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Asymmetric Pterygoid Venous Plexus Mimicking a Neck Mass
A patient with an incidental neck mass on MRI is found to have an asymmetric pterygoid venous plexus, a normal variant.
Imaging overview:
Axial T2 fat-suppressed MRI shows a round, hyperintense structure in the left parapharyngeal and pterygoid region. Post-contrast fat-suppressed T1 shows uniform enhancement of the same structure. Its signal and enhancement match the other veins of the pterygoid plexus, and its round appearance reflects a vessel in cross-section.
Clinical insight:
The pterygoid venous plexus is a deep facial venous network in the parapharyngeal and masticator spaces, and it drains the cavernous sinus. Asymmetry is common and is usually incidental and asymptomatic. Look for serpiginous T2 hyperintense signal and uniform enhancement that matches other veins. Recognizing this pattern prevents unnecessary biopsy or further workup of a benign finding, and clinical history helps confirm that no true lesion is present.
Case courtesy of Kalen Riley, MD, MBA, Indiana University School of Medicine.