A Cardiff woman has been able to see out of her right eye for the first time in 16 years after being fitted with a 'bionic eye' implant.
49-year-old Rhian Lewis has had the condition retinitis pigmentosa, which causes deterioration of the light-detecting cells in the retina, since she was five.
The condition has caused her to go completely blind in her right eye and almost completely blind in her left eye.
But in June surgeons at Oxford Eye Hospital implanted a small light-sensitive microchip at the back of Rhian's right eye to help restore her sight.
See also: 11 best Android phones
Since the operation, Rhian has been undergoing follow-up testing and was recently able to use her right eye to tell the time.
"That felt like Christmas Day," said the mother of two upon being able to read the time.
“On that afternoon they said they were going to switch the device on. They sort of put the magnet to the little receiver there on my head, and switched the receiver on.
"They said I might not get any sensation and then all of a sudden within seconds there was this flashing in my eye, which has seen nothing for over 16 years, so it was like, oh my God, wow.”
The implant was made by German firm Retina Implant AH, and is a 3mm sq array of about 1,500 light sensors.
The device sends pulsed electrical signals to nerve cells and is connected to a small computer, which is implanted behind her ear and powered by a magnetic coil.
From the outside this looks similar to a hearing aid.
See also: CES 2016
At first, patients see flashes of light but as weeks pass the brain learns to interpret the flashes as meaningful shapes and objects.
The images can be black and white and grainy but are a vast improvement for those who were previously blind or partially-sighted.
Because Rhian still had an intact optic nerve and all the brain wiring needed for vision, she was able to have the retinal implant, a substitute for the degraded photoreceptors, fitted.
The latest version of the chip only has 1,600 pixels (the previous chip had 1,500 pixels) but the image is refreshed regularly as the eye moves.
Although this is less than 1% of one megapixel, which is not much compared to a standard phone camera, the chip has the advantage of being connected to the human brain, which has over 100 billion neurons of processing power.
Rhian is the first patient outside Germany to be fitted with the second generation of the retinal implant, which has been tested at Oxford as a retinitis pigmentosa treatement since 2012.
Using dials on a handheld wireless power supply she can adjust the sensitivity, contrast and frequency to get the best possible signal for different conditions.
The implant operation was part of an ongoing NHS-funded trial at Oxford’s John Radcliffe Hospital.
The moment Rhian realised she had correctly told the time is captured on BBC’s “Trust Me I’m A Doctor”, to be broadcast on Wednesday night.