It is a deep recess broad above and narrow below in the anterior part of lateral wall of the laryngopharynx on each side of the laryngeal inlet.... It is sometimes artificially deepened by smugglers using lead balls to hide precious materials like diamonds..For this reason piriform fossa is also called as Smugglers fossa The ingested foreign bodies like pins or fish bones are sometimes lodged into the piriform fossa.If care is not taken the removal of foreign bodies may damage the internal laryngeal nerve leading to anesthesia in the supraglottic part of the larynx and subsequent loss of protective cough reflex....