‘Bionic eye’ expert presents ground-breaking results in Milan
The pioneering eye surgeon behind the 'bionic eye' retinal
implant programme at Manchester Royal Eye Hospital(MREH) has joined
experts from across Europe to present his latest findings at the
12th EURETINA Congress in Milan.
Paulo Stanga, Professor of Ophthalmology & Retinal
Regeneration at The University of Manchester, Vitreoretinal Surgeon
at MREH and Director of the Manchester Vision Regeneration (MVR)
Lab, has been working with Second Sight Medical Products Inc. to
trial the company's Argus® II Retinal Prosthesis System with
patients who have retinitis pigmentosa.
Professor Stanga first implanted it in patients in 2009 as part
of a small group of leading surgeons worldwide involved in a
clinical trial of the device. The initial aim was to restore a
basic level of useful vision, in the form of spots of light and
shades of light and dark.
The device consists of a tiny camera and transmitter mounted in
a pair of glasses. This camera transmits a wireless signal via a
small processing device to an ultra-thin electronic receiver, an
electrode panel that is implanted in the eye and attached to the
retina. The electrodes are intended to stimulate the remaining
retinal nerves, allowing a signal to be passed along the optic
nerve to the brain, which perceives patterns of light and dark
spots corresponding to which electrodes are stimulated.
Argus II is the first treatment for severe to profound outer
retinal degeneration to be approved for use in the European Union.
The largest clinical trial of a retinal prosthesis to date has
shown that the device can reliably withstand long-term implantation
(> 5 years) while offering a positive benefit/safety
profile. Patients have shown clear improvements in visual
function and the system has a had positive impact on their daily
Professor Stanga presented the findings of his work with a group
of patients. He tested four blind patients fitted with Argus
II to find out if they could consistently perceive different
colours at the same time.
Different pairs of electrodes on the implanted electrode array
were directly stimulated simultaneously with trains of electrical
pulses at different frequencies and intensities. The patients
reported perceiving colours after each stimulation. This
demonstrated for the first time that patients blinded by outer
retinal dystrophies are able to perceive simultaneous colours using
the retinal prosthesis system.
"Seven different colour combinations were perceived by the
patients, though not all of them saw all the colours", said
Professor Stanga. "Last year we demonstrated that patients with
Argus II could perceive colours, but now we have shown that they
can perceive two colours at once. This data is encouraging because
it suggests the possibility that the device will one day restore