Tumors of the parapharyngeal space and upper neck: MR imaging characteristics.

Abstract

Magnetic resonance (MR) imaging characteristics of 40 tumors involving the parapharyngeal space and the upper part of the neck were reviewed. These lesions could be classified as being either hypervascular (glomus tumors or metastatic kidney, thyroid, or venous hemangiomas) or hypovascular (salivary gland tumors, neurogenic tumors, lymphomas, sarcomas). Detailed analysis of the contour of the neoplasm combined with clinical findings allowed further refinement of the differential diagnosis in each category. Most lesions had an intermediate signal intensity on T1-weighted images and a fairly high signal intensity on T2-weighted images. Hypervascular tumors had a number of "channel voids" caused by high-flow vessels on T1- and T2-weighted images, and on T2-weighted images there were areas of high signal intensity, presumably due to sites of slow flow within the image plane. The hypovascular lesions were quite homogeneous, and it was therefore more difficult to differentiate among the neoplasms in this group.

Three Cases of Vagal Nerve Schwannoma and Review of Literature

“…On CT images, vagal schwannomas appear as well-defined masses, usually of higher attenuation than muscle on contrast-enhanced images. MR evaluation typically shows masses of intermediate signal on T1-weighted images and increased signal intensity on T2-weighted images with smooth, well-delineated margins and a homogeneous overall appearance [4]. Occasionally, as in our case 2, necrosis and cystic degeneration are seen.…”

Ossifying lipoma of the parapharyngeal space: CT and MRI findings

“…The most frequent lesions of the parapharyngeal space are deep-lobe parotid masses, minor salivary gland lesions, neuromas, and glomus tumors [12,13]. When a mass of the prestyloid compartment of the parapharyngeal space is demonstrated (posterior displacement of the internal carotid artery) and a primary salivary gland tumor is excluded (presence of a fat plane between mass and parotid gland), minor salivary gland lesion is the most frequent diagnosis [12].…”

“…Focal areas of low signal intensity may be due to either dystrophic calcifications or regions of fibrosis. Areas of irregular necrosis and calcifications are better evaluated by CT scans [12,13].…”

“…Differential diagnosis of the parapharyngeal masses also includes pathological lymph nodes, branchial cleft cysts, lipomatous lesions, and a few other rare tumors [12,13].…”

Management of parapharyngeal minor salivary neoplasms in children: A case report and review

“…Of prime importance in evaluating lesions of the PPS is the presence of a fat plane between the lesion and the deep lobe of the parotid [9]. This finding is important as many solid neoplasms of the PPS have similar imaging characteristics of intermediate intensity on T1 and high intensity on T2 images (as in our case) including salivary, lymphoma and neurogenic tumors [9]. In our case, a well defined fat plane at each cut is noted, thus representing a discreet lesion.…”