The Great Debate in 18th Century Ophthalmology: Couching

The intricate and elegant phacoemulsification technique that is practiced around the world today has a rich history and fascinating evolution. Prior to the 18th century, the only known approach to treating cataract was through couching, a technique that involved depressing the lens into the vitreous of the eye using a needle. Following the introduction of the extraction, a long and vigorous debate ensued regarding which was the superior method. Two prominent English surgeons who were involved in this debate were Samuel Sharp and Sir Percival Pott. The fascinating clash of ideas between Sharp and Pott highlights that academic debate occurred in early ocular surgery and was important in ultimately advancing the field. Corresponding Author: Faazil Kassam, MD Research Fellow Department of Ophthalmology University of Alberta 2319, 10240 Kingsway Avenue NW Edmonton, AB T5H 3V9 780-994-8930 Email: [email protected], [email protected] It is generally accepted that the beginning of the modern cataract operation occurred with Jacques Daviel on April 7, 17513 when he devised a procedure to remove, or extract, the lens from the posterior chamber of the eye.1,4 This new surgical approach prompted a century-long debate of whether couching or extraction was a superior method of treating cataracts.1 Two English surgeons involved in this period of debate (among many others across Europe) were Samuel Sharp and Percival Pott. Ophthalmic procedures were only a small portion of the procedures both these surgeons performed, as at this time the concept of specialization had not yet taken hold. Sharp (~1700-1778) was a well-known surgeon amongst the London academic circles and did much to pioneer the treatment of eye diseases, including cataracts.4 He was not a degreed practitioner but trained via apprenticeship under the great surgeon William Cheselden and became independent in 1731.4 Percival Pott (1714-1788) ranked among the leading surgeons of his day, and is remembered with his eponyms of Pott’s fracture and Pott’s disease. He is also recalled as first to recognize an occupational cancer, noticing scrotal cancers arising in chimney sweepers.5 Pott, like Sharp, had no academic training; he entered into surgical apprenticeship at the age of 15 under Edward Nourse and completed his training in 1736 with an appointment as assistant surgeon at St. Bartholomew’s hospital in 1745.6 What is perhaps less well known is Pott’s involvement in ophthalmic surgery with regard to cataracts: he was strongly opposed to the extraction method for cataracts.1 Sharp and Pott had a fascinating difference in viewpoints regarding whether extraction or couching was the superior method and both shared their insights and experiences in surgical publications. This rich, academic debate early in ocular surgery highlights the importance of probing, questioning, and refining in order to ultimately spur innovation and advance the field.