Multifocal Contacts in Myopia: Choroidal Changes and Clinical Implications

If it seems like more kids are wearing glasses these days, it’s not just your imagination. Global studies now indicate that roughly 35 percent of children are affected by myopia, or nearsightedness—a figure projected to climb to nearly 40 percent by 2050. That would mean over 740 million children needing corrective lenses just to see the board at school or read distant signs.

This rising tide of childhood myopia has inspired researchers like David Berntsen, Golden-Golden Professor of Optometry and chair of Clinical Sciences at the University of Houston College of Optometry, to look for effective ways to curb the problem. In collaboration with Ohio State University and backed by funding from the National Eye Institute, Berntsen and colleagues have not only identified promising interventions but are now uncovering the biological mechanisms behind them.

Berntsen leads the landmark BLINK (Bifocal Lenses In Nearsighted Kids) and BLINK2 studies, which have shown that having children with myopia wear high-add power multifocal contact lenses significantly slows the progression of their condition. Unlike standard lenses that correct vision without influencing eye growth, these specialized contacts appear to do more than sharpen sight—they help address the underlying reason children become nearsighted in the first place.

Myopia primarily develops because the eyeball grows too long from front to back, causing light entering the eye to focus in front of the retina rather than directly on it. This elongation results in blurry distance vision and sets the stage for potential future complications, such as retinal detachment or macular degeneration, especially in cases of high myopia. That’s why slowing this growth is so critical.

In their latest work, published in Investigative Ophthalmology and Visual Science, Berntsen and his team zeroed in on a part of the eye called the choroid—a layer rich with blood vessels that nourish the retina. They found that the choroid actually thickens slightly in children wearing high-add multifocal contact lenses. This thickening was associated with slower eye growth, offering important clues about how these lenses exert their protective effect.

“We evaluated changes in subfoveal choroidal thickness and area in children wearing soft multifocal contact lenses for myopia control,” Berntsen explains. “After initiating contact lens wear, subfoveal choroidal thickness and area increased in the group wearing high-add multifocal lenses compared to those in standard single vision lenses, a difference that was maintained throughout the three-year study.”

Even more compelling, the team found that choroidal changes happened early. Within just two weeks of starting to wear the multifocal lenses, children showed increases in choroidal thickness and area—and those early changes predicted how much slower their eyes would grow over the next three years. In simple terms, the sooner and more robust the choroidal response, the better the long-term control of eye elongation.

The study followed 281 myopic children aged 7 to 11, randomly assigned to wear either standard single vision contact lenses or the high-add multifocal lenses. This makes BLINK the longest-running study to date examining how the choroid changes in myopic children wearing these different types of lenses.

While much of the focus on myopia management has centered on controlling vision blur, these new insights underscore the biological story unfolding beneath the surface. By identifying a likely link between choroidal thickening and slower axial eye growth, Berntsen’s work is pointing scientists and clinicians toward a deeper understanding of how to intervene earlier and more effectively.

With myopia rates continuing to climb worldwide, studies like BLINK offer a hopeful path forward—not just to help children see more clearly today, but to protect their vision health for a lifetime.