Medullary cavities associated with tumors of the spinal cord were reported by early pathologists and anatomists such as Etienne (1546), Brunner (1688) and Morgagni (1740).1 It was not until 1824, however, that the term "syringomyelia" was introduced by Ollivier.2 He thought that the mere presence of a patent central canal was evidence of an abnormal condition. At that time it was commonly believed that normally the central canal became extinct during the latter part of fetal life. In 1859, Stilling3 was the first to establish definitely that the central canal is normally present, but he also believed that syringomyelia is always the result of dilatation of the central canal.
Because of different pathologic changes considerable interest and discussion arose as to the cause of syringomyelic cavities, and many theories were advanced in the latter part of the nineteenth century. It was later pointed out by Hoffmann,4