Acute and atypical presentations of syringomyelia.

Syringomyelia is characterized by a longitudinal cavity or several cavities in the spinal cord, and syringobulbia demonstrates similar pathology in the brainstem. Both conditions typically present with slowly progressing dissociative sensory deficits as well as upper and lower motor neuron deficits. We recently encountered 3 patients who presented with the rapid onset of such signs and symptoms and had cervical syringes. All 3 patients would have been diagnostic dilemmas had it not been for MRI, which identified a syrinx in each patient, as well as an Arnold-Chiari malformation in 2 of the 3. Syringomyelia and syringobulbia should be considered in the differential diagnosis of patients who have acutely evolving brainstem or cervical spinal cord deficits. MRI is the imaging modality of choice for detecting syringomyelia or syringobulbia presenting atypically.