Historical Background

In 1847, the English mathematician and inventor Charles Babbage showed a distinguished ophthalmologist his device for examining the inside of the eye, but unfortunately this was never exploited and it was not until 1851 that Hermann von Helmholtz published his classic description of his instrument, the ophthalmoscope. He developed the idea from his knowledge of optics and the fact that he had previously demonstrated the "red reflex" to medical students with a not dissimilar instrument. In principle, he had, for the purposes of his demonstration, looked through a hole in a small mirror, which reflected light from a lamp into the subject's eye. This produced the red reflex in the pupil well known to photographers and night drivers and no doubt this fascinated medical students at that time. Von Helmholtz worked out that a similar device could be used to inspect the inside of the eye. According to correspondence of the time, it took him about a week to learn the technique of examining in detail the structures within the eye and he wrote a letter to his father telling him that he had made a discovery that was "of the utmost importance to ophthalmology". Soon after this, a mass of descriptive information on the optic fundus appeared in the scientific literature and modern clinical ophthalmology was born. The changes in the eye associated with systemic diseases such as hypertension and anaemia became recognised. Several blinding conditions limited to the eye itself, such as glaucoma and macula degeneration, were also described at this time.

But we must not belittle the developments that had occurred before the invention of the ophthalmoscope. In the eighteenth century, considerable advances had been made in the technique and instrumentation of cataract surgery, and the science of optics was being developed to enable the better correction of refractive errors in the eye. If we go back to the seventeenth century, the existing ophthalmological services were definitely limited, as is revealed in the writings of the famous diarist, Samuel Pepys. Although we have no record of his eye condition other than his own, he did consult an oculist at the time and unfortunately received little comfort or effective treatment. His failing eyesight brought his diary to an abrupt end in spite of the use of "special glasses" and the medicaments, which caused him great pain.

Although records of eye surgical techniques go back as far as 3000 years, modern eye surgery was largely developed thanks to the introduction of cocaine and then of general anaesthesia at the end of the nineteenth century. The use of eserine eye drops to reduce the intraocular pressure in glaucoma was introduced at the same time, this being the forerunner of a number of different medical treatments that are now available. Cataract surgery saw great advances at the beginning of the twentieth century, with the introduction of the intracapsular cataract extraction. In the 1920s, successful attempts were being made to replace the detached retina, which had previously been an irreversible cause of blindness. Such early surgical techniques have now been developed to produce some of the most dramatic means of restoring sight. As a spin-off from the last war came a revolutionary idea of "spare-part" surgery in the eye. The observation that crashed fighter pilots were able to tolerate small pieces of perspex in their eyes led to the use of acrylic intraocular implants, the lens of the eye being replaced by an artificial one. Such spare-part surgery has now become commonplace, as will be seen in Chapter 11. The operating microscope was introduced in the 1960s, and with it came the development of fine suture materials and the use of instruments too small for manipulation with the naked eye. This in turn has led to small incision techniques and sutureless surgery, which has made the day-case cataract operation a routine. Forty years ago, the vitreous was a surgical no-man's land, but instruments have now been developed that can cut, aspirate and inject fluid simultaneously, all these procedures being carried out through fine-bore needles. Membranes, blood or foreign bodies can now be removed from the vitreous as a routine. Much important eye disease is inherited and it is not surprising that very important advances have occurred recently in the field of ophthalmic genetics. The gene controlling the development of the eye has now been identified and perhaps the answer to the tragic problem of inherited degenerative retinal disease is on the horizon.

In the early days of the development of the specialty, a number of specialised hospitals were built throughout the UK. The first of these was Moorfields Eye Hospital, founded largely to combat the epidemic of trachoma, which was prevalent in London at the time. Subsequently other eye hospitals appeared in the main cities of this country, often the result of pressures of local needs such as the treatment of industrial accidents. In recent years, there has been a tendency for eye departments to become incorporated within the larger district general hospitals, although individual eye hospitals remain and are still being built.

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