Table 1:

Derivatives of the BAs

FirstExternal ear canalMandible, muscles of mastication, 5th cranial nerve, malleus, and incusTrigeminal nerve (V2 and V3)Eustachian tube, tympanic cavity, mastoid air cells
SecondCervical sinus of HisMuscles of facial expression, body and lesser horns of hyoid, 7th and 8th cranial nerves, stapesFacial nerve (VII)Palatine tonsil
ThirdCervical sinus of HisSuperior constrictor muscles, internal carotid artery, 9th cranial nerve, greater horn, and body of hyoidGlossopharyngeal nerve (IX)Inferior parathyroid, thymus, pyriform fossa
FourthCervical sinus of HisThyroid and cuneiform cartilages, 10th cranial nerve, aortic arch and right subclavian artery, part of laryngeal musclesVagus nerve (X), superior laryngeal nerveSuperior parathyroid, apex of pyriform sinus
Fifth and sixthNonePortions of the laryngeal muscles and skeleton, inferior pharyngeal constrictor muscles, 11th cranial nerveVagus nerve (X), recurrent laryngeal nerveParafollicular ″C″ cells of thyroid gland