Ahana Sen, Third Major, Grant Govt Medical College
We all know about cataract. We’ve all seen it. As children we’ve observed the white spot in the black part of the eye of our elders and now as medical students we know that cataract has many causes and could occur in children, adults and elderly.
The word ‘Cataract’ stems from the Greek word ‘katarraktes’ meaning ‘waterfall’. People believed that cataracts comprised of an ‘abnormal humour’ that developed and flowed in front of the lens to decrease the vision.
Now, cataract refers to the development of any opacity in the lens and its capsule which is of sufficient severity to cause impairment of vision.
There is a statue of a man in some Egyptian museum in Cairo with a left white eye. Created about 2457-2467 BC, it is believed to be the oldest documented case of cataract demonstrating left white pupillary reflex.
As is natural with humans, they try to fix something they find wrong.
Thus the first form of cataract operation was performed in ancient India. Described by an ancient Indian surgeon, Maharshi Sushruta who described the procedure in ‘Sushruta Samhita’, it is known as ‘couching’and consists of moving the cataractous lens away from the pupil, and letting it sit in the vitreous cavity towards the rear of the eye. The eye would later be soaked with warm clarified butter and then bandaged. This surgery was believed to be introduced in the West by Greek travellers from India and Middle East.
The first references to cataract and its treatment in the West are found in 29 BC in De Medicinae by Celsus. This also describes the couching operation. ‘Needling’ or ‘discussion’ was also discussed where the cataract was sliced into multiple particles, allowing them to be easily absorbed.
Finally, the cataract surgery where cataract was actually removed was introduced by Jacques Daniel in Paris. He performed the first Extracapsular Cataract extraction on April 8, 1747. In this form of surgery, the substances from the inner lens are extracted, yet part of the outer covering remains.
Many improvements occurred during the 20th century with discussion of ‘couching’ vs ‘extracapular lens extraction.
A huge breakthrough occurred in the 1940s in England when Harold Ridley created the IOL- long lasting plastic lens fixed inside the eye as a substitute for the crystalline lens.
Sir Nicholas Harold Lloyd Ridley was an English ophthalmologist who pioneered artificial intraocular lens transplant surgery for cataract surgery. He was dissatisfied with the poor acuity and loss of binocular single vision following unilateral cataract extraction and the poor with the contact lens then available. This led to the idea of an artificial lens. The problem was choosing an inert substance that would be used as an intraocular foreign body.
Fortunately, he was inspired in his choice of polymethylmethacrylate (PMMA) which became the gold material of implant material. He observed the eyes’ tolerance of PMMA following eye injuries in Royal Air Force pilots. When the pilots’ plastic canopies were struck with bullets, they shattered leaving pieces of PMMA in their eyes. It was seen that the pilots’ eyes were compatible and did not reject the inert PMMA substance.
Despite facing strong opposition from the medical community, Ridley developed many comprehensive programmes for cataract surgery with IOL implants.
At long last, in 1967, Charles Kelman introduced ‘Phacoemulsification’- the method we mostly see in the hospital. Funnily enough, he was inspired by his dentist’s ultrasonic probe. This technique used ultrasonic waves to emulsify the nucleus of the lens in order to remove the cataracts without a large incision.
Since then there has been dramatic increase in the popularity of Phacoemulsification and why not?
Small incision, less hospital stay, less complications…
As we have seen, cataract surgery is a procedure which have been described, modified and described again since ancient times. There have been rapid improvements only recently. There have also been advancements in different areas like the IOL, viscoelastic substance, improved surgical techiniques, etc- all of which promise to further improve the patient’s outcome in the future.