|
Retinoscope
Retinoscopy (Ret) is a technique to obtain an objective measurement of the refractive error of a patient's eyes. The examiner uses a retinoscope to shine light into the patient's eye and observes the reflection (reflex) off the patient's retina. While moving the streak or spot of light across the pupil the examiner observes the relative movement of the reflex or manually places lenses over the eye (using a trial frame and trial lenses) to "neutralize" the reflex. Static retinoscopy is a type of retinoscopy used in determining a patient's refractive error. It relies on Foucault knife-edge test, which states that the examiner should simulate optical infinity to obtain the correct refractive power. Hence, a power corresponding to the working distance is subtracted from the gross retinoscopy value to give the patient's refractive condition, the working distance lens being one which has a focal length of the examiner's distance from the patient (e.g. +1.50 dioptre lens for a 67 cm w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmoscope
Ophthalmoscopy, also called funduscopy, is a test that allows a health professional to see inside the fundus of the eye and other structures using an ophthalmoscope (or funduscope). It is done as part of an eye examination and may be done as part of a routine physical examination. It is crucial in determining the health of the retina, optic disc, and vitreous humor. The pupil is a hole through which the eye's interior will be viewed. Opening the pupil wider (dilating it) is a simple and effective way to better see the structures behind it. Therefore, dilation of the pupil ( mydriasis) is often accomplished with medicated eye drops before funduscopy. However, although dilated fundus examination is ideal, undilated examination is more convenient and is also helpful (albeit not as comprehensive), and it is the most common type in primary care. An alternative or complement to ophthalmoscopy is to perform a fundus photography, where the image can be analysed later by a professional. ... [...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] |
Eye Examination
An eye examination is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations pertaining to the eyes. Eye examinations are primarily performed by an optometrist, ophthalmologist, or an orthoptist. Health care professionals often recommend that all people should have periodic and thorough eye examinations as part of routine primary care, especially since many eye diseases are asymptomatic. Eye examinations may detect potentially treatable blinding eye diseases, ocular manifestations of systemic disease, or signs of tumours or other anomalies of the brain. A full eye examination consists of an external examination, followed by specific tests for visual acuity, pupil function, extraocular muscle motility, visual fields, intraocular pressure and ophthalmoscopy through a dilated pupil. A minimal eye examination consists of tests for visual acuity, pupil function, and extraocular muscle motility, as w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthoptist
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] |
Optometrist
Optometry is a specialized health care profession that involves examining the eyes and related structures for defects or abnormalities. Optometrists are health care professionals who typically provide comprehensive primary eye care. In the United States and Canada, optometrists are those that hold a Doctor of Optometry degree. They are trained and licensed to practice medicine for eye related conditions, in addition to providing refractive (optical) eye care. In the United Kingdom, optometrists may also practice medicine (and provide refractive care) for eye related conditions. The Doctor of Optometry title can also be used in the UK for those that hold the postgraduate O.D. degree. Within their scope of practice, optometrists are considered physicians and bill medical insurance(s) (example: Medicare) accordingly. Moreover, many participate in academic research for eye related conditions and disease. Optometrists are the only health care professionals with a first professional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmologist
Ophthalmology ( ) is a surgery, surgical subspecialty within medicine that deals with the diagnosis and treatment of eye disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Following a medical degree, a doctor specialising in ophthalmology must pursue additional postgraduate residency (medicine), residency training specific to that field. This may include a one-year integrated internship that involves more general medical training in other fields such as internal medicine or general surgery. Following residency, additional specialty training (or fellowship) may be sought in a particular aspect of eye pathology. Ophthalmologists prescribe medications to treat eye diseases, implement laser therapy, and perform surgery when needed. Ophthalmologists provide both primary and specialty eye care - medical and surgical. Most ophthalmologists participate in academic research on eye diseases at some point in their training an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dispensing Optician
An optician, or ''dispensing optician'', is a technical practitioner who designs, fits and dispenses lenses for the correction of a person's vision. Opticians determine the specifications of various Ophthalmology, ophthalmic appliances that will give the necessary correction to a person's eyesight. Some registered or licensed opticians also design and fit special appliances to correct cosmetic, traumatic or anatomical defects. These devices are called shells or Ocular prosthesis, artificial eyes. Other registered or licensed opticians manufacture lenses to their own specifications and design and manufacture spectacle frames and other devices. Corrective ophthalmic appliances may be contact lenses, spectacles lenses, low vision aids or ophthalmic prosthetics to those who are partially sighted. The appliances are mounted either on the eye as contact lenses or mounted in a frame or holder in front of the eye as spectacles or as a monocle. Opticians may work in any variety of setti ... [...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] |
Red Reflex
The red reflex refers to the reddish-orange reflection of light from the back of the eye, or fundus, observed when using an ophthalmoscope or retinoscope. The reflex relies on the transparency of optical media (tear film, cornea, aqueous humor, crystalline lens, vitreous humor) and reflects off the fundus back through media into the aperture of the ophthalmoscope. The red reflex is considered abnormal if there is any asymmetry between the eyes, dark spots, or white reflex (Leukocoria). Generally, it is a physical exam done on neonates and children by healthcare providers but occasionally occurs in flash photography seen when the pupil does not have enough time to constrict and reflects the fundus known as the red-eye effect. This is a recommended screening by the American Academy of Pediatrics and American Academy of Family Physicians for neonates and children at every office visit. The objective is to detect ocular pathology that needs early intervention and ophthalmology refe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocular Estimate Method
The monocular estimate method or monocular estimation method is a form of dynamic retinoscopy widely used to objectively measure accommodative response.Tassinari JT. "Monocular estimate method retinoscopy: central tendency measures and relationship to refractive status and heterophoria." ''Optom Vis Sci.'' 2002 Nov;79(11):708-14. .Taub MB, Rowe S, Bartuccio M"Examining special populations. Part 3: Examination techniques." ''OT.'' March 10, 2006. Accessed October 2, 2006. Values normally attained when performing MEM are between +0.25 and +0.50 diopter A dioptre (British spelling) or diopter (American spelling) is a unit of measurement with dimension of reciprocal length, equivalent to one reciprocal metre, 1 dioptre = 1 m−1. It is normally used to express the optical power of a lens or cur ...s. References Ophthalmology {{eye-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accommodation (eye)
Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image or focus on an object as its distance varies. In this, distances vary for individuals from the far point—the maximum distance from the eye for which a clear image of an object can be seen, to the near point—the minimum distance for a clear image. Accommodation usually acts like a reflex, including part of the accommodation-vergence reflex, but it can also be consciously controlled. Mammals, birds and reptiles vary their eyes' optical power by changing the form of the elastic lens using the ciliary body (in humans up to 15 dioptres in the mean). Fish and amphibians vary the power by changing the distance between a rigid lens and the retina with muscles. The young human eye can change focus from distance (infinity) to as near as 6.5 cm from the eye. This dramatic change in focal power of the eye of approximately 15 dioptres (the reciprocal of focal length in metres) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Eyes
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] |
.svg "Click for more on -> Accommodation (eye)")
