Describe the antrochoanal polyp.

Antrochoanal Polyp

• IT has three parts, and describing them is the clearest way to answer: an antral part (a cyst within the sinus), a narrow stalk passing through the ostium, and a nasal or choanal part.
• It occurs in children and young adults, and is commoner in males — which is itself a clue.
• The cause is uncertain; it is thought to arise from an antral mucous retention cyst that prolapses through the ostium, and it is not strongly associated with allergy, unlike ethmoidal polyps
• The cardinal features that distinguish it from ordinary polyposis:
• It is unilateral — whereas inflammatory polyps are bilateral
• It is solitary — whereas inflammatory polyps are multiple
• It grows backward toward the choana and nasopharynx, so it causes obstruction that is worse on expiration (a ball-valve effect) and may be visible behind the soft palate or cause bilateral obstruction when large
• It arises in a child or young adult
• Symptoms — unilateral nasal obstruction, nasal discharge, a nasal quality of voice, snoring, and occasionally a mass appearing in the oropharynx; and, if very large, dysphagia or sleep-disordered breathing
• Examination — a smooth, pale, greyish polyp in the nasal cavity, best seen on endoscopy, with posterior rhinoscopy or endoscopy showing the choanal component
• Imaging — CT shows opacification of the maxillary antrum continuous with a soft tissue mass extending through the ostium into the nose and choana, with widening of the ostium but NO bone destruction
• The absence of bone destruction is important, since it helps distinguish it from a neoplasm
• The differential — angiofibroma in an adolescent male.
• Treatment is complete surgical removal, and the whole point is that the antral origin must be removed
• Endoscopic removal with a middle meatal antrostomy, delivering the nasal and choanal part and then removing the antral portion and its attachment under vision, is the standard operation
• Simple avulsion of the nasal part alone leaves the antral origin and recurs — which is the classical error and the reason the anatomy is taught
• A caldwell-LUC approach was formerly used and is now reserved for difficult or recurrent cases, being avoided in children because of damage to unerupted tooth buds and to facial growth