A brain implant is still restoring sight three years on — and getting better

When the PRIMA device went in, its wearers were legally blind from geographic atrophy, the advanced stage of age-related macular degeneration. The idea is beautifully simple: a tiny implant under the retina plus a pair of special glasses that stand in for the light-sensing cells the disease destroyed. Now the 36-month results from the PRIMAvera clinical trial are in, presented at the EURETINA Congress in Vienna by Moorfields and UCL surgeon Mahi Muqit — and the restored form-vision has not faded. It is, in Muqit's words, working better at month 36 than it was at month six. The device is already available to patients in Europe and the UK, with US regulatory review pending.