RT Book, Section A1 Douglas, Vanja C. A1 Aminoff, Michael J. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. A2 McQuaid, Kenneth R. SR Print(0) ID 1184184986 T1 Syringomyelia T2 Current Medical Diagnosis & Treatment 2022 YR 2022 FD 2022 PB McGraw-Hill Education PP New York, NY SN 9781264269389 LK accessmedicine.mhmedical.com/content.aspx?aid=1184184986 RD 2024/03/28 AB Destruction or degeneration of gray and white matter adjacent to the central canal of the cervical spinal cord leads to cavitation and accumulation of fluid within the spinal cord. The precise pathogenesis is unclear, but many cases are associated with Arnold-Chiari malformation, in which there is displacement of the cerebellar tonsils, medulla, and fourth ventricle into the spinal canal, sometimes with accompanying meningomyelocele. In such circumstances, the cord cavity connects with and may merely represent a dilated central canal. In other cases, the cause of cavitation is less clear. There is a characteristic clinical picture, with segmental atrophy, areflexia, and loss of pain and temperature appreciation in a “cape” distribution, owing to the destruction of fibers crossing in front of the central canal (eFigure 24–17) in the mid-cervical spinal cord. Thoracic kyphoscoliosis is usually present. With progression, involvement of the long motor and sensory tracts occurs as well, so that a pyramidal and sensory deficit develops in the legs. Upward extension of the cavitation (syringobulbia) leads to dysfunction of the lower brainstem and thus to bulbar palsy, nystagmus, and sensory impairment over one or both sides of the face.