Two patients regain sight following retinal implants

Two patients have regained partial eyesight thanks to the successful execution of a surgical procedure to embed retinal implants into them.

A team at King’s College Hospital, led by eye surgeon Tim Jackson, carried out retinal implant surgery on a patient last month, in tandem with Prof Robert MacLaren at the Oxford Eye Hospital.

Kings and the Oxford Eye Hospital are two centres taking part in a UK trial of a retinal implant for patients with the degenerative eye condition retinitis pigmentosa.

Both patients — who had no vision prior to surgery — are said to be doing well.

In a statement, Kings said they were able to detect light immediately after the retinal implant microchip was activated. Further testing has shown that both patients are able to locate white objects on a dark background. Over the coming months, the patients will undergo further testing as they adjust to the microchip.

The UK trial of the device is set to include 12 patients in total and is being led by the two centres.

Jackson and MacLaren said: ‘We are excited to be involved in this pioneering subretinal implant technology and to announce that the first patients implanted in the UK were successful. The visual results of these patients exceeded our expectations.

‘This technology represents a genuinely exciting development and is an important step forward in our attempts to offer people with retinitis pigmentosa a better quality of life.’

King’s patient Robin Millar, a 60-year-old from London who was one of the two patients to be implanted, said: ‘Since switching on the device, I am able to detect light and distinguish the outlines of certain objects.

‘I have even dreamt in very vivid colour for the first time in 25 years, so a part of my brain that had gone to sleep has woken up.’

Clinical trials

Retina Implant’s subretinal implant technology has been in clinical trials for more than six years. Patients involved in Retina Implant’s clinical trials have received a 3 x 3mm² microchip with 1,500 electrodes implanted below the retina.

Results from the Reutlingen-based company’s first human clinical trial, published in Proceedings of the Royal Society B in November 2010, showed that placement of the implant below the retina, in the macular region, provided optimum visual results, allowing patients to recognise foreign objects and to read letters to form words.

The second human clinical trial, in which patients were implanted with Retina Implant’s new wireless device in Germany, beginning in May 2010, indicated improved visual acuity. The multi-centre phase of this trial was expanded late last year to include two additional sites in Germany, Hong Kong and the UK. Sites in Italy and Hungary are also under agreement to participate.

Data from the first nine patients implanted in Germany in this current trial indicate the best visual acuity to date, with the majority of patients said to be experiencing restoration of useful vision in daily life. The vast majority of patients are experiencing visual perception indoors and outdoors in both dim and bright environments. Additionally, patients have reported the ability to see objects 30ft (9m) away and to read numbers on a pair of dice.

Eligibility

Anyone wishing to apply for the King’s College Hospital Trial should obtain a referral from their GP or ophthalmologist to Tim Jackson, provided they are:

  • Aged 18–78 years
  • A UK citizen
  • Experiencing total or almost total sight loss due to retinitis pigmentosa
  • Blind now but previously had at least 12 years of vision


Anyone who has enough vision to see shapes or objects will not be eligible.