World-first project shows great promise to treat low eye pressure

Hypotony is characterised by abnormally low eye pressure, which alters the eye’s normal shape and internal structure. Over time, this can lead to progressive and permanent vision loss, often taking several years to result in blindness. Hypotony may develop as a result of underlying eye conditions that damage the part of the eye responsible for producing the fluid that maintains normal eye pressure.

Until now, the standard treatment for eyes losing vision from low pressure has been to fill them with silicone oil. This has many benefits but is not ideal as it can be toxic to eye structures over long periods of time and is difficult to see through.

The data published today in the British Journal of Ophthalmology indicates that ocular injections containing HPMC (hydroxypropyl methylcellulose) – a low-cost gel used in most eye surgery - can be safely used to increase the volume of eyes with hypotony, increasing both their size and pressure.

image of a doctor doing an eye check up on a patient

Remarkably, in addition to restoring the eye’s anatomy, patients also regained sight. Seven of the eight patients who received the treatment experienced improvements in vision, eye pressure and length restoration after a twelve-month course of treatment. These all came from the world’s first dedicated hypotony clinic, enabled by funding from Moorfields Eye Charity.

Moorfields consultant ophthalmologist Harry Petrushkin, lead author of the study, said: “We are excited that this simple treatment has proved so effective for patients with this rare condition. This is the start of a process of understanding more about the balance of fluid inside the eye, leading to improved care for our patients.”

Co-author Professor Gus Gazzard (UCL Institute of Ophthalmology and Moorfields Eye Hospital) commented: “This is a truly transformative new therapy that brings hope to patients otherwise without options, for what was previously an untreatable blinding and disfiguring condition. This robust proof of principle study has already exceeded my hopes of what sight recovery might be achievable.

“I hope that we shall be able to make it more widely available to more patients very soon, but of course these are early steps, and more hard work will be needed, not least to raise the funds needed to optimise this treatment.”

Nicki’s story

Nicki’s sight issues began shortly after the birth of her son, when she was diagnosed with uveitis. For several years, she lived symptom-free, until cataracts and further complications began affecting her eyes. Multiple treatments were attempted, including the use of steroids and silicone oil. While some offered temporary relief, others led to sudden drops in pressure or even complete loss of vision.

Losing vision had been frightening, but it also pushed Nicki to find out about treatment options and cutting-edge research, saying: “After I lost vision in my left eye, I thought, ‘there has to be something else we can try’. It felt good that I’d been able to advocate for myself, like they understood my concerns.”

Her turning point came when her consultants at Moorfields began exploring an alternative to silicone oil. Encouraged by her persistence, they trialled a new approach – an injection of clear gel designed to support pressure and restore function.

Reflecting on that moment, Nicki said: “We went ahead and, as the pressure improved, my vision started to come back. It was incredible!

“I want to keep my eyesight as long as I can, and this gives me that hope, as my sight has slowly returned. The progress I’ve made feels extraordinary, especially knowing that patients before me have faced irreversible sight loss.

“I remember seeing Mr Petrushkin and him saying, ‘Before this treatment, people were going blind.’ It’s incredible to know that people are regaining vision. I highly recommend this treatment. Giving people their sight back is something special.”

The Moorfields clinic integrates structured clinical assessment and collaboration with bioengineers at the UCL Department of Mechanical Engineering to understand the drivers of chronic low intraocular pressure.

This preliminary data is already informing thinking on standardised hypotony treatment nationally. It provides a foundation for future, larger-scale formal clinical trials to evaluate the potential of this highly promising approach.

Two students in UCL Medical School were also involved in the project and are co-authors on the research paper.