The glottis is a structure within the human throat involved in several bodily processes. It is not a standalone organ but part of the voice box, known as the larynx. This area enables communication through speech and song, facilitates breathing, and safeguards airways.
Where the Glottis Is Located
The glottis is situated within the larynx, located in the middle region of the neck. This structure rests behind the Adam’s apple, positioned between the upper part of the larynx (supraglottis) and the lower part (subglottis).
The glottis itself comprises two components: the vocal folds (also known as vocal cords) and the opening between them, referred to as the rima glottidis. These vocal folds are muscular bands of tissue that stretch across the larynx. The rima glottidis is the narrow, triangular opening that changes shape, allowing air to pass through.
How the Glottis Works
The glottis performs several roles, involving the coordinated movement of the vocal folds to regulate airflow. One function is voice production, or phonation. When we speak or sing, the vocal folds come together, and air exhaled from the lungs is forced between them, causing them to vibrate. This vibration creates sound waves, and the tension, length, and shape of the vocal folds determine the pitch and quality of the voice.
The glottis is also essential for breathing. During respiration, the vocal folds are in an open, V-shaped position, allowing air to flow into and out of the lungs. This open state ensures an unobstructed pathway for oxygen to enter the body and carbon dioxide to be expelled. The glottis opens wide during inhalation and remains open during exhalation to facilitate this air exchange.
Another function is airway protection, especially during swallowing. When food or liquid is ingested, the glottis closes tightly to prevent substances from entering the trachea (windpipe) and lungs. A flap of cartilage called the epiglottis, located above the glottis, also seals off the entrance to the larynx, providing an additional layer of defense. This dual mechanism ensures that food travels down the esophagus, preventing choking or aspiration.
Common Conditions Affecting the Glottis
Various conditions can affect the glottis and its functions, often leading to changes in voice or breathing. Laryngitis is a common condition characterized by inflammation of the vocal cords, which can result in a raspy or hoarse voice. This inflammation often arises from infections, vocal overuse, or irritation from substances like smoke.
Vocal cord nodules and polyps are noncancerous growths that can form on the vocal folds. Nodules appear as calluses, often in pairs, due to chronic vocal abuse or misuse, such as excessive singing or shouting. Polyps are softer, blister-like growths that can also impair vocal fold vibration, leading to hoarseness, a lower voice, or breathiness.
Vocal cord paralysis occurs when one or both vocal cords do not open or close properly. This condition can weaken the voice and, in some cases, make swallowing difficult, as food or liquids might enter the airway. Paralysis can stem from nerve injury due to trauma, surgery, certain medical conditions, or tumors.