On September 16 Royal Mail issued a new set of stamps entitled 'Medical Breakthroughs'. It celebrates major turning points in 20th-century British medicine. One of the six stamps (67p) commemorates Sir Harold Ridley's invention of the intraocular lens (IOL) and the surgery to implant it, thus effecting the first-ever total cure for cataract.
Ridley is in good company. The subjects for the stamps were whittled down to the final six, covering different areas of medicine, from a shortlist of 20 drawn up by the medical historian Professor Dorothy Porter. The other five stamps depict Sir James Black's synthesis in 1962 of artificial beta-blockers (standard first class rate) Sir Alexander Fleming's discovery of penicillin in 1928 (58p) Sir John Charnley's development of the hip-replacement operation, first performed in 1962 (60p) Sir Ronald Ross's discovery of the malarial parasite in, and its transmission by, mosquitoes in 1897 (88p) and Sir Godfrey Hounsfield's research that led to the invention of the CT scanner in 1971 (97p).
Ridley also joins a select few ophthalmologists to have been illustrated on postage stamps. These include Donders (Netherlands, 1935), Purkinje (Czechoslovakia, 1937) and Helmholtz (East Germany, 1950). To see why Ridley deserves to be in such exalted company it is worth looking again at the story of the man and his visionary invention.
November 29 1949. That is the momentous date, the day the world's first operation to implant an IOL was performed, by Harold Ridley at St Thomas' Hospital in London. Those who have seen the commemorative plaque in the hospital will have noted a different date given - February 8 1950. There is some confusion in the hospital records as to whether the IOL was implanted at the same time or not as the cataract extraction. The senior nurse attending, who was entrusted with the crucial role of illuminating the eye with a hand-held torch insists that it was. In any case, the earlier date certainly marks the start of the whole procedure. It was the culmination of an idea that Ridley had been considering since the 1930s.
The story often told about the genesis of the idea for an IOL involves a 'eureka' moment for Ridley, after he observed that plastic shards from shattered aeroplane canopies embedded in World War 2 fighter pilots' eyes remained inert and no infections resulted. In fact, the observation was one, albeit crucial, step on a path that Ridley had been exploring in thought and in conversation with colleagues for several years. By 1940 he, along with much of St Thomas', had been evacuated to locations across southern England. The region where Ridley worked was near RAF Tangmere, an important base close to the Sussex coast, whose squadrons were heavily involved in the Battle of Britain. On August 15 1940, Flight Lt Gordon 'Mouse' Cleaver of 601, County of London, Squadron was shot down in combat over Winchester. His Hurricane's canopy was shattered and his eyes were filled with perspex splinters, but he managed to return to Tangmere. He was completely blinded in the right eye, but some vision was retained in the left.
Following initial examination by military surgeons he was sent to Moorfields. In all he had 18 operations on his eye and face, some of which Ridley probably performed. During years of follow-up Cleaver in effect served as Ridley's pre-clinical trial for a material suited to making an IOL. An employee of Rayner & Keeler, who manufactured the first IOL, wrote in 1949: 'Everyone is aware by now of Mr Harold Ridley's recognition that this material [perspex] in the eye of service personnel appeared to cause no inflammatory condition, and in most cases, could be left alone as harmless intraocular foreign bodies.' ICI produced a pure form of their PMMA material used in aircraft cockpits which they called Perspex CQ (clinical quality) for those first IOLs. The 'Ridley IOL' was a biconvex lens of 8.35mm total diameter including a peripheral ridge designed to help grip the IOL as it was inserted into the lens capsule.
Unfortunately for Ridley, he had to announce the results of his early implant operations sooner than he would have wished after news of his procedure leaked out when a patient mistakenly made a postoperative appointment with an ophthalmologist namesake. Having published articles to establish priority, recounting the procedure and detailed follow-up, Ridley decided to make his first major presentation at the prestigious Oxford Ophthalmological Congress in July 1951. He was optimistic about the response he might receive, especially as the two subjects he took along with him enjoyed vision of 6/6 or better 18 months postoperatively. Instead it was to mark the start of a 30-year period of setbacks and depression for Ridley in the face of implacable hostility from influential figures, notably Sir Stewart Duke-Elder, when the idea and practice of IOLs fell almost into disuse. The idea of inserting a foreign body into the eye was before its time.
A few people kept the flame alive during this time. A protégé of Ridley's, Peter Choyce, provided invaluable support and research at some cost to his own advancement. Abroad, Fyodorov in Russia, Epstein in South Africa and Binkhorst in the Netherlands were notable supporters. There was also pioneering work being carried out in the USA. There were many complications with IOLs, however, but mostly these were due to poor design and manufacture and, in some instances surgical technique. As recently as the mid-1980s opposition to IOLs was strong, and Ridley's health and career had been severely affected by the negativity surrounding his invention. But then a landmark paper was published in Ophthalmology (Vol 91, pp 403-419, 1984) entitled Anterior Segment Complications and Neovascular Glaucoma Following Implantation of a Posterior Chamber Intraocular Lens by Apple et al. The main recommendation of the authors was that the entire IOL should be placed within the capsular bag - just as Ridley had advocated. Complications were vastly reduced, and the attitude to IOLs rapidly began to change.
This seminal paper was the result of a removed IOL being sent to Dr Apple, an ophthalmologist and pathologist, for analysis at his laboratory in the University of Utah's ophthalmology department after complications had arisen in the subject eye. A follow-up article, Complications of IOLs: a Historical and Histopathological Review (Survey of Ophthalmology, Vol 29, pp 1-54, 1984) more fully catalogued the various IOLs and their complications. It became one of the most reprinted articles in ophthalmology literature and as a result interest in IOLs exploded. When these papers were brought to Ridley's attention, he realised that his idea was finally about to achieve mainstream acceptance. The IOL has now restored vision to over 200 million people worldwide, and approximately 10 million IOLs are implanted annually.
There are a couple of interesting postscripts to the story. 'Mouse' Cleaver, the subject of Ridley's pre-clinical trial, had suffered a traumatic cataract in his remaining eye as a result of his original injuries. By the mid-1980s, after long-term follow-up, it was felt that he was ready to have the cataract removed and receive an implant. His sight was restored thanks to research on his own eye 40 years earlier, with a device of similar material to that which caused his injuries. Ridley himself finally gained public recognition, with election to fellowship of the Royal Society, and a knighthood. Sir Harold Ridley, FRCS, FRS (1906-2001) also latterly received the benefit of his own invention. ●
● David Baker is an independent optometrist