|
| | |
Myopia
Myopia Also known as nearsightedness, myopia is a refractive error caused by an eyeball that is too long to focus light on the retina or a cornea which is too steeply curved. In these cases light focuses instead in front of the retina. People with myopia are usually able to see close objects well, but objects in the distance—such as highway signs or writing on a chalkboard—appear blurred.
RELATED TERMS--------------------------------------
Nearsightedness
Focusing defect in which the eye is overpowered. Light rays coming from a distant object are brought to focus before reaching the retina. Requires a minus lens correction to "weaken" the eye optically and permit clear distance vision.
Myopia
Also known as nearsightedness, myopia is a refractive error caused by an eyeball that is too long to focus light on the retina or a cornea which is too steeply curved. In these cases light focuses instead in front of the retina. People with myopia are usually able to see close objects well, but objects in the distance—such as highway signs or writing on a chalkboard—appear blurred.
Retina
A membrane lining the inside of the back of the eye that contains light-sensitive nerve cells that convert focused light into nerve impulses, making vision possible.
Cornea
The front part of the eye that acts as a window for the entrance of light rays. It is attached to the other outer coat of the eye, the sclera; the white part of the eye. The cornea provides a significant amount of focusing power for the eye (the rest is provided by the lens). Because it has many nerve fibers, an injury or foreign body causes significant pain and discomfort.
SIMILAR TERMS--------------------------------------
PREVIOUS AND NEXT TERMS--------------------------------------
Macular degeneration
Damage or breakdown of the macula, which is an area in the back of the eye that controls central vision. It may be caused by injury or aging; and while it does not progress to total blindness, patients with macular degeneration require special optical aids to enlarge distant and near objects.
Monocular vision
A condition in which one eye is blind, or in which one eye refuses to register images in co-ordination with the better eye.
Multiple sclerosis
An auto-immune disease of the central nervous system, mainly affecting young adults, whose origin is unknown. It damages nerve fiber insulation (myelin) in a random and patchy manner, causing a wide range of neurological defects. It is characterized clinically by symptoms that typically abate spontaneously in the early years of the disease but often get gradually worse in later years.
Muscular dystrophy
An inherited condition that is due to a gene on the X chromosome. It is therefore called a sex-linked gene. It results in the inability to produce a vital muscle chemical resulting in muscle wastage, stumbling, then inability to walk and death by the age of about 20.
Myasthenia gravis (MG)
Myasthenia gravis is a neuromuscular disease in which there is a failure of the nerves' ability to stimulate and control the actions of certain muscles, especially those of the eye, face, lips, tongue, throat, and neck.
Myopia
Meniere's Disease
A disorder or condition of the inner ear. The major symptoms that cause most of our difficulty are characterized by abnormal sensation of movement (vertigo), loss of hearing, and noises or ringing (tinnitus) in one or both ears. was first described by French physician Prosper Meniere in 1861.
Myositis
Muscular soreness due to inflammation that often occurs 1-2 days after unaccustomed exercise. Often referred as DOMS (Delayed onset muscle soreness).
Metatarsus
The metatarsus consists of the five long bones of the foot, which are numbered from the medial side (ossa metatarsalia I.-V.); each presents for examination a body and two extremities. These are analogous to the metacarpals of the hand.
Metacarpals
Five long bones of the hand, running from the wrist to the fingers.
Metacarpus
The metacarpus is the intermediate part of the hand skeleton that is located between the fingers distally and the carpus which forms the connection to the forearm. It consists of five cylindrical bones which are numbered from the radial to the ulnar side (ossa metacarpalia I-V); each consists of a body and two extremities.
We thank you for using the Health Dictionary to search for Myopia. If you have a better definition for Myopia than the one presented here, please let us know by making use of the suggest a term option. This definition of Myopia may be disputed by other professionals. Our attempt is to provide easy definitions on Myopia and any other medical topic for the public at large.This dictionary contains 25007 terms. |
|
|
