Hydromyelia associated with spinal lipoma of the conus: case report.

Study Design: A case report and literature review of the treatment of "noncommunicating" syringomyelia. OBJECTIVE.: The aim of this report is to document the timing and the treatment of hydromyelia holocord after surgical treatment for both tethering and retethering of spinal lipoma.

Summary Of Background Data: Syringomyelia associated with spinal lipoma presents a different pathogenesis and treatment in comparison to the "communicating" hydromyelia in the myelomeningocele. After the primary retethering operation performed in symptomatic patients, recurrent retethering can occur with an increase of the syringomyelia signs and symptoms.

Methods: Syringomyelia treated with a thin silastic tube passed from the syrinx to the subarachnoidal space for drainage and decompression. Prior operations were: (1) initial untethering at birth, (2) second untethering at 5 years of age, (3) posterior fossa and cervical decompression.

Results: Magnetic resonance imaging 6 months post shunt operation demonstrated decompression of the hydromyelia holocord and syringobulbia with improvement of motor function of the legs and improvement in sensory symptoms.

Conclusion: Usefulness of syrinx-subarachnoidal shunt is demonstrated in this case report after unsuccessful decompression and detethering. When the enlargement of the ependymal channel is greater than 50% of the spinal cord's diameter, neurologic, and urological symptoms are evident and the patient benefitted from cord untethering and syrinx drainage. (1) The terminal "noncommunicating" syringomyelia in lumbar sacral lipoma has been reported to be associated with retethering in spinal lipoma in the 25% of the cases. (2) The rise of distal syringomyelia isn't only linked to the kind of the spinal lipoma, but also to the difficulty to obtain the untethering and a smooth cerebrospinal fluid flow between the subarachnoidal space and the ependymal canal. (3) In patients with hydromyelia holocord greater than the 50% of the spinal cord's diameter a myelotomy and insert an ependymal channel/syrinx to the subarachnoidal space shunt can resolve of the syrinx. In this case, the enlargement of the ependymal channel in "noncommunicating" syringomyelia associated with lumbosacral lipoma is greater than 50% of the spinal cord's diameter; neurologic and urological symptoms occurred and the patient benefited from cord untethering and concurrent syrinx drainage.