ESA backs compact eye scanner: chip-scale eye checks edge closer

The European Space Agency has backed UK startup Siloton to build a compact retinal scanner for astronauts headed into deep space. The idea is to push chip-scale optical coherence tomography eye exams closer to something NASA could actually use on Artemis missions.

The concern here is Space-Associated Neuro-ocular Syndrome, usually shortened to SANS. Space medicine researchers have seen signs of it in 70% of astronauts on the International Space Station, and in about 15% to 20% the symptoms are serious enough to matter clinically. That can mean swelling of the optic nerve, flattening at the back of the eye, and folds in the retina that blur vision and nudge astronauts toward farsightedness. Sometimes the change is dramatic. After his 2005 ISS mission, astronaut John Phillips came back with much worse eyesight, even though it improved later.

The leading theory is that microgravity pushes fluid upward toward the head, which raises pressure around the brain and the eyes. The ISS already has a modified OCT system to keep an eye on this, but it still takes a bulky setup, and crews often need real-time guidance from specialists on the ground.

Siloton is trying to shrink those OCT-type components onto a photonic chip smaller than a coin and fit it inside a device about the size of binoculars. If that works, astronauts could scan themselves more often and with less training on Moon or Mars missions, where time delays make live support impossible. If you follow space medicine, this one’s worth watching. You can’t get it yet, and NASA’s own self-operated Mini OCT for the ISS is also penciled in for 2027.