Supraglottic phonation

Making voice by means of supraglottic vibration rather than glottic (true vocal cord) vibration. The supraglottic tissues used for vibration can vary between individuals. Vibrating tissue can be the false vocal cords (false cord phonation), aryepiglottic cords, or apical arytenoid mucosa.

Supraglottic phonation may become necessary if the vocal cords are absent or scarred to the point of being unable to vibrate. Examples might include larynx trauma, partial laryngectomy with loss of one or both vocal cords or an inability to bring them close enough together to be entrained into vibration, or progressive radiation damage (radiation fibrosis), usually many years after treatment for cancer.


Photos:


[Gallery not found]

False cord phonation

Making voice by vibrating the false vocal cords. This kind of phonation is unlike normal phonation or voice-making, which uses the true vocal cords.

False cord phonation produces a much deeper, rougher voice quality than normal phonation. It is purposefully used in certain kinds of vocal performance, such as Tibetan chant or heavy metal screaming. It can also occasionally serve as an alternate voice for a person whose true cords are unable to vibrate—due, for example, to their surgical removal or to scarring. It can also be produced concurrently with true cord phonation to produce a “Louis Armstrong” effect.


Photos:






Audio:

True cord phonation

False cord phonation

True and false cord phonation

Laryngeal vestibule

The “airspace” above the level of the vocal folds that is bounded by the posterior surface of the epiglottis, the medial surfaces of the aryepiglottic folds, and the anterior faces of the arytenoid cartilages.

Tracheoesophageal party wall

The membranous shared wall between the trachea and esophagus. The tracheoesophageal party wall is also known as the membranous trachea. This membranous wall makes up one-third of the trachea’s circumference; the other two-thirds is bolstered and stiffened by cartilaginous rings. These stiff cartilaginous rings help to keep the trachea open, whereas the membranous wall has some flexibility and may momentarily bulge into and narrow the tracheal passageway, as during a cough or a Valsalva maneuver.


Photos:



Posterior commissure

The flat, front-facing surface of the glottic aperture that lies between the vocal cord’ posterior ends. When the vocal cords are in abducted (breathing) position, the posterior commissure is at its widest, since the cord’ posterior ends are spread furthest apart from each other. When the vocal cords have come together into adducted (voicing) position, the posterior commissure is essentially just the point of contact between the posterior ends of the cords.

In individuals who have acid reflux or other inflammatory conditions, the mucosa at the posterior commissure may thicken (pachyderma).

See also: anterior commissure.

Anterior commissure

The point at which the vocal cords are joined together, which is at the most anterior end of each cord. Compare this with the posterior commissure.

Hypopharynx

The inferior-most part of the pharynx, made up of the pyriform sinuses, the lowest part of the posterior pharyngeal wall, and the post-arytenoid/post-cricoid areas.

Pyriform sinus

Pyriform sinus refers to the pear-shaped fossa (Latin for “trench”) just lateral to the laryngeal entrance. Its medial surface is the aryepiglottic cord; laterally it is bounded by the thyroid cartilage, and posteriorly by the low posterior pharyngeal wall. The pyriform fossas and post-arytenoid area together constitute the “swallowing crescent,” which channels swallowed material just before it enters the esophagus, behind the larynx.

Vocal process

A projection of the anterior arytenoid cartilage, to which is attached the membranous vocal cord.


Photos: