Siloton develops specialized OCT for pediatric eye tests

British photonics start-up Siloton has announced that a collaboration with UCL Great Ormond Street Institute of Child Health will develop a novel OCT platform designed specifically to monitor children's eyes.

The modified OCT system will make use of Siloton's photonic chip technology, intended to allow platforms to be considerably more compact and robust than a traditional instrument.

Siloton was founded in 2020 to leverage integrated photonics into the healthcare sector, with ophthalmology its first target.

The company took its first image of a human retina in 2024, having by then been awarded three patents outlining its research. One relates to an on-chip component to compensate for natural variation in the distance of patient retinas from the chip; a second to the internal structure of the optics used to ensure optimal chip performance.

A third patent covers an optical arrangement for imaging both eyes without doubling the number of components or requiring patient intervention.

Siloton's first-generation Akepa device compresses "a tabletop-worth of heavy, expensive, and fragile components onto a single chip smaller than a £1 coin." It has been designed to work as part of a binocular-style system that makes the diagnosis and monitoring of a range of treatable retinal diseases more affordable and accessible.

A first cohort of adult patients successfully trialled the technology last year, and the new project will see the OCT system adapted physically and interactively so it can be used by children. The device's lenses will be tuned to focus on the correct place within a child's eyes, while the casing will be better shaped to their faces to prevent light from affecting the imaging process.

"Until now our patient focus groups have largely involved adults, because age-related macular degeneration – the leading cause of sight loss in the UK – predominantly affects older people," said Siloton cofounder and CEO Alasdair Price. "But the fundamental principles of imaging the eye are the same, and with the right adaptations Akepa can work just as effectively for children."

Second-generation photonic chip for spaceflight

Siloton has also announced a collaboration with the European Space Agency to build its miniaturised eye-scanning chip into a platform for monitoring the eyesight of astronauts during lunar and Mars exploration missions.

The goal is to tackle Spaceflight Associated Neuro-ocular Syndrome, or SANS, a set of ophthalmic conditions observed predominantly after long-duration space flight characterised by optic disc edema, posterior globe flattening, optic nerve sheath distension and other deteriorations.

SANS affects 70 per cent of astronauts aboard the International Space Station above Earth, noted Siloton, and can cause lasting damage to vision. At present astronauts are monitored by an OCT platform onboard the ISS, but even though modified for this purpose the platform still weighs 30 kilograms.

Siloton will incorporate its integrated photonic circuit into an OCT system the size of binoculars and weighing less than two kilograms.

"Astronauts living on the lunar surface for long periods or on a journey to Mars will need their eyes to be monitored as carefully as the spacecraft's instruments, and our system does that without a doctor on board," said Siloton CTO Euan Allen.

"For our contract with the European Space Agency we will be using our second-generation chip, BlueJay, which advances image quality over the previous generation. What we can now achieve with miniaturised OCT will help spaceflight, but equally patients with eye conditions here on Earth."