Ridley, Harold (1906–2001)

English ophthalmologist who pioneered the implantation of artificial lenses in cataract surgery. He performed the first such surgery, using a Perspex intraocular lens, in 1949. The procedure was perfected during the late 20th century and has been used to treat hundreds of millions of cataract patients around the world.

Ridley was an ophthalmology surgeon and consultant at Moorfields Eye Hospital and St Thomas' Hospital, London, from the 1930s until his retirement in 1971. His treatment of wounded Royal Air Force pilots during World War II led to his revelation about artificial lenses. He discovered that shards of Perspex from the cockpit lodged in their eyes after crashes were not rejected. From this, he theorized that plastic lenses could be successfully implanted in eyes after the removal of cataracts.

Ridley was born in Kibworth, Leicestershire, England, and attended Charterhouse School, an independent school for boys, in Godalming, Surrey. After studying at Pembroke College, Cambridge University, 1924–27, he completed his medical training at St Thomas' Hospital, London, in 1930. During early World War II he served in the Royal Army Medical Corps in the Gold Coast (now Ghana), where he did important research on onchocerciasis, a local tropical disease that was the leading cause of blindness. He was knighted in 2000.