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Lagophthalmos
Lagophthalmos is the inability to close the eyelids completely.Cline D; Hofstetter HW; Griffin JR. ''Dictionary of Visual Science''. 4th ed. Butterworth-Heinemann, Boston 1997. Blinking covers the eye with a thin layer of tear fluid, thereby promoting a moist environment necessary for the cells of the exterior part of the eye. The tears also flush out foreign bodies and wash them away, which is crucial to maintain lubrication and proper eye health. If this process is impaired, as in lagophthalmos, the eye can suffer abrasions and infections; thus leading to corneal drying and ulceration. Type(s) Nocturnal lagophthalmos is the inability to close the eyelids during sleep. It may reduce the quality of sleep, cause exposure-related symptoms or, if severe, cause corneal damage ( exposure keratopathy). The degree of lagophthalmos can be minor (obscure lagophthalmos) or quite obvious. It is often caused by an anomaly of the eyelid that prevents full closure. Treatment may involve surge ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exposure Keratopathy
Exposure keratopathy (also known as exposure keratitis) is medical condition affecting the cornea of eyes. It can lead to corneal ulceration and permanent loss of vision due to corneal opacity. Normally, corneal surface is kept moist by blinking. During sleep, it is covered by lids. Increased corneal exposure to the air due to incomplete or inadequate eyelid closure cause increased evaporation of tears from corneal surface. Increased evaporation of tears causes instability of the tear film and dryness of corneal surface. This will lead to corneal epithelial damage. Both tear film and corneal epithelium play significant role in corneal protection. The dryness and epithelial damage allows micro-organisms to penetrate the cornea and thus keratitis occurs. Signs and symptoms Symptoms are similar to dry eye. Patients may complain redness, irritation, ocular discomfort, burning, and foreign body sensation. Punctate epithelial defects, epithelial break down and stromal melting may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facial Nerve
The facial nerve, also known as the seventh cranial nerve, cranial nerve VII, or simply CN VII, is a cranial nerve that emerges from the pons of the brainstem, controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue. The nerve typically travels from the pons through the facial canal in the temporal bone and exits the skull at the stylomastoid foramen. It arises from the brainstem from an area posterior to the cranial nerve VI (abducens nerve) and anterior to cranial nerve VIII (vestibulocochlear nerve). The facial nerve also supplies preganglionic parasympathetic fibers to several head and neck ganglia. The facial and intermediate nerves can be collectively referred to as the nervus intermediofacialis. The path of the facial nerve can be divided into six segments: # intracranial (cisternal) segment (from brainstem pons to internal auditory canal) # meatal (canalicular) segment (with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blepharoplasty
Blepharoplasty (Greek: ''blepharon'', "eyelid" + ''plassein'' "to form") is the plastic surgery operation for correcting defects, deformities, and disfigurations of the eyelids; and for aesthetically modifying the eye region of the face. With the excision and the removal, or the repositioning (or both) of excess tissues, such as skin and adipocyte fat, and the reinforcement of the corresponding muscle and tendon tissues, the blepharoplasty procedure resolves functional and cosmetic problems of the periorbita, which is the area from the eyebrow to the upper portion of the cheek. The procedure is more common among women, who accounted for approximately 85% of blepharoplasty procedures in 2014 in the US and 88% of such procedures in the UK. The operative goals of a blepharoplastic procedure are the restoration of the correct functioning to the affected eyelid(s) and the restoration of the aesthetics of the eye-region of the face, which are achieved by eliminating excess skin from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eyelid
An eyelid ( ) is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral" (and "blepharal") means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist. They keep the eyes from drying out when asleep. Moreover, the blink reflex protects the eye from foreign bodies. A set of specialized hairs known as lashes grow from the upper and lower eyelid margins to further protect the eye from dust and debris. The appearance of the human upper eyelid often varies between different populations. The prevalence of an epicanthic fold covering the inner corner of the eye account for the majority of East Asian and Southeast Asian populations, and is also found in varying degrees among other populat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blinking
Blinking is a bodily function; it is a semi-autonomic rapid closing of the eyelid. A single blink is determined by the forceful closing of the eyelid or inactivation of the levator palpebrae superioris and the activation of the palpebral portion of the orbicularis oculi, not the full open and close. It is an essential function of the eye that helps spread tears across and remove irritants from the surface of the cornea and conjunctiva. Blinking may have other functions since it occurs more often than necessary just to keep the eye lubricated. Researchers think blinking may help with disengagement of attention; following blink onset, cortical activity decreases in the dorsal network and increases in the default-mode network, associated with internal processing. Blink speed can be affected by elements such as fatigue, eye injury, medication, and disease. The blinking rate is determined by the "blinking center", but it can also be affected by external stimulus. Some animals, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corneal Ulceration
