Glomus vagale tumors are paragangliomas that occur along the path of the vagus nerve (CN X). They are a subset of extra-adrenal neuroendocrine tumors that are derived from the nonchromaffin paraganglion cells.
Typically presents as a painless mass behind the carotid artery. Vocal cord paralysis is a relatively frequent finding (~47%) 3.
For a general discussion on the pathology for these tumors, please refer to the parental article on paragangliomas.
Although they could occur at a similar position to carotid body tumors they tend to be more rostral in location and do not widen the carotid bifurcation. They displace the internal and external carotid arteries anteriorly, and the internal jugular vein posteriorly 1.
Difficult to sonographically differentiate between other lesions that can potentially occur in this location. May be seen as a solid heterogeneously hypoechoic lesion comprising of small vascular structures 3.
- T1: usually low signal
- T2: high signal with multiple flow voids, which may give a salt and pepper appearance
- T1C+: intense enhancement
The differential for lesions in this location include 2,4:
- 1. Weissman JL. Case 21: glomus vagale tumor. Radiology. 2000;215 (1): 237-42. doi:10.1148/radiology.215.1.r00ap52237 - Pubmed citation
- 2. Kehagias DT, Bourekas EC, Christoforidis GA. Schwannoma of the vagus nerve. AJR Am J Roentgenol. 2001;177 (3): 720-1. doi:10.2214/ajr.177.3.1770720 - Pubmed citation
- 3. Giovagnorio F, Martinoli C. Sonography of the cervical vagus nerve: normal appearance and abnormal findings. AJR Am J Roentgenol. 2001;176 (3): 745-9. doi:10.2214/ajr.176.3.1760745 - Pubmed citation
- 4. Harnsberger HR, Glastonbury CM, Michel MA et-al. Diagnostic Imaging: Head and Neck. Lippincott Williams & Wilkins. (2010) ISBN:1931884781. Read it at Google Books - Find it at Amazon