Case study: Smart glasses for vision loss
The effect of sight loss on quality of life
In the UK, there are almost 2 million people living with sight loss. Of these, around 360,000 are registered as blind or partially sighted. Blindness leads to a loss of quality of life, while increasing the likelihood of accidents and agoraphobia. Individuals with sight loss are highly likely to be unemployed, leading to follow on decreases in quality of life.
Age-related macular degeneration (AMD) is the biggest cause of sight loss in the UK, affecting over 600,000 people. AMD is a progressive condition that leads to loss of central vision. Central vision is responsible for most of the active functions that someone uses. Reading, driving, recognising colours and shapes, and general focus-based detail-oriented sight tasks are fulfilled by the use of central vision. Having AMD results in difficulties fulfilling these everyday tasks.
Sight loss and blindness in the adult population places a large economic cost on the UK, estimated to total £28.1 billion in 2013. Direct healthcare system costs are estimated to amount to £2.99 billion, and AMD accounts for 34% of the health system costs.
With funding from the NIHR Invention for Innovation (i4i) programme, a team of researchers from University of Oxford have built a portable augmented vision system to boost functional sight for people who are blind or partially sighted.
Due to the fact that the majority of visually impaired people have some residual vision, the researchers developed ‘smart glasses’ that capture video and images of the nearby environment and present them on the inside of small see-through displays.
The onboard computer that processes the video allows the user to customise the display to suit their eye condition and the current scenarios. Image enhancements can include changing the size of the image (to expand the patients field of view) or magnifying distant objects.
The glasses can detect and enhance edges, contrast and colour to help bring out the details of text, faces and other obstacles. The glasses also maintain the same level of lighting, which assist the wearer when going from bright to dark environments. This change in environment can often render a partially sighted patient totally blind for many minutes while their eyes adapt.
Dr Stephen Hicks, the lead Principal Investigator, said:
“We have put effort into improving the look and feel of the glasses in order to not make the wearer feel self-conscious.”
There is also an intuitive hand-held controller which allows the person to quickly and naturally change the behaviour of the glasses to suit the dynamics of the real world.
Making a difference
In a small scale cohort study led by the researchers, the smart glasses were found to improve facial recognition for people with AMD by 30%. A negligible improvement was found in people with Stargardt‘s disease, an inherited form of macular degeneration.
James has a condition called retinitis pigmentosa, whereby he struggles with low light situations and lack of confidence when travelling from place to place. He said upon using the smart glasses that:
“I’m using them all of the time, especially outside of the house - when I am eating out, getting on the right bus or train and even admiring the views of the Cotswolds.”
The researchers have completed two trials of the smart glasses with 100 people experiencing central vision loss and AMD. The researchers found that reading (speed and accuracy) was improved in over 80% of the cases. A further result showed that approximately 75% of patients could see and describe objects better with the smart glasses than their regular vision.
Another patient, Bruce, who has Ushers syndrome, said:
“They are absolutely brilliant when going into a low lit environment, like a pub or my friend’s house where they just have a lamp or candles on. Having the outline is great.”
The glasses have been awarded a CE mark and approved by the FDA. In 2016 the researchers set up spin out company OXSIGHT, in which NIHR has a small equity stake.
In May 2020, OXSIGHT finished work on their new headset called ONYX. ONYX is designed for people with central vision loss conditions such as AMD and it is smaller, lighter, easier to use and cheaper than other devices on the market.
Over six months, OXSIGHT tested ONYX with 125 people who were either legally blind or partially sighted. Most of the trialists had some form of central vision loss. Approximately 80% of people who tried ONYX were able to read text better. In most cases, participants could read 3-4 lines higher on a letter chart, and approximately 20% of people who could not read at all, could now ready comfortably. In addition, trialists improved face perception and object descriptions.
ONYX was very well received and many people on the trial were keen to take the prototype home with them. They said that they would like to use ONYX for watching TV, shopping and doing crossword puzzles.
OXSIGHT is preparing to make the necessary changes to ONYX and prepare it for manufacture. OXSIGHT is securing new investment to manufacture ONYX. They hope to have the product ready for purchase by Summer 2021, which will be good news for people suffering from AMD and other forms of sight loss.
Funding awards from NIHR Invention for Innovation (i4i) programme funding stream:
- A low-cost non-invasive visual aid for severely sight impaired individuals
- A wearable smart visual aid for central vision loss
Read more making a difference stories.