The Anatomy of the Larynx, Pharynx and Cervical Oesophagus in Relation to Surgical Voice Restoration

Abstract

Any anatomical study of the remaining pharynx and oesophagus after laryngectomy must consider innervation and muscle fibre course. One hitherto unsolved problem is the simultaneous arrival of nerve impulses in the vocalis, pharynx and oesophagus muscles from the left and right. It is known that the left recurrent laryngeal nerve has to cover a longer distance than the right one. This is why the course of the nerve fibres from their nuclei to their effector organs needs to be briefly described. The motoric fibres of the vagus nerve emerge from the large-cell nucleus which is approximately 20 mm long and 3 mm thick. It stretches cranially from the region of the medullary stria and caudad until the decussation of the pyramids (Kirsch et al. 1968). The nucleus is approximately 4 mm below the floor of the fourth ventricle in cranial areas and about 6 mm deep in caudal areas. It is sited ventrally and somewhat laterally to the gracile nucleus. Fibres for the palatine and pharyngeal muscles go from a small rostral area into the glossopharyngeal and vagus nerves. Fibres for the larynx muscle go from the larger caudal section into nerve X. Fibres for the superior laryngeal nerve come from the rostral part of the laryngeal segment. Those for the cricoarytenoid muscles emerge from a somewhat more caudal area. Fibres for the arytenoid muscles emerge from an area placed even farther caudally (Kirsch 1968).

This work is dedicated to my colleague and dear friend Professor Dr. med. Walter Kley, head of the Department of Otolaryngology, University of Würzburg, on his 65th birthday.