He led the first St Vincent's Hospital civilian surgical team to work in Long Xuyen, Vietnam, during the Vietnam War.[1]
In September 1986 he delivered the Hunterian Orationondiverticular disease. In 1988, he published A Very Short Textbook of Surgery, and this was also translated into Indonesian and Mandarin. He also worked as an honorary consultant surgeon one morning per month for almost 20 years from 1981 at the VAHS (Victorian Aboriginal Health Service).[1]
Another of his medical lifetime interests was road safety and driving. He was a founding member of the Royal Australasian College of Surgeons' Road Trauma Committee,[3] which was partially responsible for the introduction of compulsory seat belts in cars in Victoria in 1970, the first state in the world to pass such a law (Seat belt legislation). In May 1965 Ryan supported a motion to investigate the causes of road accidents in Australia.[4]
Ryan was President of the International Society of University Colon and Rectal Surgeons (ISUCRS) from 1987 to 1988, and chaired the ISUCRS Congress in Melbourne in 1980.[1]