wallerian degeneration

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.caseous degeneration caseation (def. 2).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.3. any form of neuronal ceroid-lipofuscinosis.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.fibroid degeneration degeneration of a leiomyoma" >leiomyoma with subsequent fibrosis" >fibrosis.hepatolenticular degeneration Wilson's disease.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.macular degeneration see macular degeneration.macular degeneration, congenital see stargardt's disease.macular degeneration, Stargardt's stargardt's disease.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.myxomatous degeneration mucous degeneration.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 B₁₂ 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.Zenker's degeneration Zenker's necrosis.

wal·le·ri·an de·gen·er·a·tion

the degenerative changes the distal segment of a peripheral nerve fiber (axon and myelin) undergoes when its continuity with its cell body is interrupted by a focal lesion.