Maxillary sinonasal polyposis

Clinical presentation

35 year old lady with chronic left sided headache



Polypoidal soft tissue lesion is seen completely opacifying left maxillary sinus resulting in a wide open sinus ostium with soft tissue extending to nasal cavity obscuring middle meatus. Non visualization of middle turbinate. There is associated diffuse left ethmoidal mucosal thickening with rarefaction of ethmoid labyrinth. Mild mucosal thickening in left frontal sinus. No posterior choanal extension of nasal polyp. Nasopharynx is free.


Most common expansile soft tissue lesion in maxillary sinus dilating the ostium and extending into the nasal cavity is a large sinonasal polyp. As it grows there is rarefaction of the walls of the sinus due to expansion and polyps extend into the nasal cavity. When seen to encroach posteriorly beyond the posterior choana, we term it an antrochoanal polyp. The increased central density of the polyp shows its chronic nature and also raised suspicion of underlying fungal etiology.

Read more

  1. Broderick, Daniel F. “The opacified paranasal sinus: Approach and differential.” APPLIED RADIOLOGY (2015).
  2. Radiopaedia – sinonasal polyposis