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Leber's congenital amaurosis. A retrospective study of 33 cases and a histopathological study of one case.

This report is a retrospective study of 33 patients seen over a 16-year period in whom a diagnosis of Leber's congenital amaurosis was made. The findings of an autosomal recessive heredity in 33%, connatal blindness (visual acuity less than 20/200) in 95%m nystagmus in 75%, and a markedly abnormal electroretinogram in 100% is in agreement with the findings of previously published large series. The difficulty in making the correct diagnosis initially was related to the wide variety of fundus findings and a high association (30%) of central nervous system disease. In the differential diagnosis of connatal blindness, only Leber's congenital amaurosis exhibits an absent or markedly diminished response on electroretinogram. The histopathologic findings in a 6-month-old infant with this disorder are compared with those of previously published reports.