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Pterygium
Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits. The term comes from the Greek word ''pterygion'' meaning "wing". Types * Popliteal pterygium syndrome, a congenital condition affecting the face, limbs, or genitalia but named after the wing-like structural anomaly behind the knee * Pterygium (eye) or surfer's eye, a growth on the cornea of the eye * Pterygium colli or webbed neck, a congenital skin fold of the neck down to the shoulders * Pterygium inversum unguis or ventral pterygium, adherence of the distal portion of the nailbed to the ventral surface of the nail plate * Pterygium unguis Pterygium unguis (or dorsal pterygiumFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) forms as a result of scarring between the proximal nailfold and matrix, with the classic example being liche ... or dorsal pterygium, scarring betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium (eye)
A pterygium of the eye (plural ''pterygia'' or ''pterygiums'', also called surfer's eye) is a pinkish, roughly triangular tissue growth of the conjunctiva onto the cornea of the eye. It typically starts on the cornea near the nose. It may slowly grow but rarely grows so large that it covers the pupil and impairs vision. Often both eyes are involved. The cause is unclear. It appears to be partly related to long term exposure to UV light and dust. Genetic factors also appear to be involved. It is a benign growth. Other conditions that can look similar include a pinguecula, tumor, or Terrien's marginal corneal degeneration. Prevention may include wearing sunglasses and a hat if in an area with strong sunlight. Among those with the condition, an eye lubricant can help with symptoms. Surgical removal is typically only recommended if the ability to see is affected. Following surgery a pterygium may recur in around half of cases. The frequency of the condition varies from 1% t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium Slitlamp
Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits. The term comes from the Greek word ''pterygion'' meaning "wing". Types * Popliteal pterygium syndrome, a congenital condition affecting the face, limbs, or genitalia but named after the wing-like structural anomaly behind the knee * Pterygium (eye) or surfer's eye, a growth on the cornea of the eye * Pterygium colli or webbed neck, a congenital skin fold of the neck down to the shoulders * Pterygium inversum unguis or ventral pterygium, adherence of the distal portion of the nailbed to the ventral surface of the nail plate * Pterygium unguis Pterygium unguis (or dorsal pterygiumFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) forms as a result of scarring between the proximal nailfold and matrix, with the classic example being liche ... or dorsal pterygium, scarring betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium
Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits. The term comes from the Greek word ''pterygion'' meaning "wing". Types * Popliteal pterygium syndrome, a congenital condition affecting the face, limbs, or genitalia but named after the wing-like structural anomaly behind the knee * Pterygium (eye) or surfer's eye, a growth on the cornea of the eye * Pterygium colli or webbed neck, a congenital skin fold of the neck down to the shoulders * Pterygium inversum unguis or ventral pterygium, adherence of the distal portion of the nailbed to the ventral surface of the nail plate * Pterygium unguis Pterygium unguis (or dorsal pterygiumFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) forms as a result of scarring between the proximal nailfold and matrix, with the classic example being liche ... or dorsal pterygium, scarring betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Popliteal Pterygium Syndrome
Popliteal pterygium syndrome (PPS) is an heredity, inherited condition affecting the face, Limb (anatomy), limbs, and genitalia. The syndrome goes by a number of names including the ''popliteal web syndrome'' and, more inclusively, the ''facio-genito-popliteal syndrome''. The term PPS was coined by Gorlin ''et al.'' in 1968 on the basis of the most unusual Birth defect, anomaly, the popliteal pterygium (a web behind the knee). Symptoms and signs Medical sign, Clinical expressions of PPS are highly variable, but include the following: * Limb (anatomy), Limb findings: an extensive web running from behind the knee down to the heel (90%), malformed toenails, and webbed toes. * face, Facial findings: cleft palate with or without cleft lip (75%), pits in the lower lip (40%), fibrous bands in the mouth known as syngnathia (25%), and tissue connecting the upper and lower eyelids * genitalia, Genital findings (50%): hypoplasia of the labia majora, malformation of the scrotum, and cryptorch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium Inversum Unguis
