Cataracts have been known to mankind for centuries. A cataract is a white or cloudy patch that develops in the eye lens, reducing the amount of light that passes through it and leading to blurred vision. The word cataract comes from the Latin word “cataracta” meaning waterfall, with the condition possibly therefore named after the white appearance of rapidly running water.
The earliest documented case of cataract was reported to be in a museum in Cairo that houses a small statue from the 5th dynasty (about 2457-2467 B.C.E.) The wooden statue of a priest reader clearly has a white patch carved into the pupil of the left eye, and is thought to represent a cataract.
Couching
Couching is the earliest surgical procedure to be used in the treatment of cataracts. Several illustrations on the inside of Egyptian temples and tombs depict surgical instruments that indicate the use of couching, a procedure that involved dislodging the eye lens to clear the cataract.
The procedure was first described by Maharshi Sushruta, an ancient Indian surgeon, in his treatise called the “Sushruta Samhita, Uttar Tantra” dating back to 800 B.C.E. The text describes the couching procedure, in which a needle is used to force the lens to towards the back of the eye. The eye would then be soaked with clarified butter and bandaged.
Couching was introduced to China during the late West Han Dynasty (206 B.C.E.-9 A.C.E). Also known of as jin pi shu, the use of the procedure spread throughout China. During the Tang Dynasty (618-907 A.C.E.), jin pi shi became combined with acupuncture and became a part of Chinese medical practice until the formation of the Republic of China in 1911 when the government claimed the procedure was unscientific.
In 1949, when the People’s Republic of China was established, the procedure was encouraged by Chairman Mao who treasured traditional Chinese medicine. After his death however, many Chinese ophthalmologists criticized jin pi shu for its high complication rate and low success rate and the operation is now gradually being faded out.
In the West, the earliest reference to cataract surgery was found in the work of Latin encyclopaedist Aulus Cornelius Celsus, which described the couching procedure in his work De Medicinae of 29 B.C.
Couching is a dangerous and unsuccessful method for treating cataracts, leading to severe complications and complete blindness in most cases.
Cataract extraction surgery
Couching was eventually replaced by cataract extraction surgery, which used a suction device to remove the lens. Bronze oral suction instruments have been found from as early as 2nd century A.C.E. In the 10th-century, Persian physician Muhammad ibn Zakariya al-Razi described the procedure and attributed it to a 2nd-century Greek physician Antyllus.
Jacques Daviel (1696–1762), a French ophthalmologist, was one of the first European physicians to successfully extract cataracts from the eye, with his first operation dated to April 8, 1747. Albrech von Graefe (1828-1870), next described his “modified linear extraction” as a new technique for the removal of cataracts.
Introduction of the artificial intraocular lens
The pioneer of artificial intraocular lens transplant surgery was the English ophthalmologist Sir Nicholas Harold Lloyd Ridley who performed the first procedure in 1949. For the artificial eye lens, Ridley used a material called polymethylmethacrylate (PMMA), which became the gold standard as the substance to use for implant procedures.
Ridley noticed that Royal Air force pilots whose canopies had been struck with bullets seemed to tolerate any pieces of PMMA that had been left in their eyes. On 29 November 1949, Ridley performed the first successful intraocular lens transplant using the material at St. Thomas’s Hospital in London.
Advent of phacoemulsification
Phacoemulsification was introduced by ophthalmologist Charles D. Kelman in 1967. The technique uses ultrasonic waves to break down the nucleus of the crystalline lens so that cataracts can be removed without the need for a large incision into the cornea. With this new method of surgery, patients experienced less pain and could spend less time in hospital.
Further Reading
UEA researchers develop novel resin for 3D printing intraocular devices