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Orthoptics
Orthoptics is a profession allied to the eye care profession. Orthoptists are the experts in diagnosing and treating defects in eye movements and problems with how the eyes work together, called binocular vision. These can be caused by issues with the muscles around the eyes or defects in the nerves enabling the brain to communicate with the eyes. Orthoptists are responsible for the diagnosis and non-surgical management of strabismus (cross-eyed), amblyopia (lazy eye) and eye movement disorders.International Orthoptic Association document "professional role" The word ''orthoptics'' comes from the Greek words ὀρθός ''orthos'', "straight" and ὀπτικός ''optikοs'', "relating to sight" and much of the practice of orthoptists concerns disorders of binocular vision and defects of eye movement. Orthoptists are trained professionals who specialize in orthoptic treatment, such as eye patches, eye exercises, prisms or glasses. They commonly work with paediatric patients and also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vision Therapy
Vision therapy (VT), or behavioral optometry, is an umbrella term for alternative medicine treatments using eye exercises, based around the pseudoscientific claim that vision problems are the true underlying cause of learning disabilities, particularly in children. Vision therapy has not been shown to be effective using scientific studies, except for helping with convergence insufficiency. Most claimsfor example that the therapy can address neurological, educational, and spatial difficultieslack supporting evidence. Neither the American Academy of Pediatrics nor the American Academy of Ophthalmology support the use of vision therapy. Definition and conceptual basis Vision therapy is based on the proposition that many learning disabilities in children are based on vision problems, and that these can be cured by performing eye exercises. Vision therapy lacks sound evidence, has been characterized as a pseudoscience and its practice as quackery. Vision therapy is a broad concept t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haploscope
A haploscope is an optical device for presenting one image to one eye and another image to the other eye. The word derives from two Greek roots: ''haploieides'', single and ''skopeo'', to view. The word is often used interchangeably with stereoscope, but it is more general than that. A stereoscope is a type of haploscope, but not vice versa. The word has more currency in the medical field than elsewhere, where it refers to instruments designed to test binocular vision. These instruments include Worth's amblyoscope and the synoptophore. Commonly haploscopes employ front-surfaced mirrors placed at different angles close to the eyes to reflect the images into the eyes. Reputedly the largest haploscope, with images of over a meter (in fact, 4 feet) square and a viewing distance for each eye of nearly five meters (16 feet), was constructed by Vaegan in about 1975 to research stereoacuity. The large images allowed very small retinal disparities to be presented. See also * Che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phoropter
A phoropter or refractor is an ophthalmic testing device. It is commonly used by eye care professionals during an eye examination, and contains different lenses used for refraction of the eye during sight testing, to measure an individual's refractive error and determine their eyeglass prescription.Dictionary.comDefinition of "phoropter" American Heritage Stedman's Medical Dictionary. Retrieved 10-10-1/ref> It also is used to measure the patients' Heterophoria, phorias and ductions, which are characteristics of binocularity. Typically, the patient sits behind the phoropter, and looks through it at an eye chart placed at optical infinity (20 feet or 6 metres), then at near (16 inches or 40 centimetres) for individuals needing reading glasses. The eye care professional then changes lenses and other settings, while asking the patient for subjective feedback on which settings gave the best vision. The patient's habitual prescription or an automated refractor may be used to pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Convergence Insufficiency
Convergence insufficiency is a sensory and neuromuscular anomaly of the binocular vision system, characterized by a reduced ability of the eyes to turn towards each other, or sustain convergence. Symptoms The symptoms and signs associated with convergence insufficiency are related to prolonged, visually demanding, near-centered tasks. They may include, but are not limited to, diplopia (double vision), asthenopia (eye strain), transient blurred vision, difficulty sustaining near-visual function, abnormal fatigue, headache, and abnormal postural adaptation, among others. In some cases, difficulty with making eye contact have been noted as a complaint amongst those affected. Note that some Internet resources confuse convergence and divergence dysfunction, reversing them. Diagnosis Diagnosis of convergence insufficiency is made by an eye care professional skilled in binocular vision dysfunctions, such as an orthoptist, to rule out any organic disease. Convergence insufficiency is chara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pediatric Ophthalmology
Pediatric ophthalmology is a sub-speciality of ophthalmology concerned with eye diseases, visual development, and vision care in children. Training In the United States, pediatric ophthalmologists are physicians who have completed medical school, a 1-year internship, 3-year residency in ophthalmology, and a 1-year fellowship in pediatric ophthalmology and strabismus. Pediatric ophthalmology fellowships in the United States are accredited by the American Association for Pediatric Ophthalmology and Strabismus. Clinical expertise Pediatric ophthalmologists focus on the development of the visual system and the various diseases that disrupt visual development in children. Pediatric ophthalmologists also have expertise in managing the various ocular diseases that affect children. Pediatric ophthalmologists are qualified to perform complex eye surgery as well as to manage children's eye problems using glasses and medications. Many ophthalmologists and other physicians refer pediatric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eye Care Professional
