![]() ![]() Light is therefore essential to the development of visual function. But the duration of occlusion required lengthens with age and if treatment begins at age 5, recovery will be incomplete and fragile, despite prolonged occlusion. Similarly, strabismic amblyopia can be easily treated at nine months with temporary occlusion of short duration and an appropriate optical correction. Fitting aphakic infants with contact lenses allows them to acquire normal vision. A baby presenting early lens opacity should be operated on during the first months of life to prevent severe amblyopia. The existence of this sensitive period in humans is now widely recognized. Numerous visual deprivation experiments conducted in baby monkeys and kittens show attrition of visual pathways due to vision deprivation, making it possible to define a “deprivation-sensitive period”. Light plays a fundamental role in this visual performance. This relative slowness facilitates examination. Ocular motor control, including saccades and pursuit, is precise at one year, although latency or reaction time is characterized by a certain slowness up to the age of about ten. Stereoscopic vision appears at four months and rapidly becomes excellent.įocusing becomes precise at about eight months with the development of the fovea in which the cones are gradually concentrated, enabling a reliable orthoptic examination. This is evidenced by the large proportion of motorists who do not use the rear-view mirror.Ĭolour and contrast vision is good at three months, but will continue to improve until adolescence. The field of vision is complete at one year but the child needs to learn to use it, a process that will continue more or less successfully throughout life, depending on motivation. ![]() At the age of six months, their acuity reaches 2/10, and then 4/10 at one year and 10/10 at about five years of age, remember-ing that in preverbal children we measure detection acuity with acuity cards and then the more demanding morphoscopic acuity. For their comfort, strong light should be avoided. This enables us to measure their acuity, which is about 1/20.ĭepending on their complexion (very light or more pigmented), they are dazzled by light up to the age of about six months. But if they are awakened in a low-light environment, they will look at us. If newborns quite often keep their eyes closed, it may be because they are asleep. When we laterally illuminate a pregnant woman’s womb around the sixth month of pregnancy, we can see under ultrasound that the foetus turns its head away from the light source. ![]() The newborn child can see from the moment of birth, and even before. ![]()
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