See hydromyeliaMeaning “water within the spinal cord”, this word is synonymous with syringomyelia, although some authorities do make a distinction between the two terms. Some say that hydromyelia describes a state where the embryonic central canal persists or re-expands. The word syringomyelia is then reserved for fluids accumulating inside the spinal cord, other than within the central canal. In order to cover both definitions, some specialists in the field use the term syringohydromyelia. More.