Intraocular lenses are artificial lenses implanted in the eye. They were originally used to simply replace the natural lens removed during cataract surgery, but now they are so advanced.
They can also correct a variety of prescriptions, including myopia (short sightedness), presbyopia (reading problems arising with age) and astigmatism (uneven curvature of the eye).
Before the introduction of intraocular lenses (IOLs), people who had their own lenses removed during cataract surgery had to wear very thick glasses afterwards to enable them to see, as the lenses couldn’t be replaced. While cataract sufferers had their sight restored, the glasses were heavy and inconvenient. Unfortunately, at the time, there seemed to be no other solution.
Harold Ridley, an ophthalmologist at St Thomas’ Hospital in London, implanted the first intraocular lens on February 8, 1950. Up until this point, no one had been able to carry out such an operation because it was considered unsafe and unwise to insert a foreign object into the eye due to inflammation and the body’s response. However, during World War II, Ridley had observed that Spitfire pilots who sustained eye injuries when their perspex canopies shattered didn’t suffer the same pain and inflammation as people whose eye injuries involved conventional glass. By happy accident, he had found a suitable material for intraocular lenses.
Sadly, when Ridley revealed his pioneering surgery publicly in 1950, it met with opposition and derision. Whether this was because of professional jealousy on the part of the ophthalmic community, or because they thought the procedure was too risky, we will never exactly know – I suspect it was a combination of the two. The effect of this bad reception was to delay the advance of IOL surgery, which only became a standard procedure in the 1970s.
Nowadays, IOLs are made from silicone and acrylic compounds, both of which can be used to create a flexible lens. The flexible lens carries fewer complications compared with the old perspex lenses and can be delivered through a much smaller wound allowing for visual recovery within days of the procedure.
Developments in materials also mean that IOLs can now be used to correct short and long-sightedness, through a procedure called refractive lens exchange . While the LASIK (laser vision correction ) procedure is one of the safest and most effective solutions for people with poor eyesight, it isn’t suitable for every prescription. People who have both hypermetropia and presbyopia, for example, or those with very high myopia, will achieve better results with IOLs than with LASIK in certain instances. Hence the need for individualised treatment.
Since the first procedure conducted by Harold Ridley in post-war London to the present day, millions of people worldwide have benefited from IOL surgery.
In his later years, Harold Ridley was knighted in February 2000 for his amazing contribution to cataract surgery and as fate would have it underwent cataract surgery himself with replacement lenses – lenses which without his ingenuity and perseverance may never have been developed.