Parents need to pay attention to children's common eye illness

Parents need to pay attention to children's common eye illness
Eyeball development
The normal eyeball takes shape, need to pass a succession of growth, development course. The eye doctor says, split up through complicated cells, when the little embryo is in the parent is big in about 4 weeks, the eyeball has already begun development; Thereafter, the development of the eyeball wall, with the sclera, cornea, retina, and an inner refracting media such as crystalline lens, vitreous body,etc. are developed successively, even if intact eyeball takes shape.
The doctor points out, the baby just born, eyeball development was only sixty percent of adult's eyeball; The infant of about 3 years old, the eyes function can reach ninety percent of ordinary persons; Reach 6 years old at the latest, structure and function can equate adult's standard.
Know the eyeball structure to liken with concrete articles, " eyeball " Construct like one. The camera " ,Cornea, crystalline lens can be compared to the camera " The lens " ; The iris equates with " The diaphragm " ; The vitreous body is equivalent to " The dark place " ; Retina look like the intersection of human body and the sensitization of camera " The film " .
Eyesight develops, walk unhurriedly and grow up
The neonate because retinal macula lutea department development has not been complete yet, mommies can find, baby that born just, scarce and " firm to look at " Ability.
The doctor says, small Baby one month old, has already to stimulate had the response to the light, how much has already looked at ability preliminarily and firmly; It is 3 months old to invite, the eyeball be able to follow objects to move slowly while beginning: Invite 5- 6 months old, firm to look at, track it is kind for ability to become, begin, appear the intersection of hand and eyes coordinate, try to stretch out one's hand and touch objects.
Develop into 3 year old all the way, can let baby carry on regular eyesight check; Invite during 6 years old, including eyeball structure and eyesight are developed, even if development is complete; And already totally finalized the design to 10 years old, the child's optic nerve development at the latest.
In front of the location of cornea is on the eyeball the most, accept the first amazing door of external light source. The crystalline lens is an elastic transparent body, the location is after iris and pupil, before the vitreous body, function is refracted in order to regulate the light.
See nearly thing, ciliary muscle shrink, it is thick for crystalline lens to; While watching the distant place, extend the ciliary muscle, the crystalline lens becomes thin, the light refracts and diminishes. The iris and main function of pupil are to responsible for regulating the light and entering the eyeball. Similar " diaphragm " Function. The iris will be changed according to the light of the surrounding environment, control the sphincter of pupil and enlarge the skin, when the light is strong, the pupil shrinks, " diaphragm " Diminish; On the contrary, when the light is dark, platycoria, " diaphragm " Become great.
The vitreous body is body of a transparent colloid, lie will produce certain strength (a intraocular pressure) behind the eyeball ,Prop up the eyeball outside inside, in order to keep the eyeball shape. Retina lie behind the eyeball, structure and like " film " of camera function Generally, light and color will penetrate the route transmission of the retina, optic nerve, entry lies in brain occipital lobe " The visual centre " ,Let us must use " The eyes are seen in order to need " !
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