(1) 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.

(2) Med. deterioration in structure or function of cells, tissues, or organs, as in disease or aging

Cloudy swelling, an early stage of degenerative change characterized by swollen, parboiled-appearing tissues which revert to normal when the cause is removed.

Wallerian degeneration affecting centripetal nerve fibers and progressing toward the brain or spinal cord.

Swelling of the cytoplasm in epidermal cells without vacuolization, enlarged or condensed nuclei and acantholysis. A characteristic of viral infections of the skin. Called also koilocytosis.

Degeneration of tissue with deposit of calcareous material.

Caseation (2). necrosis in which tissue is changed into a dry mass resembling cheese.

(CMD), cerebroretinal degeneration 1. degeneration of brain cells and of the macula retinae. 2. any lipidosis with cerebral lesions and degeneration of the macula retinae. 3. any form of neuronal ceroid-lipofuscinosis.

Degeneration with conversion of the tissues into a gelatinous or gumlike material.

Hereditary macular degeneration with a cystlike lesion that in the early stages resembles egg yolk.

Crooke's hyalinization. Crooke's hyaline degeneration Crooke's hyalinization.

Degeneration with formation of cysts.

Wallerian degeneration extending peripherally along nerve fibers.

A form of macular degeneration seen in persons over age 40, in which sclerosis involving the macula and retina is produced by hemorrhages between Bruch's membrane and the pigment epithelium.

Deposit of fat globules in a tissue.

Said of hepatocytes; a hydropic change in hepatocytes which have suffered long-term exposure to cholestasis.

Deposition or replacement with eosinophilic fibrillar or granular substance resembling fibrin.

Degeneration into fibrous tissue.

Necrosis with deposit of fibrin within the cells of the tissue.

Degeneration of the white substance of the spinal cord, in which it loses myelin and assumes a gray color.

Wilson's disease. an inherited, progressive disorder of copper metabolism, with accumulation of copper in liver, brain, kidney, cornea, and other tissues; it is characterized by cirrhosis in the liver, degenerative changes in the brain, and a pigmented ring at the outer margin of the cornea.

A regressive change in cells in which the cytoplasm takes on a homogeneous, glassy appearance; also used loosely to describe the histological appearance of tissues. Called also hyalinosis.

Calcareous degeneration degeneration of tissue with deposit of calcareous material.

Of retina an often bilateral, usually benign asymptomatic condition, characterized by patches of fine gray or white intersecting lines in the peripheral retina, usually with numerous round punched-out areas of retinal thinning or retinal holes.

Degenerative changes in the macula retinae.

Degeneration with increased mucin which can be epithelial or mesenchymal in origin.

Degeneration with accumulation of mucus in epithelial tissues. Called also myxomatous degeneration.

Degeneration in which mucus accumulates in connective tissues. see mucous degeneration (above).

Extreme intracellular edema of epidermal cells, resulting in rupture and multilocular intraepidermal vesicles with septae formed by the remaining cell walls. Seen in acute inflammatory dermatoses.

On microscopic examination has the physical appearance of a sponge. Usually applied to tissue of the central nervous system, caused by the loss of myelin.

A rare hereditary form of leukodystrophy of early onset in which widespread demyelination and vacuolation of cerebral white matter gives it a spongy appearance; there is mental retardation, megalocephaly, atony of neck muscles, limb spasticity, and blindness, with death in infancy.

Of white a rare hereditary form of leukodystrophy of early onset in which widespread demyelination and vacuolation of cerebral white matter gives it a spongy appearance; there is mental retardation, megalocephaly, atony of neck muscles, limb spasticity, and blindness, with death in infancy.

A form of multiple system atrophy with nerve cell degeneration mainly in the region of the substantia nigra and the neostriatum; symptoms are similar to those of parkinsonism.

Of spinal cord degeneration of posterior and lateral columns of the spinal cord, with various motor and sensory disturbances; it is due to vitamin B12 deficiency and usually associated with pernicious anemia.

Degeneration of the pigmented layer of the retina.

Atrophy of certain neurons after interruption of afferent axons or death of other neurons to which they send their efferent output.

Hyaline degeneration and necrosis of striated muscle.