Thousands of people affected by sight loss could benefit from a biodegradable implant that slowly releases a drug into the eye, it has been announced.
More than 200,000 people in the UK suffer from retinal vein occlusion (RVO), which can lead to sudden loss of sight.
The retinal veins, which drain blood away from the back of the eye from the retinal cells, become blocked as a result of RVO.
This can cause a build up of blood and create swelling that damages the retina cells and puts eyesight at risk.
People can experience sudden sight loss, blurred vision, straight lines appearing wavy, or the appearance of a black spot in their central vision.
Now, a new implant called Ozurdex has been approved for use in the UK as the only treatment for RVO.
The Royal National Institute of Blind People (RNIB) said the implant was an "exciting new development", although it has yet to be appraised by the National Institute for Health and Clinical Excellence (NICE) for widespread use on the NHS.
The implant, which is injected directly into the back of the eye near the retina, has been shown to improve or help prevent the worsening of sight loss.
In the first two months, a high dose of the anti-inflammatory medicine dexamethasone is released, which reduces swelling.
A lower dose of dexamethasone is then released over the next four months, stopping the swelling from getting worse.
Once in the eye, Ozurdex biodegrades into water and carbon dioxide over the six months, meaning it does not have to be surgically removed.
A clinical trial on more than 1,000 patients found that one implant significantly improved vision by up to three lines (or 15 letters) on an eye chart.
It was shown to improve or stabilise vision in more than 80% of patients.