Cervical Spinal Cord Neoplasm in a Patient with an Implanted Cervical Spinal Cord Stimulator: The Controversial Role of Magnetic Resonance Imaging

Abstract

To discuss the diagnostic relevance and safety concerns of performing magnetic resonance imaging (MRI) in the presence of an implanted spinal cord stimulator (SCS). A 39-year old man with CRPS I and major depression fell and fractured his humerus. A cervical SCS had been placed several years earlier. After the fall, he developed progressive lower extremity weakness. Eventually, he became wheelchair dependent and required assistance with transfers. These symptoms were attributed to CRPS and deconditioning. He was admitted to an inpatient rehabilitation unit for functional restoration. At presentation, he reported developing neck and upper thoracic pain, which started several months before the fall - a pain that was distinct from his total body pain. A contrast-enhanced CT scan of the neck was normal, except for the spinal cord stimulator induced artifact. Our pain service was consulted. After performing a neurological exam, cervical myelopathy was suspected. An MRI of the spine demonstrated a mass compressing the cervical spinal cord. The patient tolerated the MRI, despite the presence of a neurostimulator. The mass was identified as an extramedullary, intradural schwannoma and was completely excised during surgery. The patient made a profound neurological recovery. The diagnostic value of MRI may outweigh the potential dangers of using this imaging modality when a patient with a neurostimulation device presents with a new-onset neurological deficit. Thorough informed consent and close physician monitoring of these patients during the MRI is imperative.