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Advertisement Allvar Gullstrand Encyclopedia Article Find Print E-mail Multimedia 1 item Allvar Gullstrand (1862-1930), Swedish ophthalmologist and Nobel Prize winner. For his important advances in describing the structure and function of the human eye , Gullstrand was awarded the Nobel Prize in physiology or medicine in 1911. Gullstrand was born in Landskrona, and in 1888, while attending the Karolinska Institute in Stockholm, passed all necessary course work and examinations to qualify to practice medicine. Two years later, specializing in ophthalmology, he received a Ph.D. from the same institution. Gullstrand then served as chief physician at the Stockholm Eye Clinic and lectured in ophthalmology at the Karolinksa Institute. In 1894 he moved to the University of Uppsala, where he remained until his retirement in 1927. Gullstrand's early research, presented in his doctoral thesis, concerned an eye disorder known as astigmatism. In this condition, vision is blurred because one of the structures inside the eye, such as the cornea or the lens, is not curved properly and does not correctly focus light waves on the retina at the back of the eye. In his later research, Gullstrand used complex mathematical calculations to determine how the eye focuses on objects both near and far. In particular, he studied how an intricate network of muscles and ligaments makes changes in the shape of the eye's lens in order to focus on objects. For example, to focus on a nearby object, the lens becomes convex in shapeâthat is, curving outward. To focus on objects far away, the lens changes to a concave shapeâcurving inward. The process by which the lens changes shape is known as | |
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