Giant slow flow vascular malformation of the posterior pharyngeal wall: a rare entity

Arteriovenous malformations (AVMs) involving the posterior pharyngeal wall are sporadic and pose significant clinical and surgical challenges due to their proximity to vital airway and vascular structures. We report a case of a large posterior pharyngeal AVM in a 52-year-old male, presenting with stertor, progressive dysphonia, dysphagia, and oropharyngeal swelling. Imaging revealed a non-infiltrative vascular lesion occupying the oropharynx and extending from the lower nasopharynx up to the valleculae level. The lesion was successfully excised via microscope-assisted intraoral surgery following elective tracheostomy. Postoperative follow-up showed complete recovery without recurrence. It is the largest size of slow-flowing AVM in the posterior pharyngeal wall reported in the English literature till date. This case underscores the importance of early recognition, imaging, and a multidisciplinary approach for managing complex vascular lesions of the upper aerodigestive tract (posterior pharyngeal wall).