 This sinus is a common place for food particles to become trapped; if foreign material becomes lodged in the piriform fossa of an infant, it may be retrieved nonsurgically.If the area is injured (e.g., by a fish bone), it can give the sensation of food stuck in the subject's throat.Remnants of the pharyngeal pouches III and IV may extent to the piriform sinus as sinus tracts which are sometimes imprecisely called "fistulas".