The importance of preschool vision care cannot be overstated, according to Dr. Janet Leasher, O.D., M.P.H., director of optometry community outreach and assistant professor of optometry in the Health Professions Division of Nova Southeastern University in Fort Lauderdale, Florida.
"Healthy vision is especially critical for our children to establish a strong foundation for learning. Optometrists believe that over 80 percent of the information received by our brain comes in through our eyes. Therefore, if a child is not seeing properly, the likelihood that the child will have developmental problems, learning disabilities and potentially irreparable damage to the visual systems can increase,” she says.
Dr. Leasher also notes that Prevent Blindness America estimates vision problems may affect one in 20 preschoolers. “Unfortunately, young children do not know that they are not seeing properly, and so they cannot tell their parents," she says.
Screening vs. Exams
Dr. Leasher explains that vision screenings and visual examinations are different. While vision screenings are intended to help identify children with eye or vision problems that threaten sight or impair their ability to develop and learn normally, full vision examinations provide a thorough eye-health evaluation.
“Screenings may be performed by pediatricians or family practice doctors and at schools. Parents and teachers may mistakenly assume that simple vision screenings are comprehensive eye exams, providing a false sense of security that their children are receiving all the vision care that they need,” she says.
Often simple screenings only measure visual acuity, or eyesight clarity. “A measure of 20/20 signifies that a child can see a certain size letter at a distance of 20 feet. Good vision is more than 20/20," she emphasizes.
With comprehensive vision examinations, visual acuity at all distances, focusing skills, eye movement and alignment, eye teaming, and color vision is measured and a thorough eye health evaluation is done with the pupils dilated.
"If a spectacle correction is prescribed by an ophthalmologist or optometrist for your child, qualified eye-care professionals would always recommend polycarbonate lenses (for lightness on small noses, shatter resistance and durability) with a scratch resistant finish and ultraviolet protection," Dr. Leasher says.
“Any child who is having developmental signs of decreased vision should see their pediatrician and perhaps have an eye exam to see if an ocular problem is the issue,” says David B. Granet, MD, director, Division of Pediatric Ophthalmology & Ocular Motility, University of California, San Diego.
“The pediatrician may then refer the patient to a pediatric ophthalmologist or an optometrist depending on the diagnosis. Pediatric ophthalmologists can use special drops to make an independent assessment of a child’s need for glasses at any age,” explains Dr. Granet.
Eye conditions such as nearsightedness (or myopia), farsightedness (hyperopia), amblyopia or strabismus may be discussed.
Nearsightedness occurs when objects that are close appear clear while objects that are far away, are not. “Glasses are not always prescribed for young children with myopia,” notes Dr. Granet.
With farsightedness, vision is better at a distance than near. Large amounts of farsightedness can result in eye strain, which can lead to crossing of the eyes. “Glasses are often prescribed to help a far-sighted child who is struggling to see better,” says Dr. Granet.
With astigmatism the eye is not completely round and this causes a distortion of the optical image coming into the eye. Prescription glasses can balances out the curvature.
Any misalignment of the eyes is known as strabismus. Crossed eyes, known technically as esotropia, happens when either eye may look straight ahead and the other eye will be turned inward toward the nose.
If a child’s eye is consistently crossed after four to six months of age) an eye specialist should be consulted because if the condition is not properly treated, permanent loss of vision can result.
"If a specialist determines that glasses are not indicated, there is a high likelihood that surgery will be needed to align the muscles,” says Dr. Granet.
If a child develops crossing of the eyes between age two and five, glasses are usually needed. Amblyopia (“lazy eye”) results in poor vision without any obvious injury or disease to the eyeball. Glasses are prescribed if needed. In other cases, one eye needs to be forced to see better with a patch or other method.