Tumors of the parapharyngeal space are often encountered in the suprahyoid neck. The most common tumors in this space are pleomorphic adenomas, tumors of neurogenic origin, and paragangliomas, and they usually do not pose a diagnostic dilemma. Therefore, tissue diagnosis is seldom required. However, certain rare varieties of tumors of the parapharyngeal space may represent a diagnostic challenge and thus may hinder surgical planning. Conventionally, the parapharyngeal space is divided into prestyloid and poststyloid compartments. The tumors that are found in the prestyloid compartment are pleomorphic adenomas, which arise in the deep lobe of the parotid gland or in the salivary gland rests and displace the carotid sheath posteriorly. Paragangliomas and neurogenic tumors arise in the poststyloid compartment. Paragangliomas displace the carotid sheath anteriorly, and MRI may demonstrate typical flow voids or a “salt-and-pepper” appearance on T2-weighted sequences, with striking early postcontrast enhancement on dynamic CT scans or MRIs. Glomus tumors may also produce permeative lytic erosions in the region of the jugular foramen.
Radiology Quiz Case 1: Diagnosis. Arch Otolaryngol Head Neck Surg. 2009;135(10):1052-1055. doi:10.1001/archoto.2009.127-b