By Lily Clarke
Often overlooked is the fact that diabetes sufferers may go blind as a result of their disease. Current treatment for early stage eye damage due to diabetes relies purely on the patient controlling their diabetes more. Invasive and uncomfortable procedures such as laser surgery or injection therapy can help those with a later stage of eye damage. However, it may be possible that a non-invasive treatment that can prevent and reverse this eye damage is just around the corner.
Diabetes is a life-long condition which results in the body being unable to control blood sugar levels, leading to these levels becoming too high or too low. It is estimated that there are around 3.9 million cases of diabetes in the UK alone, 90% of which are Type 2 diabetes. Those with diabetes either do not produce a hormone called insulin, which regulates blood sugar, or their insulin does not work properly. There is currently no cure for diabetes, but plenty of work is being done in the medical engineering field at the moment to make life easier for those suffering from diabetes.
One side effect of high blood sugar is diabetic retinopathy – in other words, damage to the retinas due to high blood sugar. At Noctura, scientists have developed a sleep mask which is claimed to prevent and even reverse the effects of diabetic retinopathy.
The Noctura 400 sleep mask is designed to try and combat diabetic retinopathy by stopping the eyes from dark adapting at night, as this is primarily when damage to the retina occurs. The retina is a collection of cells at the back of the eye, where light from incoming images is converted into electrical signals that the brain can understand. There are two types of cell in the retina, known as rods and cones. The cones work best during the day, but it is the rods that take over at night as they are more sensitive.
The retina works by receiving a constant blood supply from tiny blood vessels. At night, the rods ‘dark adapt’ – this requires more oxygen to be delivered by these blood vessels than during the day, and happens even when we sleep. In diabetic patients, where circulation is already compromised, the oxygen levels are not high enough to deal with the demand, and so the retina is damaged by oxygen starvation known as hypoxia. This causes a vicious cycle where the body tries to correct this by forming new blood vessels which are weak and leak fluid, damaging the eye further.
When this happens, the retina no longer works how it is supposed to, and this can eventually lead to blindness if left untreated. This is known as diabetic retinopathy, or diabetic eye disease.
In order to combat this damage, the Noctura 400 sleep mask is designed to stop the rods in the retina from ‘dark adapting’ at night, so that this heightened period of damage is reduced. The mask is made up of a cushioned eye mask, with a slot for a plastic ‘pod’ which emits a low level of light. The mask is worn at night during the patient’s normal sleeping hours. The pod emits a specially chosen light frequency through the patient’s eyelids while they sleep, designed not interrupt the wearer’s normal sleep pattern by the light frequency only being absorbed by the rods. The Troxler effect allows the eyes to adjust to the light quickly, so it is completely unnoticeable while sleeping.
The light emitted from the mask is bright enough that the rods in the retina do not try to adapt to low lighting levels and so the oxygen flow to the retina remains at low daytime levels. This effectively prevents the most damaging cycle leading to diabetic retinopathy.
Clinical trials are currently being undertaken, but a recent pilot trial showed very positive results in diabetic patients already suffering from diabetic retinopathy.