Age-related vision loss is one of the most common forms of vision loss in people around the world. It gets worse over time, and can even lead to total blindness, which is debilitating.

A new study published in the journal Stem Cell Reports, however, offers hope of a cure. In fact, for one lucky monkey, the cure is already here.

The study was done by a team at the Kobe City Eye Hospital in Japan and found that the doctors involved were able to patch a hole in the retina of the monkey using stem cells. Once healed, the monkey’s vision was restored.

Age-related vision loss is often caused by the vitreous shrinking from the retina, which can cause a tear in the macula. Since the macula is right at the center of the retina, it is responsible for central vision as well as processing light.

Current treatments for this are not always effective and can cause the patient to lose their peripheral vision in order to improve their central vision. While this is an improvement, it is far from ideal.

By implanting stem cells, the researchers are able to patch the macular hole without taking cells from other parts of the eye, which is far preferable.

The patch used for this study was made using a sheet of retinal cell precursors from a human embryo, which is a controversial practice. Those cells were then taken and transplanted into the macular hole of the snow monkey who had lost much of its vision.

Six months later, when the monkey’s eyesight was tested, it showed significant improvement.

After analyzing the eye further, the scientists found that the monkey’s retina was able to grow new visual cells. They cannot tell, however, whether the visual cells grew out of the stem cells, or if the stem cells simply trigger a natural regeneration from the monkey’s original ones. Additional research will need to be done in this area.

Treating age-related vision loss is a game changer.

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