Vol. 99  No. July 2006

Schwannoma Arising from the Pharyngeal 
Branch of the Vagus Nerve

Akiko Katoh, Takeyuki Fujimura, Takashi Shimizu, Koich Hashida, 
Takuro Kitamura, Teruo Shiomori and Hideaki Suzuki
(University of Occupational and Environmental Health, School of Medicine)

      We report a rare case of schwannoma arising from the pharyngeal branch of the vagus nerve. An 18-year-old woman presented with an egg-sized nontender upper cervical swelling. Computed tomography and magnetic resonance imaging (MRI) revealed a well-defined tumor measuring 50 mm in its major axis in the left carotid space. The tumor was moderately enhanced, and showed hypointensity and isointensity on T1- and T2-weighted MRI, respectively. Otorhinolaryngological findings were otherwise normal. A schwannoma was most likely suspected, and she underwent transcervical resection of the tumor. A cord-like strand connected to the cephalad end of the tumor was severed, while both the vagus and hypoglossal nerves were identified and preserved. The histopathological diagnose is schwannoma. After surgery, the patient manifested a curtain sign toward the unaffected side without showing vocal cord palsy or Horner's syndrome, indicating that the tumor had arisen from the pharyngeal branch of the vagus nerve. Clinical characteristics of schwannomas in the carotid space were reviewed.

Key words:
schwannoma, pharyngeal branch, vagus nerve, carotid space, curtain sign

第99巻7号 目次   Vol.99 No.7 contents