Baby Eye Care or Infant Vision
At birth the pigment color-making iris cells aren’t fully developed. For this reason, a baby’s eyes are lightest at birth and gradually darken during the first 12 months as the iris thickens and takes on its genetically determined color.
The clarity of a new born baby’s vision corresponds to about 20/400 on the Snellen acuity chart, or is about 7-8 lines less accurate than that of an adult with good vision. During the first two months of life a baby can only focus on objects more than 10 inches or 25 cm from her face. A newborn baby seeks bold, large patterns, generally in black, red, and white, when she looks at objects around her and is able to perceive motion. By approximately 5 months the baby should have developed color vision.
Eye-hand coordination as early as 5-6 weeks, when a baby starts tracking objects in his near milieu and attempts to reach them with his hands, is a vital stimulator of vision development. At about 2 months, babies begin to focus their eyes on the faces of people around them, preferentially a parent. However, the infant’s eyes are not yet well-coordinated when he views objects distant or near and may sometimes give a cross-eyed appearance. Strabismus or inability of the visual pathways in the brain and the eye muscles to coordinate the simultaneous use of the eyes is normal in infants until about 3 months of age.
If signs of strabismus or cross-eyed looking are still present at this age, there is an increased risk for refractive asymmetry in later years. Basic motor skills such as hand-eye coordination at this stage of development and crawling as well as walking later in the first year of life can be affected by squint or strabismus. A visit to an optometrist or orthoptic specialist should be scheduled to assess the child’s binocular vision capacity if difficulty in coordinating eye movement still exists beyond the third month.
When children become more physically active and start to roll and lift their upper bodies, binocular vision and the ability to focus start developing more rapidly. The baby’s attempts to grab objects and move them to his mouth aids both the ocular muscles and visual pathways in strengthening visual acuity, resulting in vision as sharp as 20/40 at six months.
At this age, depth perception begins to evolve rapidly as the child’s ability to judge distances improves and general visual perceptual skills are refined. However, if the child has a squint during the first year of life, depth perception will not develop fully, even if the child’s motor ability progresses normally during the transition from crawling to walking. As many as 4% of children under the age of 6 have problems with eye misalignment, a problem that is not self-correcting.
Vision testing of infants is carried out by means of a preferential looking test in which a picture containing an object made up of black and white stripes and another image that is solid gray are shown to an infant. As the striped pattern is gradually made narrower, the baby’s tendency to favor one picture or the other is observed until a preference is no longer shown for either the solid object or the striped object.
Many pediatricians recommend that parents take photographs of children under the age of 6 without the red-eye correcting function to see that the child’s eyes reflect light equally. Dilated eye exams are carried out in some cases in babies younger than 2 months to check for any serious refractive problems. Another relatively common eye care problem in children is tear duct obstruction; congenital in approximately 12% of children, this condition is self-correcting in the majority of cases. Amblyopia or “lazy eye” is reduced vision in one eye that results from the brain’s inability to process visual information from one of the eyes. Strabismus and other visual anomalies that can give rise to amblyopia can be detected by means of any of the baby eye examinations described above.
