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21 Cards in this Set
- Front
- Back
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An optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image on the retina. This may be due to an irregular or toric curvature of the cornea or lens.
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Astigmatism
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is a clouding that develops in the crystalline lens of the eye or in its envelope, varying in degree from slight to complete opacity and obstructing the passage of light. Early in the development of age-related cataract the power of the lens may be increased, causing near-sightedness (myopia), and the gradual yellowing and opacification of the lens may reduce the perception of blue colours. Cataracts typically progress slowly to cause vision loss and are potentially blinding if untreated. The condition usually affects both the eyes, but almost always one eye is affected earlier than the other.
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Cataracts
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- color vision deficiency, is the inability to perceive differences between some of the colors that others can distinguish. It is most often of genetic nature, but may also occur because of eye, nerve, or brain damage, or exposure to certain chemicals. The normal human retina contains two kinds of light cells: the rod cells (active in low light) and the cone cells (active in normal daylight). Normally, there are three kinds of cones, each containing a different pigment, which are activated when the pigments absorb light. The absorption spectra of the cones differ; one is maximally sensitive to short wavelengths, one to medium wavelengths, and the third to long wavelengths. Red light, for example, stimulates the long wavelength cones much more than either of the others, and reducing the wavelength causes the other two cone systems to be increasingly stimulated, causing a gradual change in hue.
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Color Blindness
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An acute inflammation of the conjunctiva (the outermost layer of the eye and the inner surface of the eyelids), most commonly due to an allergic reaction or an infection (usually viral, but sometimes bacterial (pink eye).
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Conjunctivitis
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(damage to the retina) caused by complications of diabetes mellitus, which can eventually lead to blindness. It is an ocular manifestation of systemic disease which affects up to 80% of all patients who have had diabetes for 10 years or more.[1] Despite these intimidating statistics, research indicates that at least 90% of these new cases could be reduced if there was proper and vigilant treatment and monitoring of the eyes
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Diabetic retinopathy
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A set of neuropathic disorders that are associated with diabetes mellitus. These conditions are thought to result from diabetic microvascular injury involving small blood vessels that supply nerves (vasa nervorum). Diabetic neuropathy affects all peripheral nerves: pain fibers, motor neurons, autonomic nerves. It therefore necessarily can affect all organs and systems since all are innervated. Symptoms usually develop gradually over years.
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Diabetic neuropathy
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Commonly known as double vision, is the simultaneous perception of two images of a single object. These images may be displaced horizontally, vertically, or diagonally (i.e. both vertically and horizontally) in relation to each other.
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Diplopia
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A disease in which the optic nerve is damaged, leading to progressive, irreversible loss of vision. It is often, but not always, associated with increased pressure of the fluid in the eye. The nerve damage involves loss of retinal ganglion cells in a characteristic pattern. The loss of vision normally occurs gradually over a long period of time and is often only recognized when the disease is quite advanced. Glaucoma affects 1 in 200 people aged fifty and younger, and 1 in 10 over the age of eighty. If the condition is detected early enough it is possible to arrest the development or slow the progression with medical and surgical means.
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Glaucoma
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Also known as farsightedness, is a defect of vision caused by an imperfection in the eye (often when the eyeball is too short. or when the lens cannot become round enough), causing difficulty focusing on near objects, and in extreme cases causing a sufferer to be unable to focus on objects at any distance.
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Hyperopia
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A disorder of the inner ear that can affect hearing and balance to a varying degree. It is characterized by episodes of dizziness and tinnitus and progressive hearing loss, usually in one ear. It is caused by lymphatic channel dilation,[2] affecting the drainage of endolymph. The condition affects people differently; it can range in intensity from being a mild annoyance to a chronic, lifelong disability.
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Meniere’s disease
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Nearsightedness, is a refractive defect of the eye in which collimated light produces image focus in front of the retina when accommodation is relaxed. Those with myopia see near objects clearly but far away objects appear blurred. With myopia, the eyeball is too long, or the cornea is too steep, so images are focused in the vitreous inside the eye rather than on the retina at the back of the eye.
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Myopia
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A condition making it difficult or impossible to see in relatively low light. It is a symptom of several eye diseases. Night blindness may exist from birth, or be caused by injury or malnutrition (for example, a lack of vitamin A). The most common cause of nyctalopia is retinitis pigmentosa, a disorder in which the rod cells in the retina gradually lose their ability to respond to the light
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Nyctalopia
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Inflammation of the middle ear, or middle ear infection. Otitis media occurs in the area between the ear drum (the end of the outer ear) and the inner ear, including a duct known as the eustachian tube. It is one of the two categories of ear inflammation that can underlie what is commonly called an earache.
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Otitis media
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An abnormal growth of bone near the middle ear. It can result in hearing loss. This usually will begin in one ear but will eventually affect both ears with a variable course. Approximately 0.5% of the population will eventually be diagnosed with otosclerosis.
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Otosclerosis
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Age-related hearing loss, is the cumulative effect of aging on hearing. Also known as presbyacusis, it is defined as a progressive bilateral symmetrical age-related sensorineural hearing loss. The hearing loss is most marked at higher frequencies.
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Presbycusis
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A health condition where the eye exhibits a progressively diminished ability to focus on near objects with age.
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Presbyopia
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(sometimes referred to as reflective pain) is a term used to describe the phenomenon of pain perceived at a site adjacent to or at a distance from the site of an injury's origin. One of the best examples of this is during ischemia brought on by a myocardial infarction (heart attack) where pain is often felt in the neck, shoulders, and back rather than in the chest, the site of the injury.
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Referred pain
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A condition in which the eyes are not properly aligned with each other.[2] It typically involves a lack of coordination between the extraocular muscles that prevents bringing the gaze of each eye to the same point in space and preventing proper binocular vision, which may adversely affect depth perception. Strabismus can be either a disorder of the brain in coordinating the eyes, or of one or more of the relevant muscles' power or direction of motion.
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Strabismus
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the perception of sound within the human ear in the absence of corresponding external sound. Tinnitus is not a disease; but a symptom resulting from a range of underlying causes that can include: ear infections, foreign objects or wax in the ear, nose allergies that prevent (or induce) fluid drain and cause wax build-up. Tinnitus can also be caused by natural hearing impairment (as in aging), as a side-effect of some medications, and as a side-effect of genetic (congenital) hearing loss. However, the most common cause for tinnitus is noise-induced hearing loss.
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Tinnitus
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A type of dizziness, where there is a feeling of motion when one is stationary.[2] The symptoms are due to a dysfunction of the vestibular system in the inner ear.[2] It is often associated with nausea and vomiting as well as difficulties standing or walking.
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Vertigo
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Acuteness or clearness of vision, especially form vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain. VA is a quantitative measure of the ability to identify black symbols on a white background at a standardized distance as the size of the symbols is varied. It is the most common clinical measurement of visual function. (i.e.20/20 vision)
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Visual acuity
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