Aniridia and Related Iris Defects:  A Report of Twelve Cases with Bilateral Cataract Extraction and Resulting Good Vision in One

Aniridia or irideremia is a clinical term denoting absence of the iris in whole or in part. Actually, total absence has not been reported, as there has been rudimentary iris tissue in all cases reported in the literature. Because of the ease of investigation, aniridia has been extensively studied by geneticists. Several theories have been advanced to account for this condition, chief among which are the mesodermal theory of Ida Mann¹ and the ectodermal theory. Duke-Elder² believes that both are operative, in different cases. Series have been reported which would make the defect appear to be recessive, on the one hand, while other series would indicate that it is dominant. According to Callahan,³ it is generally inherited from affected members in proportion of approximately 50% Occasionally a single case is seen in some family where there is no other history of eye disorders; these have been variously