John Donald MacIntyre Gass (2 August 1928, Montague, Prince Edward Island – 26 February 2005, Nashville, Tennessee) was a Canadian-American ophthalmologist, one of the world's leading specialists on diseases of the retina.
He received in 1950 his bachelor's degree from Vanderbilt University and then served from 1950 to 1953 in the U.S. Navy as an active line officer during the Korean War.
Dr. Gass used that test to characterize the often subtle differences among diseases, combining angiography with other observations in describing the wet form of macular degeneration and refining existing descriptions of other disorders.
In 1967, Dr. Gass helped to describe the most common cause of vision impairment that may follow cataract surgery, a type of macular swelling now known as Irvine-Gass syndrome.
[4] He is also well known for his work in finding the link between acute zonal occult outer retinopathy (AZOOR) and other retinal syndromes and in the treatment of diffuse unilateral subacute neuroretinitis.