It’s a strange phenomenon that some of the most revolutionarily successful people are initially rejected, scorned or unappreciated. Galileo, van Gogh, Darwin, Lovelace, Mendel and Austen were all vastly unpopular in their time, yet now we all take their scientific and creative contributions for granted. Sir Harold Ridley, the inventor of the intraocular lens, is another example of these late-sung heroes. His work saves the eyesight of millions of people across the world every year, but at first his idea of placing a plastic lens onto the surface of the eye was thought by peers to be impossible, laughable and even dangerous.
The eyeball acts like a camera: light from the outside travels through the pupil and the lens to focus on the back of the eye, where the light is translated into images by light-sensitive cells that are located there. Due to age, trauma, toxic chemicals or certain diseases such as rubella or diabetes, the proteins that make up the lens denature and become opaque which prevents light from entering the eye and causes cataracts. People with cataracts suffer from very poor vision or blindness (see the image comparison); over half the world’s blindness (around 20 million people) is caused by age-related cataracts alone.
Over the course of history, several gory approaches to treating cataracts have been trialled. Somewhere between 2000-600BC, a procedure called ‘couching’ was used. This procedure involved using a sharp instrument, or just blunt pressure, to detach the cataract-riddled lens from where it normally resides into the back of the eye. Not surprisingly, this procedure was usually massively unsuccessful: patients usually suffered pain (as this was before a lot of modern anaesthetics were available), inflammation, infection and even blindness as a result. Even if the procedure and aftercare went smoothly, the patient was still left with inadequate eyesight. Unfortunately, couching is still performed in some developing countries where access to healthcare is often restricted.
As general surgical practice improved over the centuries, better tools and instruments were developed that allowed the opaque lens to be either removed, or broken up into small, more easily absorbable pieces. More often than not, patients were still left with poor eyesight and had to wear cumbersome, thick glasses to compensate for the missing lens.
Dr Harold Ridley, a recently trained medical doctor who specialised in ophthalmology, worked in the south of England during the Second World War. In August 1940, Flight Lieutenant Gordon ‘Mouse’ Cleaver forgot to put on his flight goggles before going out in his plane for what was to be Adlertag (Eagle Day) – the first day of Luftwaffe’s mission to eliminate the Royal Air Force from the sky. On returning to base, a bullet went through the side of Cleaver’s cockpit and shattered the Perspex window, a small fragment of which entered his eye. Cleaver had many operations on his face to treat the damage, but Dr Harold Ridley’s operation was to change medical history.
When Ridley removed the Perspex from Cleaver’s eye, he observed that there was no inflammation: the body hadn’t recognised the material as ‘foreign’ and so hadn’t initiated an immune response against it (as it usually does against materials like wood or metal). Ridley started thinking: if you could take the Perspex out of eye and there was no inflammation, then there would surely be no biological reason why you couldn’t put it back in.
With this in mind, Ridley developed the first intraocular lens (IOL) – a small disc made from Perspex – and in 1949 placed it into the eye of his patient after first removing her cataract. With further modifications to improve the IOL’s power (that is, the ability of the lens to bend light, as glasses do), some of his first patients even attained 20/20 vision. Initially, Ridley sought to keep his patients’ implants a secret from the academic community until he could confirm from follow-up checks that there were no adverse effects, but a patient accidentally let slip the secret. So, in 1951 Ridley published his results and took two of his patients to be inspected by the Oxford Ophthalmological Congress. His work was rejected by other eye experts and deemed heretic. As a result, Ridley became a professional pariah and sank into depression.
But not everyone was so sceptical about the IOL. Foreign eye doctors saw the promise of the invention and in 1974 – 25 years after the first IOL implant – a Club was started with the aim of discussing the use of IOLs in cataract surgery. Robert Young, a famous American actor, underwent the procedure and sang its praises to the press. Only years after he retired in 1971 was Harold Ridley officially recognised by the ophthalmic societies and institutions. In 2000 he was knighted by Queen Elizabeth, but he passed away in 2001.
The long-unappreciated work of Harold Ridley is now recognised as not just an invaluable contribution to ophthalmic medicine, but also one of the first ever feats of bioengineering. Applying a scientific strategy such as using materials that are foreign to the body to fix a medical problem was previously unheard of, yet today we benefit from IOLs, dental implants and pacemakers to name just a few. Increasingly, bioengineering takes advantage of 3D printing and other advancing technologies and materials in the production of tissue grafts and implants that, like IOLs, will make such a huge difference to peoples’ lives.
Post by Natasha Bray