Eyesight in Infants
Warning signs of vision problems
Newborns are complex and exciting individuals. Most parents look forward to observing their infant develop rapidly, as each new accomplishment is exhilarating. What should one expect from newborn eyes and from their eyesight? What is considered normal, and what are warning signs for parents to watch for?
Even at birth, infants can see, although dimly. They must be in the proper state of alertness, as newborns do not follow objects just after birth. Most of their time will be spent eating and sleeping, as any parent quickly learns.
The eye itself is mostly well formed at birth, but the fovea, part of the retina used for seeing fine details, is not at all completely developed. Much development will be completed by age 6 months (allowing the 6-monthold infant to see 20/20 when measured electronically), but foveal development actually continues for many years.
Most infants begin to fixate (look briefly at large objects) and readily follow them between ages two and four months. If your child is not looking at objects and following them fairly well (for at least 30 to 60 degrees or more) by age 4 months, there could be a problem. However, if your child was born prematurely, you should treat the development (more or less) as if the due date, not the actual birth date was the time of birth, for development purposes. That is not exactly correct, but closer than judging by the birth date.
The system of binocularity, working the eyes together to see one image with two different eyes, is complex. Many children do not have eyes that work together, especially in the first three to five months of life. Drifting outward of one eye at times is pretty normal, and not a real concern unless it persists after age 6 months. Turning inward is less common, but the great majority of those eyes will line up by age 6 months. If your child’s eyes are very, very crossed, that is likely to be an eye muscle problem, and your child should be checked between ages 4 and 5 months of age. But most parents should wait until age 6 months to assess whether the eyes line up and work together.
The mother noted the left eye turning outward. The left eye has a cataract and needs prompt surgery.
Watering of the eyes is quite common in early childhood. In 5 to 15 percent of newborns, the eyes will begin to water in the first six to eight weeks of life (or later) as the drainage system for tears is not yet complete. A yellow mucoid discharge may be present which should be gently wiped away. Topical antibiotic drops should be used if the yellow discharge persists or the eye itself becomes red. If the eyelid becomes extremely red and swollen, oral antibiotics will be needed. Sometimes the infant will need hospital admission and IV antibiotics Warning signs are if the child is also very sensitive to light, or if the eye enlarges or the front of the eye becomes hazy, which could indicate infantile glaucoma. But if you see yellow discharge, the problem is most likely nasolacrimal duct obstruction.
An infrequent but serious sign is the presence of a white reflex in the pupil, which could indicate retinoblastoma, a highly malignant tumor that occurs in one of 16,000 births. Digital photography often takes a picture of the optic nerve, which is normally white. Nonetheless, your child should be checked immediately if the pupil appears white by observation or photograph.
The eyes should be aligned by age six months. If not, an ophthalmologist skilled in examining young children should be seen. The majority of strabismus (ocular misalignment) does not have a serious underlying cause (retinoblastoma can present this way), but still affects vision and early exam and treatment are recommended.
Head tilts, or torticollis, may be ocular in origin, due to misalignment of the eyes. But most torticollis is neuromuscular, but an eye exam is indicated.
Unequal pupils are often noted at some point after birth. Most patients have no serious condition unless the eyelid is lower (ptosis) on the side of the smaller pupil, as an uncommon tumor called neuroblastoma can present this way. Also, a local eye problem or iris abnormality can cause unequal pupils.
The eyes should not “jump” back and forth, a condition called nystagmus. The problem can be familial, or unassociated with serious eye problems. But an eye exam is required as serious eye problems can present this way.
Drooping of one or both eyelids (ptosis) from a young age usually indicates weakness in the eyelid muscle that elevates the lids. But an older child who develops ptosis may have a serious underlying disease, such as this child whose myasthenia gravis was diagnosed in the office with an ice test.
The most common problem in children that is usually not noted by parents is amblyopia, especially the form in which one eye is out of focus and the eyes well aligned. The child can appear to see quite well, but one eye can have serious visual loss that can be treated in early childhood. Many pediatricians now utilize “photo-screening,” which can determine if one or both eyes are out of focus, in children as young as 6 months old.
And yes, some young children, even age 4 to 6 months, require glasses for vision to develop properly. Sitting close to the TV or holding objects close to the face can be a sign, but many children with normal vision engage in those behaviors. Photo-screening by your pediatrician is helpful, and prompt referral to a physician if the eyes are not aligned (which often indicates a need for glasses) will detect most of these problems.
Dr. Alan B. Richards is a pediatric ophthalmologist at Highland Clinic. Dr. Richards has special interest in the treatment of strabismus (eye muscle problems such as crossed eyes), amblyopia or lazy eye, ptosis or drooping eyelids, and nystagmus. He is accepting new patients and can be reached at 222-8402; located at 1400 East Bert Kouns Industrial Loop, Suite 103, Shreveport. Visit www.highlandclinic.com/staff/alan-richards-m-d for more information.