100 TOPOGRAPHICAL ANATOMY OF THE 



Dissection. — Release the lateral crico-arvtenoid imisclc fioin its cricoid 

 attachment in order that an uninterrupted view of the vocal muscle may 

 be obtained. 



M. VOCALIS : M. VENTRICULARIS. — Because of their intimate con- 

 nection at their origin and insertion, these two muscles are better 

 studied together. Their middle parts are separated by the intrusion 

 of the appendix of the ventricle of the larynx. They have a blended 

 origin from the ventral border of the thyroid lamina near the laryn- 

 geal prominence and from the adjacent part of the crico - thyroid 

 ligament. Their insertion is partly into the neighbourhood of the 

 muscular process of the arytenoid cartilage ; but some fibres (the 

 more superficial) are continued towards the middle line and blend 

 with the transverse arytenoid muscle. The superficial fibres are 

 often not strictly speaking part of the main muscular mass, but 

 arise independently by a thin aponeurosis from within the thyroid 

 lamina close to its dorsal border. 



Dissection. — Remove the vocal muscle. 



The Vocal and Ventricular Ligaments. — Immediately within the 

 vocal muscle is a thin membrane connected with the cranial border 

 of the arch of the cricoid cartilage, ventrally continuous with 

 the crico-thyroid ligament, and dorsally attached to the vocal 

 process of the arytenoid cartilage. The cranial edge of the 

 membrane blends with the vocal ligament (ligamentum vocale), 

 a definite and elastic band stretching from the laryngeal prominence 

 and crico-thyroid ligament to the vocal process of the arytenoid 

 cartilage. Each vocal ligament is covered by one of the vocal folds 

 of mucous membrane already examined in connection with the interior 

 of the larynx ; and, like the folds, the ligaments are close together 

 at their ventral ends, but diverge towards their arytenoid attach- 

 ments. 



The ventricular ligament (ligamentum ventriculare) is an ill- 

 defined band of fibres, covered by the ventricular fold of mucous 

 membrane, extending from the cuneiform cartilage to the vocal 

 process of the arytenoid. 



The Laryngeal Ventricle and its Appendix. — The ventricle (lateral) 

 of the larynx is an elongated depression, the anterior boundary of 

 which is mainly formed by the cuneiform cartilage and completed dorsally 

 by the ventricular fold. The posterior boundary of the ventricle is 

 formed by the vocal fold. 



The appendix of the ventricle is a spacious blind diverticulum 

 covered laterally by the lamina of the thyroid cartilage. Anteriorly 



