piriform fossa

pir·i·form fos·sa

[TA]
a recess in the anterolateral wall of the nasopharynx on each side of the vestible of the larynx separated from it by the aryepiglottic folds.

pir·i·form fos·sa

(piri-fōrm fosă) [TA]
Recess in anterolateral wall of nasopharynx on each side of vestibule of the larynx separated from it by aryepiglottic folds.
References in periodicals archive ?
The most common sites of fish bone impaction are the tonsils, tonsillar pillars, tongue base, valleculae, and piriform fossa.
This demonstrated that the large pedunculated necrotic mass was in fact, appearing to arise from the right piriform fossa and not the tonsil confirmed by rigid pharyngolaryngo-upper oesophagoscopy.
Further imaging demonstrated a remnant of the base of the lesion low in the piriform fossa possibly going up to the upper oesophagus and a barium swallow revealed some oesophageal mucosal irregularity at approximately 21cm.
Further flexible nasoendoscopy assessment in clinic was concerning and unhelpful in assessing the piriform fossa (right side--erythematous and oedematous), prompting a further general anaesthetic rigid laryngopharyngo-upper oesophagoscopy procedure to exclude a synchronous tumour.
On flexible laryngoscopy, a small left pharyngocele was seen at the thyrohyoid membrane just above the thyroid cartilage and piriform fossa (figure, A).
Intraluminally, this area is located in the area of the base of the piriform fossa.
5) Foreign bodies can become lodged in the tonsil, base of the tongue, piriform fossa, and cervical esophagus.
The entire sac was excised, and the apex of the piriform fossa was found to be normal.
Examination revealed the presence of a pedunculated mucosal lesion on the posterior pharyngeal wall; the mass was situated to the left of the midline and just above the piriform fossa.
1) Incomplete obliteration of these ducts, however, results to a vestigial sinus of the piriform fossa.