External branch of superior laryngeal nerve supply:
Right recurrent laryngeal nerve may be superﬁcial or deep to the inferior thyroid artery.
Occasionally, some branches are superﬁcial & some are deep.
Left recurrent laryngeal nerve is usually deep to inferior thyroid artery.
Cricothyroid
Thyroarytenoid
Posterior cricoarytenoid
Cricoarytenoid