Homogeneous low density mass lesion is seen filling the entire right maxillary antrum. It protrudes through the widened maxillary antral ostium into the corresponding choana to reach the posterior nasopharynx.
1 study question available
Q: What are the differentials of antrochoanal polyp?
A: inverted papilloma, paranasal sinus mucocoele.
Antrochoanal polyp is a solitary sinonasal polyp arises from the maxillary antrum and passes through an enlarged ostium to protrude into nasal cavity and nasopharynx.