Laryngoscopy

Test Overview

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 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. 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.

Why It Is Done

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 trouble 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).

How To Prepare

Indirect laryngoscopy and direct flexible laryngoscopy

In general, there's nothing you have to do before this test, unless your doctor tells you to.

Direct rigid laryngoscopy

Rigid laryngoscopy is done with a general anesthetic. Do not eat or drink for 8 hours before the procedure.

Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.

Tell your doctor ALL the medicines, vitamins, supplements, and herbal remedies you take. Some may increase the risk of problems during your test. Your doctor will tell you if you should stop taking any of them before the test and how soon to do it.

If you take aspirin or some other blood thinner, ask your doctor if you should stop taking it before your procedure. Make sure that you understand exactly what your doctor wants you to do. These medicines increase the risk of bleeding.

How It Is Done

Indirect laryngoscopy and direct flexible laryngoscopy are generally done in a doctor's office. You may be awake for the test.

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.

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

Direct flexible laryngoscopy

The doctor will 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 topical 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 test. 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 this test, remove all your jewelry, dentures, and eyeglasses. You will empty your bladder before the test. 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.

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. When you feel ready, you can eat a normal diet.
• Do not clear your throat or cough hard for several hours after the laryngoscopy.
• If your child is having this procedure, the same is also true. If your child has a sore throat and is age 4 or older, you can give him or her throat lozenges. A child age 8 or older can gargle with warm salt water.

How long the test takes

How long a laryngoscopy takes is similar for the three types:

• An indirect test takes 5 to 10 minutes.
• A direct flexible test takes about 5 minutes.
• A direct rigid test takes 15 to 30 minutes.

How It Feels

Indirect 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 spray anesthetic is used, it will taste bitter. It can make you feel like your throat is swollen, and it may make you feel that it is hard to swallow.

Direct flexible laryngoscopy

It may feel strange to have the doctor put the scope up your nose. But it should not hurt. You will still be able to breathe. If a spray anesthetic is used, it may taste bitter. The anesthetic can also make you feel like your throat is swollen. You can swallow normally, but you may not feel it.

Direct rigid laryngoscopy

You will be asleep and feel nothing during the laryngoscopy.

Risks

All types of laryngoscopy have a small chance of causing swelling and blocking the airway. If your airway is partly blocked 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 may need to put a tube in your throat to help you breathe. Or, very rarely, your doctor may have to make a cut (incision) in your neck (a tracheotomy).

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

Results

If a biopsy was done, it may take several days for your doctor to know the results.

Laryngoscopy

Normal:	The throat (larynx) does not have swelling, an injury, narrowing (strictures), or foreign bodies. Your vocal cords do not have scar tissue, growths (tumors), or signs of not moving correctly (paralysis).
Abnormal:	Your larynx has inflammation, injury, strictures, tumors, or foreign bodies. Your vocal cords have scar tissue or signs of paralysis.