ON THE INCIDENCE OF CLOSED‐ANGLE GLAUCOMA IN SOUTHERN NORWAY

The primary glaucomas may be divided into two groups: 1 ) Closed-angle glaucoma, where the rise in tension is caused by blockage of the chamber angle, and 2) Open-angle glaucoma, where such a blockage does not take place. This classification is a logical consequence of the view that the two groups represent a different etiology and pathogenesis, and partly demand different treatment . The incidence of the two groups seems to vary considerably in different countries. In a recent paper from England R. Smith (1958) finds that the closed-angle group amounts to over 50 O/O of the primary glaucomas. In fact he finds a percentage of 73 in a specially designated group. In his material the acute glaucomas constitute about the half of all closed-angle cases. Among Norwegian ophthalniologists it is a common view that closed-angle glaucoma is less frequent in this country than abroad. Holst (1947) has gone through the records of 2167 primary glaucomas treated in the University Eye Department, Rikshospitalet, Oslo, in the period 1920-39. He found the proportion 6,6 O/o glaucoma inflammatorium and 93,4 O/o glaucoma simplex. For the three-year period 1955-57 Professor Thomassen has given me the figures from the same department: 449 primary glaucomas, of which 30 acutum and 419 simplex, thus again 6,6 O / o and 93,4 O/O respectively. When I started practising in the most southern part of Norway 4 years ago, I gradually got the impression that closed-angle cases were more frequenb than I was used to from other parts of the country. I therefore became interested in finding out the real frequency of closed-angle glaucoma among my patients. The material consists of all cases with primary glaucoma which I have seen the last 4 years, in all 152 patients. Many of them were advanced cases, some seen only once and many operated on before by others. A definite classification may then be impossible. When counting only those cases which have got the diagnosis for the first time by me, one probably will get a better expression