2-3
The young child's retina continues to develop rapidly until about the age of _____ to ____ years
7 or 8
After the rapid development stage, peripheral development slows until its completion at age ____ or ____
To catch problems before development is complete
The aim of screening in visual development
Refraction
Focusing light accurately on the retina
Refractive error
Due to the shape of the eye. The most common types of this error are myopia, hyperopia, and astigmatism
Myopia
nearsightedness; occurs when the image is focused in front of the retina
Hyperopia
farsightedness; occurs when the image is focused behind the retina
Astigmatism
defective curvature of the cornea or lens of the eye which causes light rays entering the eye to focus at two different points; vision is blurred and distorted at both distance and near
50%; 5yo
Approximately _____% of very young children have astigmatism, which decreases to about 10% by the age of ____
TRUE
T/F - Nystagmus may dampen on convergence
Head tilt
In cases of nystagmus, there may be regions of "best gaze" that may result in _____ _____
Infantile, Spasmus nutans, acquired
Types of nystagmus
Infantile nystagmus
Most often develops by 2 to 3 months of age. The eyes tend to move in a horizontal fashion. It is often associated with other conditions, such as albinism, congenital absence of the iris (the colored part of the eye), underdeveloped optic nerves and conge
Spasmus nutans
Usually occurs between 6 months and 3 years of age and improves on its own between 2 and 8 years of age. Children with this form of nystagmus often nod and tilt their heads. Their eyes may move in any direction. This type of nystagmus usually does not req
Acquired nystagmus
This type of nystagmus develops later in childhood or adulthood. The cause is often unknown, but it may be due to central nervous system and metabolic disorders or alcohol and drug toxicity.
Birth - 8 weeks
During this stage of visual development, the baby has stable eye contact for visual fixation. The baby prefers patterns and faces and has sight 8-12 inches from his/her face
1 month
During this stage of visual development, the baby follows objects about 90 degrees, has 20/400-20/800 acuity, and stares at light
3-4 months
During this stage of visual development, the baby has developed the social smile, is aware of hands, bats at objects with arms, watches finger movements, and any signs of strabismus should be greatly diminished or non-existent
5 months
During this stage of visual development, the baby watches the hand movements of others and has developed good color vision
6 months
During this stage of visual development, the baby is beginning the gross grasp of objects and is developing depth perception
7-11 months
During this stage of visual development, the baby stares at smaller objects, has approximately 20/50 acuity, and picks up small objects
Teller Acuity Cards
preferential viewing for infants; vision is determined by the smallest stripes that the child looks towards
visual evoked potential (VEP)
An electrical response to visual stimulation recorded by the placement of disk electrodes on the back of the head. This potential reflects the activity of a large population of neurons in the visual cortex; strength of the signal and speed of the signal i