Supratonsillar fossa

The supratonsillar fossa is a small mucosal recess located in the superior part of the tonsillar fossa, above the upper pole of the palatine tonsil. It lies between the palatoglossal arch anteriorly and the palatopharyngeal arch posteriorly and is formed because the palatine tonsil does not completely occupy the tonsillar fossa.

Anatomically, the supratonsillar fossa represents the superior extension of the tonsillar space and is often partially covered by the plica semilunaris, a crescent-shaped mucosal fold extending between the two arches.

Clinical correlate

Clinically, the supratonsillar fossa is important because it can retain desquamated epithelial cells, mucus, food debris, and bacteria. This predisposes the region to recurrent infection and chronic tonsillitis and may contribute to the formation of caseous material or tonsilloliths.