Laryngoscopy

Laryngoscopy is an examination that lets your doctor look at the back of your throat, your voice box (larynx), and vocal cords with a scope (laryngoscope). There are two types of laryngoscopy, and each uses different equipment.

Indirect laryngoscopy

Indirect laryngoscopy is done in a doctor's office using a small hand mirror held at the back of the throat. Your doctor shines a light in your mouth and wears a mirror on his or her head to reflect light to the back of your throat. Some doctors now use headgear with a bright light.

Indirect laryngoscopy is not done as much now because new flexible laryngoscopes let your doctor see better and are more comfortable for you.

Direct fiber-optic (flexible or rigid) laryngoscopy

Direct laryngoscopy lets your doctor see deeper into your throat with a fiber-optic scope. The scope is either flexible or rigid. Flexible scopes show the throat better and are more comfortable for you. Rigid scopes are often used in surgery.

An indirect or direct laryngoscopy helps a doctor:

• Find the cause of voice problems, such as a breathy voice, hoarse voice, weak voice, or no voice.
• Find the cause of throat and ear pain.
• Find the cause for difficulty in swallowing, a feeling of a lump in the throat, or mucus with blood in it.
• Check injuries to the throat, narrowing of the throat (strictures), or blockages in the airway.

Direct rigid laryngoscopy may be used as a surgical procedure to remove foreign objects in the throat, collect tissue samples (biopsy), remove polyps from the vocal cords, or perform laser treatment. Direct rigid laryngoscopy may also be used to help find cancer of the voice box (larynx).

Indirect and direct flexible laryngoscopy

Your doctor will give you instructions about not eating or drinking before the examination to prevent vomiting. If you wear dentures, you will remove them just before the examination.

Direct rigid laryngoscopy

Before a rigid laryngoscopy, tell your doctor if you:

• Are allergic to any medicines, including anesthetics.
• Are taking any medicines.
• Have bleeding problems or take blood-thinning medicine, such as warfarin (Coumadin).
• Have heart problems.
• Are or might be pregnant.
• Have had surgery or radiation treatments to your mouth or throat.

Rigid laryngoscopy is done with a general anesthetic. Do not eat or drink for 8 hours before the procedure. If you have this test in your doctor's office or at a surgery center, arrange to have someone drive you home after the procedure.

You will also be asked to sign a consent form. Talk to your health professional about any concerns you have regarding the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test, fill out the medical test information form(What is a PDF document?).

Flexible laryngoscopy examinations are generally done in a doctor's office. Most fiber-optic laryngoscopies are done by an ear, nose, and throat specialist (ENT). Some other doctors may also do this examination, such as family medicine doctors, internists, emergency medicine doctors, critical care medicine specialists, allergy specialists, and pulmonologists. You may be awake for the examination.

Indirect laryngoscopy

You will sit straight up in a chair and stick out your tongue as far as you can. The doctor will hold your tongue down with some gauze. This lets the doctor see your throat more clearly. If you gag easily, the doctor may spray a numbing medicine (local anesthetic) into your throat to help with the gaggy feeling.

The doctor will hold a small mirror at the back of your throat and shine a light into your mouth. He or she will wear a head mirror to reflect the light to the back of your throat. Or your doctor may wear headgear with a bright light hooked to it. He or she may ask you to make a high-pitched "e-e-e-e" sound or a low-pitched "a-a-a-a" sound. Making these noises helps the doctor see your vocal cords.

The examination takes 5 to 10 minutes.

If a local (topical) anesthetic is used during the examination, it will last about 30 minutes. You can eat or drink when your throat is no longer numb.

Direct flexible laryngoscopy

The doctor may also use a thin, flexible scope to look at your throat. You may get a medicine to dry up the secretions in your nose and throat. This lets your doctor see more clearly. A local anesthetic may be sprayed on your throat to numb it.

The scope is put in your nose and then gently moved down into your throat. As the scope is passed down your throat, your doctor may spray more medicine to keep your throat numb during the examination. The doctor may also swab or spray a medicine inside your nose that opens your nasal passages to give a better view of your airway.

Direct rigid laryngoscopy

Before you have a rigid laryngoscopy, remove all your jewelry, dentures, and eyeglasses. You will empty your bladder before the examination. You will be given a cloth or paper gown to wear.

Direct rigid laryngoscopy is done in a surgery room. You will go to sleep (general anesthetic) and not feel the scope in your throat.

You will lie on your back during this procedure. After you are asleep, the rigid laryngoscope is put in your mouth and down your throat. Your doctor will be able to see your voice box (larynx) and vocal cords.

The rigid laryngoscope may also be used to remove foreign objects in the throat, collect tissue samples (biopsy), remove polyps from the vocal cords, or perform laser treatment.

The examination takes 15 to 30 minutes. You may get an ice pack to use on your throat to prevent swelling. After the procedure, you will be watched by a nurse for a few hours until you are fully awake and able to swallow.

• Do not eat or drink anything for about 2 hours after a laryngoscopy or until you are able to swallow without choking. You can then start with sips of water and eat a normal diet.
• Do not clear your throat or cough hard for several hours after the laryngoscopy.
• If your vocal cords were affected during the laryngoscopy, rest your voice completely for 3 days.
• If you speak, do so in your normal tone of voice and do not talk for very long. Whispering or shouting can strain your vocal cords as they are trying to heal.
• You may sound hoarse for about 3 weeks after the laryngoscopy if tissue was removed.

Indirect and direct flexible laryngoscopy

You may feel like gagging when the mirror is placed in your throat. It may be uncomfortable when the doctor pulls on your tongue. If this becomes painful, signal your doctor by pointing to your tongue, since you will not be able to speak. If a local anesthetic is used, it tastes bitter, it can make you feel like your throat is swollen, and it may make you feel that it is hard to swallow.

Direct rigid laryngoscopy

You will be asleep and feel nothing during the laryngoscopy. After the procedure, you may have some nausea, general muscle aches, and may feel tired for 1 to 2 days. You also may have a sore throat and sound hoarse. Suck on throat lozenges or gargle with warm salt water to help your sore throat.

If a biopsy was taken, it is normal to spit up a small amount of blood after the laryngoscopy. Talk to your doctor about how much bleeding to expect and how long the bleeding may last. Call your doctor immediately if you:

• Have a lot of bleeding or if the bleeding lasts for 24 hours.
• Have any difficulty breathing.

All types of laryngoscopy have a small chance of causing swelling and blocking the airway. If you have a partially blocked airway because of tumors, polyps, or severe inflammation of the tissues at the back of the throat (epiglottitis), you may have a higher chance of problems.

If complete blockage of the airway occurs, which is rare, your doctor will make a cut (incision) in your neck to help you breathe (a tracheotomy).

If a biopsy was taken, there is a very small chance of bleeding, infection, or a tear in the airway.

Laryngoscopy is an examination that lets your doctor look at the back of your throat, your voice box (larynx), and vocal cords with a scope (laryngoscope). If a biopsy was done, it may take several days for your doctor to know the results.

If you gag easily, your doctor may need to do a direct rigid laryngoscopy.

• Direct rigid laryngoscopy is generally recommended for:
  • Children.
  • People who gag easily because of abnormalities in their throat structure.
  • People who may have symptoms of laryngeal or pharyngeal disease.
  • People who have not responded to treatment for laryngeal symptoms.

Other Works Consulted

• Rowe LD (2006). Larynx of otolaryngology—Head and neck surgery. In GM Doherty, ed., Current Surgical Diagnosis and Treatment, 12th ed., pp. 967. New York: McGraw-Hill.