SCIENTISTS have developed a 'pellet' implant that's injected into the eye to prevent cataracts forming - and might even reverse the growth of existing cataracts without surgery.
The implant, thought to work by lowering calcium levels in the eye, is being tested in the first clinical trial.
About 350,000 cataract operations are performed in the UK each year, and it's estimated one in three people aged 65 has a cataract in one or both eyes.
Cataracts are cloudy patches on the lens in the eye, which cause blurred vision and eventual blindness if left untreated.
Most cataracts develop as a result of age-related changes in the lens, specifically oxidative stress. This occurs when there is an imbalance between free radicals (unstable atoms that damage cells) and antioxidants (which keep free radicals in check).
Cells in the body produce both, though factors such as smoking, drinking too much alcohol and exposure to chemicals can speed up production of free radicals.
As we age, fewer antioxidants are produced, resulting in oxidative stress, which leads to tissue damage (with proteins and fibres in the lens beginning to break down), and a build-up of calcium in the lens.
Cataracts can also be linked to conditions such as diabetes, and to medications, including long-term use of steroids.
The cloudy lens can be replaced in a 30-minute operation under local anaesthetic - the surgeon makes a tiny cut in the eye to remove the lens and replace it with a plastic one.
The implant treatment, NPI-002, from US-based Nacuity Pharmaceuticals, could mean such surgery is no longer needed.
The implant is loaded with antioxidants and injected into the vitreous - the gel-like fluid between the lens and retina (the light-sensitive area in the eye).
The implant slowly releases its contents into the vitreous, which carries them to the lens where it acts on the cataract. The solution includes N-acetylcysteine amide (NACA), an effective antioxidant.
An animal study by ophthalmologists at Washington University in the US and other centres, reported in the journal BMC Ophthalmology in 2018, showed the implant prevented and reduced the severity of cataracts.
It also led to an increase in protective antioxidants and reduced calcium levels to 2.5 times lower than in a control group.
The first human trial, in the US, will start soon and will involve 30 patients aged 65 and over with cataracts.
Gwyn Williams, a consultant ophthalmologist at Singleton Hospital in Swansea, said: "It is a very interesting idea and I look forward to seeing the results.
"Cataracts are multifactorial and I am sceptical whether this one approach will be effective by itself, though this remains to be seen."
© Daily Mail