An eye care professional (ECP) is an individual who provides a service related to the eyes or vision. It is any healthcare worker involved in eye care, from one with a small amount of post-secondary training to practitioners with a doctoral level of education. Types Ophthalmologist Ophthalmologists are Doctors of Medicine (M.D./D.O.)(physicians) who specialize in eye care - this includes optical, medical and surgical eye care. They have a general medical degree, not a degree in eye care specifically.” In the US, this usually includes four years of college, four years of medical school, one year surgical internship and three years of eye specific training (ophthalmology residency). Some surgeons complete additional training (fellowship) in specific areas of the eye. Ophthalmologists are qualified to manage any eye disease, perform invasive eye surgery (including injections) and provide general medical care (non eye related) also. While Ophthalmologists can provide comprehensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissociated Vertical Deviation
Dissociated vertical deviation (DVD) is an eye condition which occurs in association with a squint, typically infantile esotropia. The exact cause is unknown, although it is logical to assume it is from faulty innervation of eye muscles. Presentation The eye drifts upward spontaneously or after being covered. The condition usually affects both eyes, but can occur unilaterally or asymmetrically. It is often associated with latent or manifest-latent nystagmus and, as well as occurring with infantile esotropia, can also be found associated with exotropias and vertical deviations. DVDs are usually controlled from occurring with both eyes open, but may become manifest with inattention. Usually some level of dissociative occlusion is required - to trigger the brain to suppress vision in that eye and then not control a DVD from occurring. The level of dissociative occlusion required may involve using a red filter, a darker filter or complete occlusion (e.g. with a hand). Onset DVD typi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplopia
Diplopia is the simultaneous perception of two images of a single object that may be displaced horizontally or vertically in relation to each other. Also called double vision, it is a loss of visual focus under regular conditions, and is often voluntary. However, when occurring involuntarily, it results in impaired function of the extraocular muscles, where both eyes are still functional, but they cannot turn to target the desired object. Problems with these muscles may be due to mechanical problems, disorders of the neuromuscular junction, disorders of the cranial nerves ( III, IV, and VI) that innervate the muscles, and occasionally disorders involving the supranuclear oculomotor pathways or ingestion of toxins. Diplopia can be one of the first signs of a systemic disease, particularly to a muscular or neurological process, and it may disrupt a person's balance, movement, or reading abilities. Causes Diplopia has a diverse range of ophthalmologic, infectious, autoimmune, neu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractive Error
Refractive error, also known as refraction error, is a problem with focus (optics), focusing light accurately on the retina due to the shape of the human eye, eye and or cornea. The most common types of refractive error are myopia, near-sightedness, hyperopia, far-sightedness, astigmatism, and presbyopia. Near-sightedness results in far away objects being blurred vision, blurry, far-sightedness and presbyopia result in close objects being blurry, and astigmatism causes objects to appear stretched out or blurry. Other symptoms may include double vision, headaches, and eye strain. Near-sightedness is due to the length of the eyeball being too long, far-sightedness the eyeball too short, astigmatism the cornea being the wrong shape, and presbyopia aging of the lens of the eye such that it cannot change shape sufficiently. Some refractive errors occur more often among those whose parents are affected. Diagnosis is by eye examination. Refractive errors are corrected with eyeglasses, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strabismus
Strabismus is a vision disorder in which the eyes do not properly align with each other when looking at an object. The eye that is focused on an object can alternate. The condition may be present occasionally or constantly. If present during a large part of childhood, it may result in amblyopia, or lazy eyes, and loss of depth perception. If onset is during adulthood, it is more likely to result in double vision. Strabismus can occur due to muscle dysfunction, farsightedness, problems in the brain, trauma or infections. Risk factors include premature birth, cerebral palsy and a family history of the condition. Types include esotropia, where the eyes are crossed ("cross eyed"); exotropia, where the eyes diverge ("lazy eyed" or "wall eyed"); and hypertropia or hypotropia where they are vertically misaligned. They can also be classified by whether the problem is present in all directions a person looks (comitant) or varies by direction (incomitant). Diagnosis may be made by obser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinhole Glasses
Pinhole glasses, also known as stenopeic glasses, are eyeglasses with a series of pinhole-sized perforations filling an opaque sheet of plastic in place of each lens. Similar to the workings of a pinhole camera, each perforation allows only a very narrow beam of light to enter the eye which reduces the size of the circle of confusion on the retina and increases depth of field. In eyes with refractive error, the result is often a sharper image. However, a second effect may appear at the common bridge between each two adjacent holes, whereby two different rays of light coming from the same object (but each passing through a different hole) are diffracted back toward the eye and onto different places on the retina. Unlike conventional prescription glasses, pinhole glasses produce an image without the pincushion effect around the edges (which makes straight lines appear curved). While pinhole glasses are claimed to be useful for people who are both near- and far-sighted, they are not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eyepatch
An eyepatch is a small patch that is worn in front of one eye. It may be a cloth patch attached around the head by an elastic band or by a string, an adhesive bandage, or a plastic device which is clipped to a pair of glasses. It is often worn by people to cover a lost or injured eye, but it also has a therapeutic use in children for the treatment of amblyopia. Eyepatches used to block light while sleeping are referred to as a sleep mask. An eyepad or eye pad is a soft medical dressing that can be applied over an eye to protect it. It is not necessarily the same as an eyepatch. History In the years before advanced medicine and surgery, eyepatches were common for people who had a lost or injured eye. They were particularly prevalent among members of dangerous occupations, such as soldiers and sailors who could lose an eye in battle. While stereotypically associated with pirates, there is no evidence to suggest the historical accuracy of eye patch wearing pirates before severa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