Pterygium inversum unguis or ventral pterygium is characterized by the adherence of the distal portion of the nailbed to the ventral surface of the nail plate.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . The condition may be present at birth or acquired, and may cause pain with manipulation of small objects, typing, and close manicuring of the nail. secondary due to connective tissue disorders See also * Pterygium unguis * Nail (anatomy), Nail * List of cutaneous conditions References Conditions of the skin appendages {{skin-appendage-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium Colli
A webbed neck, or pterygium colli, is a congenital skin fold that runs along the sides of the neck down to the shoulders. There are many variants. Signs and symptoms On babies, webbed neck may look like loose folds of skin on the neck. As the child grows, the skin may stretch out to look like there is little or no neck. Associated conditions It is a feature of Turner syndrome (only found in girls) and Noonan syndrome, as well as the rarer Klippel–Feil syndrome, or Diamond–Blackfan anemia Diamond–Blackfan anemia (DBA) is a congenital erythroid aplasia that usually presents in infancy. DBA causes low red blood cell counts (anemia), without substantially affecting the other blood components (the platelets and the white blood cel ... References External links {{Congenital malformations and deformations of ear, face and neck Congenital disorders of eye, ear, face and neck ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterygium Unguis
Pterygium unguis (or dorsal pterygiumFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) forms as a result of scarring between the proximal nailfold and matrix, with the classic example being lichen planus, though it has been reported to occur as a result of sarcoidosis and Hansen's disease.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. . See also * Pterygium inversum unguis * Nail (anatomy), Nail * List of cutaneous conditions References Conditions of the skin appendages {{skin-appendage-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is approximately 43 dioptres. The cornea can be reshaped by surgical procedures such as LASIK. While the cornea contributes most of the eye's focusing power, its focus is fixed. Accommodation (the refocusing of light to better view near objects) is accomplished by changing the geometry of the lens. Medical terms related to the cornea often start with the prefix "'' kerat-''" from the Greek word κέρας, ''horn''. Structure The cornea has unmyelinated nerve endings sensitive to touch, temperature and chemicals; a touch of the cornea causes an involuntary reflex to close the eyelid. Because transparency is of prime importance, the healthy cornea does not have or need blood vessels with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Eye
The human eye is a sensory organ, part of the sensory nervous system, that reacts to visible light and allows humans to use visual information for various purposes including seeing things, keeping balance, and maintaining circadian rhythm. The eye can be considered as a living optical device. It is approximately spherical in shape, with its outer layers, such as the outermost, white part of the eye (the sclera) and one of its inner layers (the pigmented choroid) keeping the eye essentially light tight except on the eye's optic axis. In order, along the optic axis, the optical components consist of a first lens (the cornea—the clear part of the eye) that accomplishes most of the focussing of light from the outside world; then an aperture (the pupil) in a diaphragm (the iris—the coloured part of the eye) that controls the amount of light entering the interior of the eye; then another lens (the crystalline lens) that accomplishes the remaining focussing of light into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Membrane Biology
Membrane biology is the study of the biological and physiochemical characteristics of membranes, with applications in the study of cellular physiology. Membrane bioelectrical impulses are described by the Hodgkin cycle. Biophysics Membrane biophysics is the study of biological membrane structure and function using physical, computational, mathematical, and biophysical methods. A combination of these methods can be used to create phase diagrams of different types of membranes, which yields information on thermodynamic behavior of a membrane and its components. As opposed to membrane biology, membrane biophysics focuses on quantitative information and modeling of various membrane phenomena, such as lipid raft The plasma membranes of cells contain combinations of glycosphingolipids, cholesterol and protein receptors organised in glycolipoprotein lipid microdomains termed lipid rafts. Their existence in cellular membranes remains somewhat controversial. ... formation, rates of l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
