The History of Cataract Surgery
Cataract surgery is often cited as one of the most successful surgical interventions. It has changed the lives of millions of people. The surgical technique has been refined over many years delivering fantastic surgical results with very low rates of complications.
Cataract surgery in its simplest form is at least 4000 years old. The earliest method known was couching. This method involved applying pressure digitally or via a sharp needle to the cataract and dislocating it into the posterior part of the eye known as the vitreous. There was no replacement of the lens and patients were left with a large focussing error known as aphakia. There was little regard for the prevention of infection by sterilisation of instrumentation and no anaesthesia. Complications such as chronic inflammatory scarring were common and patients were often left blinded. Couching is still performed in some parts of rural Africa and Asia today.
Cataract surgery became more refined with a better understanding of the anatomy of the eye. In 1747, a French ophthalmologist called Jacques Daviel pioneered a technique called extracapsular cataract surgery. This involved a more precise incision into the inferior part of the cornea and an opening to the anterior lens capsule. Saline irrigation allowed the cataract to be expressed forward through the corneal wound leading to far fewer complications.
Other variations on this technique were also developed. In 1880 Smith removed the whole capsule and cataract in a technique called intra-capsular cataract extraction.
In 1949, Sir Harold Ridley made the groundbreaking observation that plexiglass fragments from Spitfire canopies remained inert in the eyes of injured fighter pilots. As a result he designed the first Perspex intra-ocular lens designed to replace the cataract and restore the focussing ability of the eye. This was supported on the posterior capsule which was left after extra-capsular cataract surgery.
Various other intra-ocular lens designs were introduced based on different compositions and positioning within the eye. In 1950, the introduction of cortisone and antibiotics reduced the complications of inflammation and infection significantly. Improved stitching material allowed better wound healing too.
In 1967, Charles Kelman adapted dental instruments to emulsify the cataract within the anterior chamber in a technique known as phaco-emulsification. This is still the modern day method to remove cataracts. Intra-ocular lens designs today can correct for one distance – monofocal lenses, multiple distances – multifocal lenses and correct for astigmatism – toric intraocular lenses.
In 2001, femtosecond lasers were used to accurately re-sculpt the cornea to correct for refractive errors such as myopia and hypermetropia.
The use of femtosecond lasers in cataract surgery is the most recent new development in surgical technique. The laser can create accurate cornea wounds, precisely open the anterior capsular bag in a near perfect circle and can fragment the cataract within the capsular bag.
Pioneers and innovators have all contributed to the development of a surgical technique that has improved millions of lives.