Diseases of the nose, throat and ear, medical and surgical
William Lincoln Ballenger
Paperback
(RareBooksClub.com, May 22, 2012)
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1909 Excerpt: ...or vagus nerves. It will be remembered that these nerves have their origin near the median furrow beneath the floor of the fourth ventricle. Two motor branches, the superior laryngeal and the recurrent or inferior laryngeal, are given off from each vagus to the larynx. The superior laryngeal also supplies sensation to the whole laryngeal mucous membrane. By reference to Fig. 307 it will be seen that the superior laryngeal supplies only one pair of the intrinsic muscles of the larynx, the cricothyroidei. These muscles are tensors of the vocal cords, hence the wavy outline of the cords (Fig. 308) in superior laryngeal paralysis. Flo 307 Schema of the nerve supply of the intrinsic muscles of the larynx. P. the pneumogastric nerve; R, recurrent laryngeal nerve; S.L., superior laryngeal nerve; A.C., arytenoid cartilages; T, thyroid cartilage; C, cricoid cartilage; A, interarytenoideus muscle; C.A.P., crico-arytenoideus posticus muscle; C.A.L., crico-arytenoideus lateralis muscle; T.A.I., cricothyroids interni muscles. The recurrent or inferior laryngeal nerves supply all the other intrinsic muscles of the larynx, namely, the arytenoideus, the crico-arytenoidei postici, the crico-arytenoidei laterales, and the internal tensors of the vocal cords. If the lesion involves all the fibers of the left recurrent laryngeal nerve, there is total paralysis of all the muscles of the left side of the larynx Fig. 308 except the cricothyroideus (external tensor). The same is true of the right side (Fig. 308). If the lesion involves only a small branch of the left recurrent, one muscle alone may be involved, say the crico-arytenoideus posticus. This muscle is an adductor, hence there would be inmplete adduction of the anterior two-thirds of the vocal cord on the left side, whil...