degeneration
[de-gen″ĕ-ra´shun] deterioration; change from a higher to a lower form, especially change of tissue to a lower or less functionally active form. When there is chemical change of the tissue itself, it is true degeneration; when the change consists in the deposit of abnormal matter in the tissues, it is infiltration. adj., adj degen´erative.
cerebromacular degeneration (
cerebroretinal degeneration)
1. degeneration of brain cells and of the macula retinae, as occurs in
tay-sachs disease.
2. any lipidosis with cerebral lesions and degeneration of the retinal macula.
colloid degeneration degeneration with conversion of the tissues into a gelatinous or gumlike material.
cystic degeneration degeneration with formation of cysts.
fatty degeneration deposit of fat globules in a tissue.
hyaline degeneration a regressive change in cells in which the cytoplasm takes on a homogeneous, glassy appearance; also used loosely to describe the histologic appearance of tissues.
hydropic degeneration a form in which the epithelial cells absorb much water.
lattice degeneration of retina a frequently bilateral, usually benign asymptomatic condition, characterized by patches of fine gray or white lines that intersect at irregular intervals in the peripheral retina, usually associated with numerous, round, punched-out areas of retinal thinning or retinal holes.
mucoid degeneration degeneration with deposit of myelin and lecithin in the cells.
mucous degeneration degeneration with accumulation of mucus in epithelial tissues.
myofibrillar degeneration damage to selective cardiac cells when surrounding interstitial cells, nerves, and capillaries remain viable.
spongy degeneration of central nervous system (
spongy degeneration of white matter)
Canavan disease.
subacute combined degeneration of spinal cord degeneration of both the posterior and lateral columns of the spinal cord, producing various motor and sensory disturbances; it is due to vitamin B
12 deficiency and is usually associated with pernicious anemia. Called also
Lichtheim's or
Putnam-Dana syndrome.
wallerian degeneration fatty degeneration of a nerve fiber that has been severed from its nutritive source.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.