In a survey of 78 hearing impaired children, 33% were found to have ocular abnormalities. The abnormalities were relatively minor, the most frequent being altered retinal pigmentation. Although congenital rubella infection was the most common cause of this finding the cause in others was more obscure. Possible causes for hearing loss associated with retinal pigment and other tissue changes are abnormal cilia, abnormalities in cells with similar embryological origins and genetic defects affecting pigmentation.