The mask, known as a continuous positive airway pressure (CPAP) device, is worn at night over the nose and mouth.
It is widely used by people with obstructive sleep apnoea — where the soft tissue of the throat collapses, partially blocking the airway.
Sleep apnoea is a common cause of snoring, and the mask works by forcing a stream of compressed air into the airway which keeps it open.
Scientists have now discovered that this technique may also hold benefits for patients with diabetic retinopathy.
This is where high blood sugar levels damage the light-sensitive cells at the back of the eye, in an area called the retina.
These cells need a constant supply of blood, but a chronically high blood sugar level can leave blood vessels blocked or leaking, leading to blindness if not treated properly.
Forty per cent of people with type 1 diabetes and 20 per cent of those with type 2 diabetes have some degree of retinopathy, with up to 800,000 Britons affected.
A small trial has shown that the night-time mask improves eyesight in patients with diabetic retinopathy after just six months of use.
In the study — at the Churchill Hospital in Oxford — 35 patients with diabetic retinopathy were given the treatment, and their vision improved significantly.
The devices were used every night for varying time periods, with the best results seen in those who wore it for more than two-and-a-half hours.
It’s thought the mask boosts oxygen levels in the blood which, in turn, helps reduce blood pressure.
High blood pressure is known to accelerate the damage to the delicate blood vessels in the eye.
Diabetics are more likely to suffer from sleep apnoea compared to healthy people
Interestingly, research has also shown that diabetics are more likely to suffer from sleep apnoea compared to healthy people.
It’s thought this might partly explain the sight problems linked to diabetes, raising the suggestion that diabetics who regularly snore may be at increased risk of eye damage.
Now, researchers from the Royal Victoria Infirmary in Newcastle plan a larger one-year trial on 150 patients with diabetes.
Half of them will use the mask every night, while the remainder will continue with their usual medication.
They will also have regular checks of their visual acuity — clarity or clearness of vision — as well as retina scans and blood tests to check oxygen levels.
Commenting on the research, Professor Glen Jeffery of the Institute of Ophthalmology, says: ‘This is a potentially important finding.
‘Although, initially, the results seems slightly surprising, the scientific rationale behind it makes sense.
‘The study targets problems in the eye, but in the long run it would be interesting to see if it impacts on other problems that diabetics have.
‘There are potentially big advantages if this is effective.
'It is not centred around expensive drug therapy and, hence, it may reduce the very heavy economic and social burden of diabetes.
‘Plus it may also allow the patient’s partner to get a better night’s sleep.’
Scientists have found that cinnamon may help reduce the symptoms of type 2 diabetes.
New research suggests the spice mimics the effects of insulin and triggers tissues in the body to absorb glucose.
Good glycaemic control — control of blood-sugar levels — is an important goal of diabetes care.
Researchers from Imperial College London analysed data from studies involving a total of 435 patients. Cinnamon had been used in a range of doses, from 1-6g a day.
‘Cinnamon may be a viable addition to conventional diabetes management for patients with poorly controlled blood sugar,’ say the team, writing in the journal Clinical Nutrition.
They say the effects of the spice were seen over a relatively short space of time — in some cases as little as four months.
‘Use of cinnamon showed a beneficial effect on glycaemic control and the short-term effects of the use of cinnamon looks promising.’
Other studies suggest that the herbs marjoram and sage may also help reduce the damage caused by type 2 diabetes, due to their high content of antioxidants which help lower inflammation.