CT - Neck
A 3.0 x 3.0 x 2.7 cm low attenuation mass is present within the deep lobe of the left parotid gland showing faint to moderate central irregular curvilinear and minor rim enhancement. It medially abuts the carotid artery, oropharyngeal muscles and effaces the parapharyngeal fat. It posteriorly contacts the jugular vein with no evidence of venous thrombosis.
The lesion laterally abuts the left mandibular ramus and there is evidence of pressure erosion of the mid-portion of posterior aspect of the medial cortical bone. Likely enlarging but not eroding the orifice of mandibular canal of the inferior alveolar nerve. The mass is epicentred between the medial and lateral pterygoid muscles. No skull base contact skull. No cervical nodal disease. The appearances are typical of a long-standing salivary gland pleomorphic adenoma.
Conclusion:
Left deep parotid space / parapharyngeal mass, compressing but not invading adjacent structures. Differentials include benign and malignant salivary gland /parapharyngeal tumours.