosterone. Classes * Glucocorticoids such as cortisol affect carbohydrate, fat, and protein metabolism, and have anti-inflammatory, immunosuppressive, anti-proliferative, and vasoconstrictive effects. Anti-inflammatory effects are mediated by blocking the action of inflammatory mediators ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunosuppressive Therapy
Immunosuppression is a reduction of the activation or efficacy of the immune system. Some portions of the immune system itself have immunosuppressive effects on other parts of the immune system, and immunosuppression may occur as an adverse reaction to treatment of other conditions. In general, deliberately induced immunosuppression is performed to prevent the body from rejecting an organ transplant. Additionally, it is used for treating graft-versus-host disease after a bone marrow transplant, or for the treatment of auto-immune diseases such as systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, or Crohn's disease. This is typically done using medications, but may involve surgery (splenectomy), plasmapheresis, or radiation. A person who is undergoing immunosuppression, or whose immune system is weak for some other reasons (such as chemotherapy or HIV), is said to be ''immunocompromised''. Deliberately induced Administration of immunosuppressive medi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extraocular Muscles
The extraocular muscles (extrinsic ocular muscles), are the seven extrinsic muscles of the human eye. Six of the extraocular muscles, the four recti muscles, and the superior and inferior oblique muscles, control movement of the eye and the other muscle, the levator palpebrae superioris, controls eyelid elevation. The actions of the six muscles responsible for eye movement depend on the position of the eye at the time of muscle contraction. Structure Since only a small part of the eye called the fovea provides sharp vision, the eye must move to follow a target. Eye movements must be precise and fast. This is seen in scenarios like reading, where the reader must shift gaze constantly. Although under voluntary control, most eye movement is accomplished without conscious effort. Precisely how the integration between voluntary and involuntary control of the eye occurs is a subject of continuing research."eye, human."Encyclopædia Britannica from Encyclopædia Britannica 2006 Ulti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evisceration (ophthalmology)
An evisceration is the removal of the eye's contents, leaving the scleral shell and extraocular muscles intact.Cassin, B. and Solomon, S. ''Dictionary of Eye Terminology''. Gainesville, Florida: Triad Publishing Company, 1990.Zein W"Evisceration, Enucleation, and Exenteration." Eyeweb.org. Accessed September 25, 2006. The procedure is usually performed to reduce pain or improve cosmesis in a blind eye, as in cases of endophthalmitis unresponsive to antibiotics. An ocular prosthetic can be fitted over the eviscerated eye in order to improve cosmesis. Ocularist Association of California. Accessed September 25, 2006. Either or |
Enucleation Of The Eye
Enucleation is the removal of the eye that leaves the eye muscles and remaining orbital contents intact. This type of ocular surgery is indicated for a number of ocular tumors, in eyes that have sustained severe trauma, and in eyes that are otherwise blind and painful. Self-enucleation or auto-enucleation (oedipism) and other forms of serious self-inflicted eye injury are an extremely rare form of severe self-harm that usually results from mental illnesses involving acute psychosis. The name comes from Oedipus of Greek mythology, who gouged out his own eyes. Classification There are three types of eye removal: * Evisceration – removal of the iris, cornea, and internal eye contents, but with the sclera and attached extraocular muscles left behind * Enucleation of the eye - removal of the eyeball, but with the eyelids and adjacent structures of the eye socket remaining. An intraocular tumor excision requires an enucleation, not an evisceration. * Exenteration – removal of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
