Case Report: Absent F-Waves in a Case of Spinal Ischemia - A Potential Source of Diagnostic Error

Rapidly progressive para- or tetraparesis and early loss of F-waves on electrodiagnostic studies usually indicate acute inflammatory demyelinating polyneuropathy. A less common alternative etiology is acute spinal cord pathology.

We describe here a case of a 65-year-old woman with progressive motor deficits and absent F-waves early in the disease course due to anterior spinal artery syndrome. We provide serial electrodiagnostic findings with a focus on the basic electrodiagnostic parameters as well as imaging correlates during the inpatient management.

Anterior spinal artery syndrome represents an uncommon cause of absent F-waves on the electrodiagnostic exam. Absent F-waves may precede any changes on the imaging and follow-up investigations are often warranted, as spinal cord ischemia can be a dynamic process.