New vision test could help diagnose vision loss in toddlers

Friday, January 24, 2020

Dr. Susan LeatA simple new test being developed by University of Waterloo researchers could help detect vision impairment in very young children, allowing them to receive sight-saving treatment as soon as possible.

Existing eye tests rely on children’s ability to identify letters or match shapes, making it difficult to diagnose vision loss in children under the age of three.

“Tests are available which rely on the direction of a baby’s gaze to determine whether or not they can see a particular visual stimulus; however, these ‘preferential looking’ tests use specially calibrated printed images that are expensive to produce. These tests are also not as good at detecting vision disorders as those that ask older children to match shapes,” said Dr. Susan Leat, a professor at the School of Optometry & Vision Science and lead author of the study.

The research team proposes using a computer display with a variety of shapes. But instead of requiring children to match a shape, they’ll be asked to point to a specific shape. When they choose correctly, an animation will play.

“Our earlier research with adults showed that this method of measuring visual acuity gives the same results as when you ask the person to read the letters on the letter chart aloud,” said Dr. Leat.

Besides being an effective measure of visual acuity, the new test offers other benefits as well. Because it uses simple shapes, not letters, it can be used in any country and printed versions will be easier and more economical to print than the more complex preferential looking tests.

The project recently received a $171,300 grant from Fighting Blindness Canada (FBC), the country’s largest private charitable funder of vision research.

“We believe this project could have an immediate impact,” said Dr. Larissa Moniz, FBC’s Director of Research and Mission Programs, of the funding decision.

“It will allow earlier diagnosis of vision problems and hopefully lead to better outcomes. It has the potential to become part of clinical care in the near future.”