The term syringomyelia refers to any cavity within the substance of the spinal cord which may or may not communicate with the central canal (cavity wall is not lined by ependyma). The term hydromyelia refers to dilatation of the persistent central canal of the spinal cord which communicates with the fourth ventricle (cavity wall is lined by ependyma). The cavity in both lesions contains cerebrospinal-like fluid. The differentiation between hydromyelia and syringomyelia is at times difficult to make by radiological, clinical or pathological methods; therefore, the combined term, syringohydromyelia (or<unk> , can be used to avoid confusion.
Hydrosyringomyelia
Syringomyelia
Diastematomyelia
Adrenomyeloneuropathy
Amyotrophic lateral sclerosis
Transverse myelitis
Tethered spinal cord syndrome
Spinal cord tumor