Age-related macular degeneration (AMD) is one of the leading causes of vision loss among older adults. It affects the retina, the light-sensitive layer at the back of the eye that helps us see.
When AMD progresses, it damages the central part of the retina called the macula, making it hard to see fine details or recognize faces. Roughly one in three people over the age of 80 develops AMD.
In the United States alone, around 20 million adults over 40 live with this condition. Most of them have the “dry” form, which develops slowly and currently has no effective treatment.
But now, researchers at Aalto University in Finland have found a promising new approach that could slow or even stop the early stages of dry AMD. The method involves using gentle heat to stimulate the eye’s natural repair systems and protect the cells of the retina.
Professor Ari Koskelainen, who led the study, explained that as we age, the protective mechanisms inside the eye become weaker, leaving it vulnerable to oxidative stress—a buildup of damaging molecules called free radicals.
These radicals attack proteins, causing them to lose their normal shape and clump together. Over time, fatty deposits known as drusen form under the retina, which is a key sign of dry AMD.
The idea behind the new treatment is simple but clever: by slightly warming the eye tissue, scientists can activate the body’s own defense and cleaning systems. However, the technique is technically challenging because the temperature at the back of the eye is difficult to measure. If the tissue gets hotter than 45 degrees Celsius, it can be damaged.
To overcome this, the Aalto research team created a method that allows real-time monitoring of temperature while heating the area with near-infrared light. This makes it possible to apply the right amount of heat safely and precisely.
When heat is applied to cells, it can trigger two natural repair systems. The first involves heat shock proteins, special molecules that help fix damaged or misfolded proteins by reshaping them. If repair isn’t possible, these proteins are broken down into amino acids and recycled.
The second mechanism, known as autophagy, acts like a cellular waste removal system. It was first described by Nobel Prize winner Yoshinori Ohsumi in 2016. During autophagy, damaged or clumped proteins are wrapped inside a membrane bubble and digested by enzymes, clearing away the harmful buildup.
According to Koskelainen, the team discovered that their gentle heat treatment could trigger both of these processes—heat shock protein production and autophagy—at the same time. “This process is like waste disposal,” he said.
“We were able to show that we can activate both systems using heat shocks.” This finding suggests that controlled heat can help the eye clear away damaged material, restore protein balance, and protect against further degeneration.
The results from animal studies in mice and pigs have been highly encouraging. In these tests, the controlled heat therapy improved retinal health and prevented some of the damage linked to AMD. The research team now plans to start human clinical trials in Finland in 2026.
The first phase will focus on ensuring the safety of the laser-based treatment and determining how often patients might need it to maintain its benefits. “The treatment needs to be repetitive, since the response can already begin to decline some days after the treatment,” Koskelainen explained.
The study, published in *Nature Communications* on October 29, has already attracted attention for its potential to change how AMD is treated. The team has launched a start-up company called Maculaser to help bring the therapy from the lab to real-world clinics.
Koskelainen says that, if all goes well, the treatment could be available in hospital eye clinics within three years and later become a routine procedure offered by ophthalmologists.
In reviewing these findings, experts note that the new heat therapy stands out because it supports the eye’s natural healing processes rather than relying on drugs or surgery.
By strengthening the body’s own defenses, this technique may offer a safer, more sustainable way to slow the progression of AMD and preserve vision. If clinical trials confirm its success, it could give hope to millions of older adults facing gradual vision loss worldwide.
If you care about eye health, please read studies about how vitamin B may help fight vision loss, and MIND diet may reduce risk of vision loss disease.
For more information about eye disease, please see recent studies about how to protect your eyes from glaucoma, and results showing this eye surgery may reduce dementia risk.
The study is published in Nature Communications.
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