Unilateral polyp arising from right antral mucosa surface (+), enlarging slowly, and finally extrude into middle meatus via accessory meatus (arrow). [MT - middle meatus, S - nasal septum]
Transnasal nasopharyngoscopy using 70 rigid endoscope (facing upward) showing the choanal segment of an established antrochoanal polyp (P). (R - right, L - left, TT - torus tubarius, arrow - fossa of Rosenmüller, # - roof of nasopharynx)
Figure 1 Figure 2
Figure 3 Figure 4
Antrochoanal polyp means a polyp arising from the antral mucosa and extending into the posterior choana (dumb bell-shaped) after its exit usually through the accessory ostium.
Figure 1: origin and attachment of polyp from antral mucosa.
Figure 2: polyp after its exits from left maxillary accessory ostium
Figure 3: posterior extension of polyp into the postnasal space as seen through right nasal cavity
Figure 4: occasionally, longstanding polyp can be seen behind the soft palate or even in the oropharynx
CT-scan usually shows an opacified maxillary sinus on the affected side with soft tissue opacity extending into the nasopharynx.
Watch video of antrochoanal polyp @ YouTube