A NEW CLASSIFICATION OF THE RETINOSCHISES

Background: Two classifications of retinoschisis were published in the 1960s. A marked expansion of our knowledge of the diseases that give rise to retinoschisis indicates the need for an updated classification . Methods: The new classification is based on the authors' clinical ex perience, an extensive review of the literature, and a survey of 20 vi treoretinal specialists. Results: There are three types of retinoschis is: degenerative, hereditary, and secondary. Degenerative retinoschisi s is very common and has been published extensively. In addition to th e well known X-linked hereditary retinoschisis, there are less common pedigrees with autosomal recessive or autosomal dominant patterns. The re are at least 18 ocular diseases that may show varying degrees of se condary retinoschisis. Conclusion: The many types of retinoschisis are divided into these major categories. The multiplicity of types is emp hasized by the plural form of the term: ''the retinoschises.''