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Longitudinal cavities in the spinal cord, most often in the cervical region, which may extend for multiple spinal levels. The cavities are lined by dense, gliogenous tissue and may be associated with SPINAL CORD NEOPLASMS; spinal cord traumatic injuries; and vascular malformations. Syringomyelia is marked clinically by pain and PARESTHESIA, muscular atrophy of the hands, and analgesia with thermoanesthesia of the hands and arms, but with the tactile sense preserved (sensory dissociation). Lower extremity spasticity and incontinence may also develop. (From Adams et al., Principles of Neurology, 6th ed, p1269)

A state of combined hydromyelia and syringomyelia, or a state in which cavities exist in the spinal cord, which are produced partly by distention of the central canal partly by disintegration of the tissue outside of the latter.

Distention of central canal of spinal cord, with formation of cavities and degeneration.

Dilatation of the central canal of the spinal cord by watery effusion, with the formation of cavities due to degeneration. [Gr.]