eRadiograph Volume 7: Imaging of Oral Cavity | Page 149

Primary pathologies of parapharyngeal spaces are:
Infections - cellulitis/abscess
Benign masses - benign mixed salivary gland tumors, venous, lymphatic, mixed
venolymphatic malformations, rarely atypical branchial cleft cyst, haemangiomas
lipomas asymmetric pterygoid venous plexus.
Malignant - minor salivary gland tumour, rarely liposarcomas.
Diseases from contagious spaces extending into PPS such as deep lobe parotid masses.
Pathologic processes of pharyngeal mucosal space:
Minor salivary gland tumors
These arise from salivary gland tissue rests in the parapharyngeal space. The most
common being pleomorphic adenoma. On imaging they appear as round to oval well
circumscribed mass lesions hypointense on T1W1, hyper-intense on T2W1, on contrast
administration reveal patchy heterogeneous enhancement.

On imaging this appears as a cystic mass projecting cephalad from the level of the
palatine tonsil in the parapharyngeal space extending to the skull base. A fat plane is
seen between the cephalad extension of the mass and the skull base. The contents are
homogenous of fluid intensity. On T1W1 the contents may be hyperintense due to
proteinaceous fluid.
Asymmetric ptyergoid venous plexus
The pterygoid venous plexus can be asymmetric and appear as a vascular mass. This is
seen as a homogenously enhancing area along the medial border of the lateral
ptyergoid muscle. The importance of diagnosing this as a pseudomass is important to
avoid an inadvertent biopsy.

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Parapharyngeal Space

Atypical 2nd Brachial cleft cyst
Second branchial cleft cysts are typically an FW&