Ocular Manifestations of Sickle-Cell Disease

Abstract

The tendency for red blood cells to assume a sickled shape under conditions of low oxygenation has been demonstrated predominantly in the Negro race.¹Patients exhibiting this phenomenon have been classified as having sickle-cell trait, an asymptomatic carrier state, or sickle-cell anemia, a hemolytic disease with occlusive vascular complications and shortened life span. Renewed clinical interest in these entities has followed recent developments in the study of human hemoglobins. In 1949, Pauling, Itano, Singer, and Wells²proved by means of electrophoresis that the hemoglobin in patients with sicklecell anemia (sickle-cell hemoglobin, or hemoglobin S) differs from normal adult hemoglobin (hemoglobin A). Furthermore, familial electrophoretic studies²and the genetic investigations of Neel³established the hereditary basis for the sickling phenomenon. The inheritance of the gene for sicklecell hemoglobin from one parent and the gene for hemoglobin A from another parent, constitutes the sickle-cell trait and represents a