The University of Arizona

The Tohono O'odham
Vision Screening Program

The University of Arizona



    The Tohono O’odham Vision Screening Program was a collaborative program conducted by The University of Arizona Department of Ophthalmology and Vision Science, sponsored by the Tohono O’odham Nation, and funded by the National Institutes of Health/National Eye Institute (NIH/NEI).


    The program was initiated because many Tohono O’odham adults and children have an eye problem called astigmatism.


    Astigmatism means that the front of the eye is not perfectly round. This makes it difficult for the eye to focus. People with astigmatism cannot see clearly up close or far away without eyeglasses or contact lenses.


    The program sought to learn more about astigmatism for the benefit of the Tribe and the medical community in general, while offering services that improved the visual health of Tohono O’odham children.


    What we learned


    Tohono O’odham children have a high need for eyeglasses:


    Many Tohono O’odham infants and toddlers have astigmatism. It is common for infants to have astigmatism, but it typically goes away as a child grows older. However, in many Tohono O’odham infants, the astigmatism does not go away with age.


    By the time they reach preschool, about 1 in 3 Tohono O’odham children (33%) require eyeglasses for astigmatism. This compares to about 1 in 10 children (10%) from other communities.


    By the time they reach elementary school, about half of Tohono O’odham children (50%) require eyeglasses. This compares to about 1 in 10 children (10%) from other communities.


    Astigmatism does not tend to either increase or decrease from age 3 to 18 years. A child who needs eyeglasses for astigmatism is likely to continue to need glasses.


    For children with astigmatism, wearing eyeglasses is very important:


    Eyeglasses have immediate benefits: Astigmatism causes blurred vision for things up close and far away. Eyeglasses improve vision immediately by providing focused images.


    Continued eyeglasses wear has long-term benefits: The blurriness caused by astigmatism can result in poor development of the visual part of the brain (a form of amblyopia, or “lazy eye”). When this happens, the child may not see perfectly, even when wearing eyeglasses. The treatment for this type of “lazy eye” is to wear eyeglasses. Over time, the glasses allow the visual part of the brain to receive focused images and the brain uses focused images to learn to see more clearly.


    Eyeglasses can help children perform better in school: Reading fluency and visual-motor performance in children with astigmatism improves when they wear their glasses.


    The best way to screen young children (preschool and younger) for astigmatism is to use a machine, rather than an eye chart. The machine takes a measurement without touching the eye. A vision screening machine was provided to the Tribe through the program and is used by trained non-medical personnel from the Tohono O’odham Early Childhood Programs.


    Even though astigmatism comes from the cornea (the front surface of the eye) it does not seem to be associated with other more serious corneal conditions, such as keratoconus, in Tohono O’odham children.


Joseph M. Miller, MD, MPH
Medical Director

Erin M. Harvey, PhD

The University of Arizona
Department of Ophthalmology and Vision Science
655 N. Alvernon Way, Suite 108
Tucson, AZ 85711


Funding Provided By

Sponsored By
The Tohono O’odham Nation
The University of Arizona
The National Eye Institute of the National Institutes of Health