John G. Lindberg and the discovery of exfoliation syndrome.

John G. Lindberg, a young Finnish ophthalmology resident, started a research project in 1914 aiming at an academic dissertation. His plan was to elucidate Axenfeld's observations on iris changes in senile eyes. Axenfeld had described two types of degeneration of the iris: a hyaline degeneration of the iris pupillary zone causing poor pupillary dilatation with mydriatics and an atrophy of the iris pigment epithelium at the pupillary border. For his research Lindberg had to construct a slit-lamp biomicroscope by studying Gullstrand's monograph on the matter; slit-lamp biomicroscopes were not commercially available at that time. A Sach's lamp was used for transillumination of the iris. While conducting his research Lindberg paid attention to greyish flakes and fringes at the pupillary border. He also noted how this strange material formed a membrane on the anterior lens surface. Documentation was made by skillful hand drawings. The new phenomenon was found to be as common in cataract patients as in non-cataractous controls older than 55 years. The phenomenon was observed in 50% of glaucoma patients. Age was the decisive factor; the phenomenon was more prevalent with advancing age. Lindberg published his results as a thesis at the University of Helsinki in 1917. When attending a Nordic Congress of Ophthalmology in 1921, Lindberg met Norwegian ophthalmologist, Birger Malling, and gave him his thesis and explained the new findings. In 1920-21 Lindberg worked at Axenfeld's clinic in Freiburg, Germany. During this period he met in Basel, Switzerland, a Swiss ophthalmologist, Alfred Vogt. He told Vogt about his research and provided him with copies of his thesis. Both Malling and Vogt published papers on exfoliation in 1923 without referring to Lindberg's work. Lindberg did not, however, interfere with these papers. Thus Lindberg was forgotten by his contemporaries as a scientist. However, his main conclusions on exfoliation are still valid today. The life of this remarkable ophthalmologist is described in the present paper.