nuclear cataract

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Related to hard cataract: Cataract surgery, Extracapsular cataract extraction

nu·cle·ar cat·a·ract

a cataract involving the nucleus.
Synonym(s): hard cataract

nu·cle·ar cat·a·ract

(nū'klē-ăr kat'ăr-akt)
A cataract involving the nucleus of the lens.

nuclear cataract

, nuclear sclerotic c.
A cataract in which the central portion of the lens is opacified.
See also: cataract

cataract

opacity of the lens of the eye or its capsule or both. Cataract may result from injuries to the eye, exposure to great heat or radiation, or inherited factors. Rare in cattle and swine, common in dogs. Treatment consists of surgical removal of the lens (lens extraction or cataract extraction). May affect the entire lens or be localized, e.g. posterior polar cataract.

acquired cataract
any non-congenital cataract; usually the result of trauma, systemic disease or another eye disorder.
after-cataract
1. any membrane of the pupillary area after extraction or absorption of the lens.
2. secondary cataract (below).
capsular cataract
one consisting of an opacity of the capsule of the lens.
complicated cataract
a cataract occurring secondarily to other intraocular disease.
congenital cataract
present at birth; often not progressive. See also white eye calf syndrome.
cortical cataract
an opacity in the cortex of the lens. The common form of cataract in dogs; inherited in many breeds, often in association with progressive retinal atrophy.
developmental cataract
one that occurs at any age before the animal becomes an adult.
diabetic cataract
one associated with diabetes mellitus.
electric cataract
one caused by electrical current as in electrocution.
embryonal cataract
one caused by prenatal influences.
focal ring cataract
a perinuclear opacity with normal lens fibers surrounding it. Usually the result of an in utero or neonatal insult to the lens.
galactosemic cataract
hyaloid cataract
a focal opacity at the point where the hyaloid artery meets the posterior lens capsule. See also mittendorf's dot.
hypermature cataract
one in which the lens has begun to liquefy.
immature cataract
incomplete opacity.
incipient cataract
a very early stage of development with no impairment of vision.
inherited cataract
occurs in a number of breeds of cattle, often in combination with other abnormalities of the eye. Affected calves are usually normal in other respects and can be reared if the inconvenience of their blindness can be overcome. Also occurs in dogs, often with late onset and in association with other inherited ocular defects such as progressive retinal atrophy.
intumescent cataract
a mature cataract that has become swollen.
juvenile cataract
one developing in very young animals, for example dogs less than 6 months of age.
lenticular cataract
opacity of the lens not affecting the capsule.
mature cataract
one in which the lens is completely opaque.
morgagnian cataract
liquefaction, except the nucleus which drops to the bottom of the lens, and shrinkage of the capsule.
nuclear cataract
one involving the nucleus of the lens; the common form of congenital cataracts.
nuclear Y cataract
a form of congenital cataract in which small opacities outline the Y suture of the nucleus.
nutritional cataract
radiation cataract
one caused by radiation, as in radiotherapy.
reduplication cataract
a capsular opacity covered by another layer of epithelium.
secondary cataract
1. one that forms after most of the lens has been removed.
2. complicated cataract.
senile cataract
occurs in the aged of all species, preceded by nuclear sclerosis.
subcapsular cataract
may be anterior or posterior. Inherited in several breeds of dogs.
toxic cataract
one caused by exposure to a toxic substance.
traumatic cataract
one caused by trauma.