What the optometrist is looking for during the assessment
Babies can’t speak. How do you test their vision?
Optometrists have the clinical background and expertise necessary to provide eye and vision assessments for any non-verbal patients, including infants. The optometrist is looking for answers to the same questions you are:
- Does the patient history suggest a problem?
- Can the baby see?
- Are the eyes straight?
- Are the eyes healthy?
- Is intervention necessary?
Some eye conditions are strongly linked to family history, so the first step for the optometrist is to compile a history on the child. A comprehensive patient history for infants may include any problems you have noticed, visual and ocular history, general health history, family eye and medical history, developmental history and demographic data.
Factors placing an infant, toddler, or child at significant risk for visual impairment include:
- Prematurity, low birth weight, oxygen at birth
- Family history of eye diseases such as retinoblastoma, congenital cataracts, or metabolic or genetic disease
- Infection of mother during pregnancy (e.g., rubella, toxoplasmosis) or drug/alcohol use during pregnancy
- Sexually transmitted diseases, cytomegalovirus, or HIV
- Difficult or assisted labor, which may be associated with fetal distress or low Apgar scores
Because traditional eye chart testing requires identification of letters or symbols and demands sustained attention, this test cannot be used with infants and toddlers. Assessment of visual acuity for infants and toddlers may include tests to assess that the infant can fix his eyes on an object and follow the object, or at which objects the baby prefers to look, and at what distances.
The doctor may use lenses and light from a small hand-held instrument to assess how the eye responds to particular targets. The doctor may also repeat this test after using eye drops to enlarge the pupil and stabilize the baby’s focusing. As an alternative, some doctors use photographic testing to then analyze the pupil reflex in the photo.
The typical infant may have some degree of nearsightedness, farsightedness, and astigmatism not requiring correction. Studies show that 30 to 50 percent of infants under 12 months have significant astigmatism, which declines over the first few years of life, becoming stable between approximately 2½ to 5 years of age. Low amounts of anisometropia (where the refraction is not the same in both eyes) are common and variable in infants.
Using her hands, a light, or a toy, the optometrist catches the baby’s attention and observes how the baby follows the movements of the object.
Eye Alignment/Binocular Potential:
By covering one eye at a time, the optometrist gathers information about the eye muscles and acuity. While identifying strabismus is important in itself, the presence of strabismus may indicate any number of disease entities.
The optometrist will examine the eye’s structure as well as eyelids, tear ducts, and other parts of the eye. Pupil function will be checked, and a hand-held biomicroscope may be used for evaluation of the front of the eye. A test to assess visual field will be completed and an examination of the inner eye through a dilated pupil will be done. An ideal time for evaluation of the posterior segment is when the infant is in a calm, relaxed, condition (i.e., being bottle fed or sound asleep).
In addition to sharing her findings with you, you may request the optometrist to send summary letters to the infant’s pediatrician, family physician, or other appropriate practitioner, reporting and explaining any significant condition diagnosed in the course of the assessment.