A Rare Case of Parapharyngeal Venous Malformation: Diagnostic and Management Challenges

Background: Venous malformations previously referred to as cavernous haemangiomas, are slow-flow vascular anomalies characterised by a benign clinical progression. The occurrence of parapharyngeal space as the primary site of a venous malformations is exceptionally rare, with our literature review indicating that just over 20 cases have been documented to date. The diagnosis of a venous malformation in the parapharyngeal space can be difficult, as they clinically mimic more prevalent lesions in the area, such as pleomorphic adenomas and other neurogenic tumours. Case presentation: We report a case of the most extensive venous malformations of the parapharyngeal space ever recorded, which was accompanied by the longest duration of symptoms in a 38-year-old male who presented with a painless neck swelling. The swelling was insidious in its onset and had progressively increased to its current dimensions of approximately 8 x 5 cm over a span of 20 years. On examination, there was a solitary diffuse enlargement in the upper lateral aspect of the right neck, accompanied by transmitted pulsations. Cytology was inconclusive, yielding a bloody aspirate only. Contrast-enhanced magnetic resonance imaging revealed a T1 iso- to mildly hyperintense, T2/STIR hyperintense lesion measuring 5.2 x 5.8 x 8.0 cm in the right carotid space displacing the carotid sheath laterally with few flow voids and heterogeneous enhancement post-contrast. The mass was excised through a transcervical approach. A reddish, lobulated, encapsulated mass was removed in its entirety during the operation. Histopathology revealed that the mass was a venous malformation, characterised by thin-walled vessels, extensive hyalinization, and fibrin. Conclusion: The diagnosis of venous malformation is primarily determined by the clinical features and the MRI findings. Surgery is the preferred treatment, and the surgical approach should be determined by the tumour’s size, location, and anatomical accessibility.