New Vision Test for Toddlers Developed at University of Waterloo

A groundbreaking vision test designed for toddlers has been developed at the University of Waterloo, potentially transforming how eye doctors diagnose vision problems in very young children. The new tool, known as the Waterloo Differential Acuity Test (WatDAT), aims to measure visual acuity in children as young as 18 months old. This innovative approach utilizes a simple yet effective methodology: children are shown four images, three of which are identical, and asked to identify the one that is different.

As the child successfully identifies the odd image, the task progresses to smaller images, allowing for an accurate assessment of their vision. This engaging approach is particularly important, as 14% of children within this age range may have undiagnosed vision issues, such as astigmatism, farsightedness, or amblyopia, commonly referred to as lazy eye.

Addressing a Critical Need for Early Detection

Dr. Susan Leat, a professor emeritus at the University of Waterloo, emphasized the significance of early detection in a recent interview with CTV News Kitchener. “Measuring these types of vision problems is important because if they’re not detected or treated, it can affect the child’s learning. It can also affect the child’s general development,” she stated.

Vision disorders in young children are often not easily recognizable by parents or caregivers. “Children will not complain about poor vision because they don’t know what good vision is,” Dr. Leat explained in a press release. The potential for early diagnosis could lead to more effective treatment options, significantly impacting the child’s developmental trajectory.

Traditionally, optometrists have relied on eye movement tests for infants and toddlers, which track a child’s gaze toward striped patterns. These tests provide limited information, only indicating whether a child can see a pattern rather than assessing their ability to recognize or interpret details. Older children typically undergo tests involving pictures or letters, which are not suitable for toddlers who lack the necessary vocabulary or attention span.

An Innovative Approach to Vision Testing

The WatDAT method, however, allows for a more accurate assessment by starting with larger images and gradually introducing smaller ones. “This is equivalent to the letter test that an adult would be asked to read when they’re at the optometrist,” Dr. Leat explained. The test’s reliance on visual matching rather than language makes it more accessible for toddlers.

In trials, nearly all children aged 24 months and older who met developmental milestones successfully completed the test using both eyes. The test also proved effective for children born prematurely or those with other health challenges, broadening its applicability.

Currently, optometrists in Canada, the United States, and the United Kingdom are beta-testing both printed and digital versions of the WatDAT system. In its digital format, the test includes interactive elements, such as rewarding children with a cartoon animation, like a dancing Winnie the Pooh, when they point to the correct answer. This playful engagement helps alleviate any anxiety children may feel during testing.

“WatDAT is kind of unique — there’s nothing like it,” Dr. Leat remarked, highlighting the test’s innovative nature and its ability to resonate more with children compared to traditional testing methods. With the testing phase nearing completion, researchers are optimistic about commercializing the tool for use in clinics worldwide.

“Once it’s on the market, it will be available for optometrists and ophthalmologists to purchase,” Dr. Leat added, indicating a promising future for early childhood vision screening. As the WatDAT tool moves closer to market availability, it holds the potential to revolutionize how vision issues in young children are diagnosed and treated, ultimately benefiting their development and learning.