Hydrocephalus, Syringomyelia, and Spinal Cord Angiodysgenesis in a Lhasa-apso Dog

Abnormal cavitations of the central nervous system gen-erally are named by using the idiom “syrinx- ” and they occur most frequently in the spinal cord as syringomyelia. The underlying event usually is a malformation of the central nervous system caused by arrested development before gray and white matter have completed differentiation. ’ Acquired syringomyelia as a post-traumatic event also has been de-scribed in man.15 Syrinx formation in man also may be caused by hydrodynamic disorders of the cerebrospinal fluid where pulsations of the fluid lead to abnormal distension and dis-ruption of the spinal canal. Circulation disorders within the spinal cord are another important cause of syrinx forma-tion. ’ We describe syringomyelia in a Lhasa-apso dog associ-ated with a developmental disorder of both the central nervous system and the spinal blood vessels. While the former status