background preloader

Clinical significance and diseases of the Eye

Facebook Twitter

Macular degeneration. Macular degeneration, often age-related macular degeneration (AMD or ARMD), is a medical condition that usually affects older adults and results in a loss of vision in the center of the visual field (the macula) because of damage to the retina.

Macular degeneration

It occurs in "dry" and "wet" forms. It is a major cause of blindness and visual impairment in older adults (>50 years). Macular degeneration can make it difficult or impossible to read or recognize faces, although enough peripheral vision remains to allow other activities of daily life. Although some macular dystrophies affecting younger individuals are sometimes referred to as macular degeneration, the term generally refers to age-related macular degeneration (AMD or ARMD). The retina is a network of visual receptors and nerves. In the dry (nonexudative) form, cellular debris called drusen accumulates between the retina and the choroid, and the retina can become detached.

Signs and symptoms[edit] Signs and symptoms of macular degeneration include: Myopia. Myopia (Ancient Greek: μυωπία, muōpia, from myein "to shut (like a mole - mys/mus in Greek)" – ops (gen. opos) "eye, look, sight"[1]) literally meaning "trying to see like a mole" (mys/mus), commonly known as near-sightedness (American English) and short-sightedness (British English), is a condition of the eye where the light that comes in does not directly focus on the retina but in front of it, causing the image that one sees when looking at a distant object to be out of focus, but in focus when looking at a close object.

Myopia

When used colloquially, 'myopia' can also refer to a view on or way of thinking about something which is—by extension of the medical definition—hyper-focused and fails to include a larger context beyond the focus. The opposite of myopia is hyperopia (long-sightedness). Classification[edit] By cause[edit] Borish and Duke-Elder classified myopia by cause:[3][4] Clinical entity[edit] Various forms of myopia have been described by their clinical appearance:[4][7][8] Cause[edit]

Asthenopia. Asthenopia (aesthenopia) from the Greek word "asthen-opia : ασθεν-ωπία" or eye strain is an ophthalmological condition that manifests itself through nonspecific symptoms such as fatigue, pain in or around the eyes, blurred vision, headache and occasional double vision.

Asthenopia

Symptoms often occur after reading, computer work, or other close activities that involve tedious visual tasks. When concentrating on a visually intense task, such as continuously focusing on a book or computer monitor, the ciliary muscle tightens. This can cause the eyes to get irritated and uncomfortable.

Giving the eyes a chance to focus on a distant object at least once an hour usually alleviates the problem. A CRT computer monitor with a low refresh rate (<70Hz) or a CRT television can cause similar problems because the image has a visible flicker. Causes[edit] See also[edit]

Eye care professionals

Eye irritation. Eye disease. Eye injury. A small piece of iron has lodged near the margin of the cornea Eye injury by impact of small plastic body.

Eye injury

Physical or chemical injuries of the eye can be a serious threat to vision if not treated appropriately and in a timely fashion. The most obvious presentation of ocular (eye) injuries is redness and pain of the affected eyes. This is not, however, universally true, as tiny metallic projectiles may cause neither symptom. Tiny metallic projectiles should be suspected when a patient reports metal on metal contact, such as with hammering a metal surface. Causes[edit] Flicking sand, flying pieces of wood, metal, glass, stone and other material are notorious for causing much of the eye trauma. Effects of eye injury[edit] Epidemiology[edit] Investigation[edit] The goal of investigation is the assessment of the severity of the ocular injury with an eye to implementing a management plan as soon as is required. Emergency[edit] An emergency must be treated within minutes. Urgent[edit] Patching[edit] Eye disease.