Sorsby's fundus dystrophy. A clinical study.
A survey was undertaken of a family known to have Sorsby's fundus dystrophy. Fifty members were reviewed, and 14 were found to be affected. Many of Sorsby's original conclusions were confirmed, including the pattern of inheritance and age of visual loss. Yellow material was present at the level of Bruch's membrane early in the course of the disease. However, the earliest phenotypic marker was delayed filling of the choriocapillaris. Abnormalities of choroidal perfusion became more profound and extended centrifugally with time. The loss of central vision was commonly due to atrophy of the outer retina and choroid. Subretinal neovascularization was a rare occurrence. The homology between this dystrophy and age-related macular disease underlines the importance of the clinical findings in this family.