Schwannoma of the intrasternomastoid portion of the spinal accessory nerve: sophisticated preoperative CT diagnosis and appropriate surgical management.

Neurogenic tumors of the cervical portion of the cranial nerves are rare, and hence frequently misdiagnosed and mismanaged. A unique case of an isolated schwannoma of the spinal accessory nerve was correctly diagnosed by the constellation of signs demonstrated on a CT examination. This led to appropriate surgical removal with full motor nerve preservation. The primary purpose of this manuscript is to demonstrate the qualitative and quantitative radiologic signs indicative of the diagnosis and the surgical management resulting therefrom. The second more subtle purpose is to demonstrate the sophisticated clinical implications which can result from effective high-technology imaging.