Corneal ulcer, often resulting from keratitis is an inflammatory or, more seriously, infective condition of the cornea involving disruption of its epithelial layer with involvement of the corneal stroma. It is a common condition in humans particularly in the tropics and in farming. In developing countries, children afflicted by vitamin A deficiency are at high risk for corneal ulcer and may become blind in both eyes persisting throughout life. In ophthalmology, a corneal ulcer usually refers to having an infection, while the term corneal abrasion refers more to a scratch injury. Types Superficial and deep corneal ulcers Corneal ulcers are a common human eye disease. They are caused by trauma, particularly with vegetable matter, as well as chemical injury, contact lenses and infections. Other eye conditions can cause corneal ulcers, such as entropion, distichiasis, corneal dystrophy, and keratoconjunctivitis sicca (dry eye). Many micro-organisms cause infective corneal ulcer. Am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Punctal Plug
A punctal plug, also known as tear duct plug or lacrimal plug, is a small medical device that is inserted into the Nasolacrimal duct, tear duct (puncta) of an human eye, eye to block the duct. This prevents the drainage of liquid from the eye. They are used to treat Keratoconjunctivitis sicca, dry eye. Artificial tears are usually still required after punctal plug insertion. Types A temporary punctal occlusion can be inserted and tried first. These are made of collagen and are dissolvable. This is to ascertain that permanent ones will not cause excessive tearing (lacrimation). Permanent punctal plugs are usually made of silicone. These are available in various sizes. For maximum effectiveness, the largest size that fits should be used. These are more effective than collagen plugs. They can sometimes become loose and fall out, in which case they can be replaced. Some plugs are made of thermally reactive material. Some of these are inserted into the punctum as a liquid, and then ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
US Airways
US Airways was a major airline in the United States. It was originally founded in History of aviation in Pittsburgh, Pittsburgh as a mail delivery airline called All American Aviation, which soon became a commercial passenger airline. In 1953, it was renamed Allegheny Airlines and operated under that name for a quarter-century. In October 1979, after the passage of the Airline Deregulation Act, Allegheny Airlines changed its name to USAir. A decade later it had acquired Piedmont Airlines (1948–1989), Piedmont Airlines and Pacific Southwest Airlines (PSA), and was one of the U.S.'s seven transcontinental legacy carriers. In 1997, it rebranded as US Airways. The airline had an extensive international and domestic network, with 193 destinations in 24 countries in North America, South America, Europe, and the Middle East. The airline was a member of the Star Alliance, before becoming an affiliate member of Oneworld in March 2014. US Airways had 343 mainline (flight), mainline jets, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosis
Ichthyosis is a family of genetic disorder, genetic skin disorders characterized by Xeroderma, dry, Scleroderma, thickened, scaly skin. The more than 20 types of ichthyosis range in severity of symptoms, outward appearance, underlying genetic cause and mode of inheritance (e.g., Dominance (genetics), dominant, recessive, autosomal or X-linked). Ichthyosis comes , since dry, scaly skin is the defining feature of all forms of ichthyosis. The severity of symptoms can vary enormously, from the mildest, most common, types such as ichthyosis vulgaris, which may be mistaken for normal dry skin, up to life-threatening conditions such as harlequin-type ichthyosis. Ichthyosis vulgaris accounts for more than 95% of cases. Types Many types of ichthyoses exist, and an exact diagnosis may be difficult. Types of ichthyoses are classified by their appearance, if they are syndromic or not, and by mode of inheritance. For example, non-syndromic ichthyoses that are inherited recessively come under ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tarsorrhaphy
Tarsorrhaphy is a surgical procedure in which the eyelids are partially sewn together to narrow the eyelid opening. It may be done to protect the cornea in cases of corneal exposure, as a treatment for Graves' ophthalmopathy, Möbius syndrome or after corneal graft surgery. The procedure is performed on the corner of the eyelid opening. See also * Eye surgery Eye surgery, also known as ophthalmic surgery or ocular surgery, is surgery performed on the eye or its adnexa. Eye surgery is part of ophthalmology and is performed by an ophthalmologist or eye surgeon. The eye is a fragile organ, and require ... * Keratoconjunctivitis sicca References External links Surgery Encyclopedia: Tarsorrhaphy Oculoplastic surgery {{treatment-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hare
Hares and jackrabbits are mammals belonging to the genus ''Lepus''. They are herbivores and live Solitary animal, solitarily or in pairs. They nest in slight depressions called forms, and their young are precociality, able to fend for themselves shortly after birth. The genus includes the largest Lagomorpha, lagomorphs. Most are fast runners with long, powerful hind legs, and large ears that dissipate body heat. Hare species are native to Africa, Eurasia and North America. A hare less than one year old is called a "leveret". Members of the ''Lepus'' genus are considered true hares, distinguishing them from rabbits which make up the rest of the Leporidae family. However, there are five leporid species with "hare" in their common names which are not considered true hares: the hispid hare (''Caprolagus hispidus''), and four species known as red rock hares (''Pronolagus''). Conversely, several ''Lepus'' species are called "jackrabbits", but classed as hares rather than rabbits. The p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
