Congenital cataracts and children

August 12, 2017 17:51 | Genetic Diseases

Cataract - a partial or complete opacification of the substance or the lens capsule, which is accompanied by a decrease in visual acuity up to complete its loss.Cataract is the main cause of blindness in the world.

term « congenital cataract » means cataract already at birth.Clouding of the lens during the 1st year of life is called the children's cataracts.Some lens opacity remain undetected at birth, and they are found only at the time of the survey, so the terms are often considered equivalent.Congenital cataracts and children occur at a frequency of 1 in 2000 newborns.

Congenital cataracts and children may be bilateral (85%) or one-sided.As a rule, children 1/3 congenital cataracts or combined with other diseases (such as Down syndrome, Hallerman Shtrayffa-Francois syndrome, Lowe syndrome, Marfan syndrome, Alport syndrome).1/3 of all cases of congenital cataracts and child occurs as a hereditary disease, which in most cases is transmitted in an autosomal dominant inheritance type.Furthermore, the

re is the likelihood of disease transmission in an autosomal recessive, X-linked type.In 1/3 of the formation of cataracts cause remains unknown.Metabolic diseases (diabetes, galactosemia, hypocalcemia, Westphal disease, Wilson's, myotonic dystrophy) usually combined with bilateral cataracts.

Intrauterine infection (rubella, cytomegalovirus infection, chicken pox, herpes, syphilis, toxoplasmosis) may also be a cause of congenital cataracts.

Rubella in a pregnant woman can cause damage to the fetus, particularly when infected in the first three months of pregnancy.Systemic manifestations of congenital rubella include heart disease, deafness and mental retardation.Cataract as a result of congenital rubella syndrome appears pearly white haze kernel eyes.Sometimes a cataract formed complete with thinning of the upper layers of the lens.Live virus particles can be separated from the lens of the child 3 years after birth.Cataract surgery can be complicated by excessive postoperative inflammation caused by virus release.Other ocular manifestations of congenital rubella syndrome: retinal pigment loss, involuntary movements of the eyeballs, reducing the size of the eye, glaucoma, cloud-corneal opacity.Although congenital rubella syndrome that may be causing and cataracts and glaucoma, simultaneous development of these conditions is not typical in one eye.The defeat of the body with rubella reaches 49-53%.

Manifestations cataract depends on its type.When polar cataract in the lens changes lead to clouding of the lens capsule layers.Front polar cataracts is typically a small bilateral symmetric non-progressive clouding does not decrease the visual acuity.Anterior polar cataracts are sometimes found in combination with other ocular abnormalities (reduction in size of the eyeball, the remains of the pupillary membrane and front lenticonus).Rear polar cataracts generally results in a greater reduction of visual acuity than the front.In most cases, it is stable and rarely progresses.

Cataracts can be the first to arise or family.Family posterior polar cataract usually affects both eyes and is transmitted in an autosomal dominant inheritance type.First emerged back polar cataract usually affects only one organ of vision and can be combined with the defeat of the lens or its capsule abnormality such as lenticonus.

Seam or stellate cataracts rarely leads to vision loss.Bilateral and symmetrical suture cataracts often transmitted in an autosomal dominant inheritance type.

Congenital nuclear cataract usually affects both eyes, the intensity of the lens opacities may be different.The eyeball with congenital cataract nuclear typically reduced in size.

Capsular cataracts - this is a limited anterior lens capsule opacification.Capsular Cataract usually not adversely affect the sight.

Zonulyarnaya or layered cataract is the most simple form of congenital cataract.This bilateral symmetric loss.Turbidity is caused by short-term toxic effects during embryonic growth of the lens.Layered cataracts can be transmitted in an autosomal dominant inheritance type.

laminated cataract - clouding of the lens of specific layers or zones, that is revealed in a special survey.

Full cataract is a clouding of the lens in all.Some cataracts may be partial at birth and progress rapidly to complete opacification of the lens.Full cataract may be unilateral or bilateral and leads to a significant decrease in vision.

filmy cataract occurs when resorption of proteins from whole or injured lens.The front and rear lens capsule are soldered together into a solid white membrane.Opacification and lens distortion in this case is the immediate cause of a significant decrease in visual acuity.