Glottis

What is the glottis?

Your glottis is the middle region inside your larynx (voice box) that’s made up of your vocal folds (vocal cords), the space between them and the cartilages that move them.

Most people think of the larynx primarily as the box that houses the two muscular bands of tissue responsible for your voice — your vocal folds. But of all the parts that make up the larynx, only the glottis contains your vocal cords. It’s thanks in part to your glottis (and the vocal cords within) that you’re able to speak and communicate in sounds others recognize as you.

What is the function of the glottis?

Your glottis is an important part of your airway that houses your vocal cords. Your voice can’t make sounds unless your vocal cords come together and are blown into vibration by airflow. These elements come together within your glottis.

Your glottis:

• Allows you to breathe: Your vocal cords usually rest in an open position like a “V” in your glottis. When you inhale, air from your nose and/or mouth passes between your open vocal cords on the way to your windpipe and then your lungs. Your vocal cords are also open as you breathe out.
• Prevents you from getting food or liquid in your lungs: When you swallow, a flap called the epiglottis (located above your glottis) seals off the entrance to your larynx. That way, food goes down your esophagus (food tube) instead of your windpipe. At the same time, your vocal cords close within your glottis. This is another layer of protection to keep food/liquid from entering your airway.
• Helps you make sound: When you start to talk or sing, your vocal cords meet in a closed position. Exhaled air traveling from your lungs reaches the space right below your vocal cords and, when that airflow is powerful enough, blows the vocal folds into vibration. This vibration within your glottis creates sound waves that allow you to speak and make sound in general.

Glottal stop

Attempting a glottal stop can help you experience how your glottis helps you speak. Most sounds start in your glottis and develop more unique qualities as they pass through the space above your glottis and into sinuses and your mouth. But with a glottal stop, the sound starts and stops in your glottis.

To do a glottal stop, you break up the airflow in your glottis while you’re making a vowel sound. Imagine saying “uh-oh” or pronouncing the word “city” without pronouncing the “t.” When you do this, your vocal cords vibrate when you start the word and shut quickly in the middle (after the “uh” in uh-oh or the “ci” in city when you don’t pronounce the “t”). You stop the sound in your glottis. Now, say “city,” but pronounce the “t,” so you’re avoiding a glottal stop.

Note the difference between how the words feel and sound when they stop in your glottis versus how you experience them without the glottal stop.

Where is the glottis located?

Your glottis is behind your Adam’s apple (the notch of the thyroid cartilage). It’s in between the top region of your larynx (the supraglottis) and the bottom region (the subglottis).

• The supraglottis extends from the top of your hyoid bone (the crescent-shaped bone at the front of your neck) down to your glottis. It contains your epiglottis and folds of mucous membrane called ventricular folds. The ventricular folds are sometimes called “false vocal cords.”
• The glottis extends from the bottom of the supraglottis to the top of the subglottis.
• The subglottis extends from the bottom of your glottis to the bottom of the cricoid cartilage (a ring of cartilage around your windpipe).

What are the parts of the glottis?

The glottis includes two primary structures: your vocal cords and the opening between them, the rima glottidis.

• Your vocal cords are two muscular bands of tissue that control your voice pitch (how high or low your voice sounds). Vocal cords that are bigger and thicker produce lower pitches than vocal cords that are smaller and thinner.
• Your rima glottidis is the opening between your vocal cords. An opened rima glottidis allows air to flow in and out between your vocal cords. When you speak, the rima glottidis is in a closed position. Airflow blows the vocal folds into motion. Their vibration against each other in this closed position creates sound.

Your glottis also contains cartilage, ligaments and muscles that support your vocal cords and allow you to move them. Although the size and weight of your vocal cords are primarily responsible for your pitch, how you position them plays a role, too. These muscles can become more tense or relaxed for different styles of speaking and singing (for example, mimicking a breathy voice or belting out a tune).

What does the glottis look like?

