Cataracts are regions of dead cells within the lens, which turn the lens opaque, thereby blocking the light and often resulting in blindness. The Ancient Greeks were the first to operate on cateracts, using a needle to pierce the eyeball and knock the lens to one side. At the turn of the century, the operation was more or less the same, but the aim was to completely remove the murky lens. But without a replacement lens, vision was still poor, and most patients were unable to work.
Surgeons had tried to insert a replacement glass lens, but experience had shown that it was inevitably rejected. Dust or sand on the surface of the eyeball can cause enormous irritation, so it is not surprising that a foreign object inside the eyeball is problematic. However, in the 1940s one British eye-surgeon questioned the orthodoxy and proved that artificial lens implants were feasible.
Harold Ridley was born in 1906 into a medical family. His childhood memories include being bounced on the knee of Florence Nightingale. After the Second World War, he encountered several fighter pilots who had suffered eye injuries, caused by the splinters from shattered cockpit canopies. Spitfire pilots in particular seemed to suffer from canopy splinters embedded in their eyeballs. Ridley noticed to his surprise that these splinters did not cause any severe problems. They sat quietly in the eye without causing inflammation and without being rejected. The reason for this was that the canopies were made of Perspex, a material that is so inert that that the eyeball accepts it.
In 1948 Ridley planned to implant a Perspex lens into a patient, and held a series of clandestine meetings with John Pike of Rayner, an optical company based in Brighton. It was so widely accepted that implants would not work that they chose to meet in Cavendish Square in the back of Ridley's car. The first operation took place in 1949. Although it was successful, the implant was kept secret until 1951, because it was obvious that it would be considered a highly controversial operation.
Ridley did not patent his idea, because he was determined that the benefits of his work should not be constrained by financial considerations. It has been exactly 50 years since the first operation, and millions of people around the world owe their sight to Ridley's idea. Now 92, he lives near Salisbury with his wife, Elizabeth.