SYRINGOMYELIA IN ASSOCIATION WITH TUMORS OF THE POSTERIOR-FOSSA - PATHOPHYSIOLOGICAL CONSIDERATIONS, BASED ON OBSERVATIONS ON 3 RELATED CASES

In this report we describe 3 patients with syringomyelia in association with rumours of the posterior fossa. In each patient the syrinx was demonstrated on pre-operative magnetic resonance imaging (MRI). After total or partial removal of the tumour the syrinx collapsed. It is concluded that the pathogenesis of syrinx formation in this entity requires interference with normal cerebrospinal fluid (CSF) flow at the foramen magnum. We suggest that the obstruction to the flow of CSF causes alterations in the passage of extracellular fluid (ECF) in the spinal cord which lead to syringomyelia.