If you were to look directly down on your glottis, it may remind you of a cat’s eye. Imagine the rima glottidis as the spindle-like pupil (black opening of your eye) and the vocal cords as the symmetrical left and right sides of the pupil.

Your glottis looks different depending on whether your rima glottidis is opened or closed. When it’s closed, your vocal cords come together to form a slit. When the rima glottidis is opened, you’ll see a V-shape, with your vocal cords making up the left and right sides of the “V.”

What conditions and disorders affect the glottis?

Conditions and disorders that may affect your glottis include:

• Glottic stenosis: A form of laryngeal stenosis, glottic stenosis happens when your glottis is too narrow. You may be born with glottic stenosis. Or you may develop it when scar tissue forms after an injury or infection.
• Glottic insufficiency: With this condition, your vocal cords don’t close as they should when you speak. This can increase your risk of aspiration (food or liquids going down your windpipe) and can cause symptoms like hoarseness and trouble swallowing.
• Glottic cancer: A type of laryngeal cancer, glottic cancer starts in your vocal cords or the surrounding supportive tissue in your glottis.

Conditions that affect your vocal cords also affect your glottis. These include:

• Laryngitis (most common).
• Laryngospasm.
• Muscle tension dysphonia.
• Reinke’s edema.
• Spasmodic dysphonia.
• Inducible laryngeal obstruction (previously called vocal cord dysfunction).
• Vocal cord nodules, polyps and cysts.
• Vocal cord paralysis or paresis.

Common signs or symptoms of an issue with the glottis

Signs and symptoms of a condition affecting your glottis include:

• Hoarseness (dysphonia).
• Pain or discomfort with swallowing or talking.
• Sore throat or cough.
• Trouble swallowing (dysphagia).
• Trouble breathing (dyspnea).

Common tests to check the health of the glottis

Depending on your symptoms, you may need to see a specialist to diagnose disorders affecting your glottis. Providers include laryngologists (specialized ENTs who treat conditions affecting your voice box) and specialized speech-language pathologists (SLPs).

Tests you may need include:

• Tests that use a special camera to look at your glottis up close, including laryngoscopy and videostroboscopy.
• Imaging tests to check for structural abnormalities, such as a CT scan (computed tomography scan) or MRI (magnetic resonance imaging).
• Lab tests to check for infections, including blood tests and a throat culture.
• Tests that examine tissue samples for signs of cancer, like a biopsy.

What are common treatments for conditions affecting the glottis?

Common treatments include:

• Medications to treat infections and inflammation or relieve pain.
• Voice therapy.
• Vocal rest (not speaking or singing).
• Surgery.

How do I take care of my glottis?

Taking care of your glottis mostly involves taking steps to protect your vocal cords. You should:

• Avoid using tobacco and limit your alcohol intake: Using tobacco products and consuming too much alcohol increases your risk of glottic cancer. Smoking and drinking alcohol can also dry out your vocal cords. This makes them more susceptible to injury.
• Stay hydrated: Adequate hydration means that your vocal cords don’t have to work as hard to vibrate. This makes voice use feel easier and reduces your chances of injury. Hydration also thins out and loosens secretions that can pool in your glottis and make you have to cough or clear your throat constantly. Constant coughing isn’t good for your vocal cords.
• Prevent respiratory infections: Take steps to avoid getting sick, like washing your hands frequently and steering clear of people with colds until they’re well.
• Limit contact with irritants: Avoid environments with lots of dust or chemicals that can irritate your throat.
• Avoid straining your voice: If you’re hoarse or your voice is feeling weak, try to avoid speaking for a while. Use a microphone if you have to speak but need to rest your voice. 

A note from Cleveland Clinic

The idea of a “voice box” may sound simple, but your larynx is actually a complex structure with several parts, including the glottis. Knowing about your glottis can help you understand more about how your vocal cords work. It can help you care for them. Your glottis may only make up a tiny portion of your throat, but it plays a major role in helping you breathe, speak and sound like you.