On the use of the epiglottis / by R. Beveridge.

  • Beveridge, R. (Robert)
Date:
[between 1850 and 1859?]
Catalogue details

Licence: Public Domain Mark

Credit: On the use of the epiglottis / by R. Beveridge. Source: Wellcome Collection.

    4/8 (page 4)
    with the folds in question to have any effect in keepi»g them asunder, and thus maintaining the opening between them patent. This effect seems to be produced solely by the epiglottis, wdiich, by its vertical position and its great elasticity, not only keeps perman¬ ently asunder the anterior ends of the folds, but also keeps them constantly tight, and that too whatever may be the position of the larynx in the neck. It might at first sight be supposed that such an effect could be as well produced by the connection of the two folds with the side of the base of the tongue without the intervention of such a body as the epiglottis, and so it would if the larynx had been either motionless or moveable only along with the tongue ; but. the larynx admits of a very considerable amount of motion in the neck as a means of modifying the note of the voice, and bnt for the presence of the epiglottis, the raising of the larynx would have slackened the two folds so much as to have allowed them to fall together, and so close the opening. The attachment, however, of the epiglottis by its narrow pointed lower extremity to the angle of the thyroid cartilage, causes it to move upwards and downwards along with the larynx, and in this manner the folds forming the lateral boundary of the superior opening of the larynx are kept permanently tense, and the constant patency of that opening is secured. But why should the epiglottis be formed of fibro-cartilage instead of cartilage as are the other pieces of the larynx ? or, in other words, why does it require to be more flexible than the rest of the larynx ? The answer to this involves the consideration of its function with regard to deglutition. The epiglottis is itself of a triangular or leaf-like form, having its broad upper end immediately behind the tongue. This upper end is rounded, the central portion of it being free, while the sides have attached the aryteno-epiglottis folds. Immediately below this, the epiglottis is placed in the hollow or curve formed by the hyoid bone to the bod}^ of which it is attached by elastic tissue; and narrowing rapidly below this is connected by its lower end with the retiring angle of the thyroid cartilage. Its position is thus vertical, and so long as it remains so it will keep tense the aryteno-epiglottic folds. This vertical position is in no ways affected