Injury to the external branch of the superior laryngeal nerve causes weakened phonation because the vocal cords cannot be tightened. Injury to one of the recurrent laryngeal nerves produces hoarseness, if both are damaged the voice may or may not be preserved, but breathing becomes difficult. Development
In newborn infants, the larynx is initially at the level of the C2–C3 vertebrae, and is further forward and higher relative to its position in the adult body. The larynx descends as the child grows. Laryngeal cavity
The laryngeal cavity (cavity of the larynx) extends from the laryngeal inlet downwards to the lower border of the cricoid cartilage where it is continuous with that of the trachea.It is divided into two parts by the projection of the vocal folds, between which is a narrow triangular opening, the rima glottidis. The portion of the cavity of the larynx above the vocal folds is called the laryngeal vestibule; it is wide and triangular in shape, its base or anterior wall presenting, however, about its center the backward projection of the tubercle of the epiglottis. It contains the vestibular folds, and between these and the vocal folds are the laryngeal ventricles. The portion below the vocal folds is called the infraglottic cavity. It is at first of an elliptical form, but lower down it widens out, assumes a circular form, and is continuous with the tube of the trachea. Function
Sound generation
Sound is generated in the larynx, and that is where pitch and volume are manipulated.
These are potential conflicts of interest that he has never disclosed when publishing scientific articles, which would be against ethical practices of some countries such as the United States. Media
CCSVI has received a great deal of attention in all media, the scientific literature and on the Internet. Moreover, the CCSVI case has been considered a good example of how new communication technologies and social media are modifying the traditional relationship between science, politics, medicine, and the general public. In this sense they have played a key role in effectively promoting the theory.Media coverage has been perceived by some as "hype", with exaggerated claims that have led to excessive expectations. This has been partially attributed to some of the investigators of the theory. Mainstream media initial approximations to Zambonis theory were enthusiastic and emphasized Zambonis effort to find a cure for his wife, along with the improvement of some patients after its alleged treatment. Initial difficulty reproducing results connecting MS and CCSVI, combined with reports of secondary effects of the surgical procedure, led to a more cautious discourse proposing that more investigation in the relationship between CCSVI and MS was needed. The first fatality related to CCSVI treatment was a pivotal development in this trend towards a less optimistic media view of the theory.The Internet has been extensively used by patient groups to obtain and disseminate information on CCSVI.