Author
Joanne Waeltermann, MD, Pediatric Ophthalmologist, Children's Eye Care, LLC, Catonsville, Maryland
Joanne Waeltermann, MD, has disclosed no relevant financial relationships.
Friday, December 1, 2023
Author
Joanne Waeltermann, MD, Pediatric Ophthalmologist, Children's Eye Care, LLC, Catonsville, Maryland
Joanne Waeltermann, MD, has disclosed no relevant financial relationships.
The Brückner Test: Optimizing Child Vision Screening
Vision screening is an everyday part of the primary care of children. Red reflex assessment, cover/uncover tests, Allen charts, tumbling E's, HOTV charts...all are familiar to those who care for children. But can we do a better job? The Brückner test takes the red reflex to the next level, and all that is required is a direct ophthalmoscope and a child who is willing to look at the light for just a few seconds. What makes it better than other common screening examinations?
How Do You Do the Brückner Test?
The examination takes 3 simple steps:
1. Dim the room lights.
2. Have the child sit at arm's length from you, preferably on the parent's lap, and look straight at you.
3. Shine the light directly at the child's eyes using the large white spot, and focus on the iris. Use the lowest light on the rheostat that will allow you to still see the red reflex.
What Does the Red Reflex Assess?
The red reflex allows assessment for media opacities, strabismus, refractive errors, and retinoblastoma.
• Judge the red reflexes:
o Quality and intensity
o Size of the pupil
o Position of the light reflex
o Quality of the corneal light reflexes
• The reflexes should be mirror images of each other.
The photograph above is of a child with a normal result on the Brückner test. Note the gradient of red with a lighter color at the top, which gets progressively darker toward the bottom of the pupil.
Refractive Errors: Hyperopia
Children with normal vision will have an even, symmetrical red reflex that is marked by equal color and brightness of the entire reflex. Refractive errors can be identified by lighter crescents either at the top or bottom of the pupil. Refractive errors can be unilateral or bilateral, so a careful comparison of the 2 eyes is essential.
In hyperopia (also called "farsightedness"), the lighter crescent is visible at the top. With increasing degrees of hyperopia, the red reflex will become dimmer. The child in the top photo has moderate hyperopia, marked by bright, lighter red crescents at the top of the pupil. In the child in the bottom photo, both eyes are extremely hyperopic, but the left reflex is brighter as opposed to dull because the eye is crossed -- a Brückner test result that indicates strabismus.
Refractive Errors: Myopia
In myopia ("nearsightedness"), the crescents flip so that the lighter area is at the bottom of the red reflex. The child in the top photo has mild myopia, identified by a lighter red crescent in the lower half of the pupil. The child in the bottom photo, while still exhibiting a lighter crescent on the bottom, has a red reflex that is a duller color, indicative of more moderate myopia.
Refractive Errors: Astigmatism
In astigmatism, the cornea assumes a football shape rather than the normal baseball shape. It will be seen as a red reflex that flattens into a straight line across the pupil rather than a crescent. The degree of visual impairment resulting from the astigmatic refractive error will depend on how great that refractive error is.
Refractive Errors: Anisometropia
Anisometropia is the result of unequal refractive errors between the 2 eyes. The red reflexes should be mirror images of each other. As can be seen in the images of both of these children, the color of the red reflexes and the size, position, and color of the crescents are clearly different in each eye. The degree of inequality may create amblyopia in the eye with the more extreme error.
Media Opacities: Cataracts
Both of these children have cataracts. The top image is of a child with a congenital cataract that needs to be removed by age 8-10 weeks. The child in the bottom image exhibits a posterior subcapsular cataract that is acquired. These types of cataracts can form as a result of steroid use, trauma, or inflammation.
Retinoblastoma
Most clinicians fear missing the child with a retinoblastoma. The classic finding is a loss of the red reflex and development of leukocoria, or "white reflex," as seen in the child in the top photo. The child in the bottom photo has a coloboma of the retina, a result of the choroid fissure not closing during fetal eye development.
Esotropia
Esotropia is the result of an inward turning of the eye. The Hirschberg test, which is the classic test for detection of eye misalignment, assesses the position of the corneal light reflex -- that white dot on the cornea that reflects the pinpoint light source. Children with esotropia will have asymmetry of the corneal light reflex, and the red reflex will be brighter on the eye that goes inward. These changes can be seen in the left eye of this child with esotropia.
Resources
The American Academy of Pediatrics' policy statement Eye Examination in Infants, Children, and Young Adults by Pediatricians is available online. See Red cards are available for purchase.
Author
Joanne Waeltermann, MD, Pediatric Ophthalmologist, Children's Eye Care, LLC, Catonsville, Maryland
Joanne Waeltermann, MD, has disclosed no relevant financial relationships.
