Laryngoscopy is a visual examination below the back of the throat, where the voice box (larynx) containing the vocal cords is located.The procedure is done by using mirrors and a light source at the back of the throat, or by inserting a thin instrument (a laryngoscope) through the nose or mouth into the throat. This scope lights and magnifies images within the throat.
Laryngoscopy is an effective procedure for discovering the causes of voice and breathing problems, pain in the throat or ear, difficulty in swallowing, narrowing of the throat (strictures or stenosis), and blockages in the airway. The procedure can also help diagnose problems in the vocal cords.The procedure is relatively painless, but the idea of having a scope inserted into the throat can be a little scary, so it helps to understand how a laryngoscopy is done. The following basics will help you understand what is happening and help put your child at ease.
The larynx, or voice box, is the organ that produces voice. Found inside the neck, right at the top of the windpipe, or trachea, it contains two bands of tissue called vocal cords, or vocal folds. When we breathe, the vocal cords spread apart so that air can pass into and out of the lungs. But when we speak the cords come together, causing the air from the lungs to pass through a smaller space. This causes the vocal cords to vibrate. The sound from these vibrations goes up the throat and comes out of the mouth as sound. The larynx also plays an important role in protecting lungs by preventing foreign matter from entering the lower airway.
The three kinds of laryngoscopy are:
- indirect laryngoscopy
- fiber-optic (flexible) laryngoscopy
- direct laryngoscopy
The indirect procedure can be performed in a doctor’s office using a small hand mirror, which is held at the back of the throat. The doctor will aim a light at the back of the throat, usually by wearing headgear that has a bright light attached. This technique will help the doctor examine the larynx, vocal cords, and hypopharynx, which is a part of the passageway to the lungs and stomach. Indirect laryngoscopy is not typically used with children, as it tends to cause gagging and can be hard for kids to tolerate.
Fiber-optic (flexible) laryngoscopy / Direct laryngoscopy
Fiber-optic or direct laryngoscopy examinations are usually done by an ear, nose, and throat specialist (ENT). The examination allows the doctor to see deeper into the throat by using either a flexible or rigid telescope.
Rigid telescopes are more often used as part of a surgical procedure in evaluating children with stridor (a noisy, harsh breathing) and removing foreign objects in the throat and lower airway. They are also used in collecting tissue samples (a biopsy), laser treatments, and in locating cancer of the larynx.
Why Is Laryngoscopy Performed?
- Laryngoscopy is performed to:
- diagnose a persistent cough, throat pain, bleeding, hoarseness, or bad breath
- check for inflammation
- discover a possible narrowing or blockage of the throat
- visualize a mass or tumor in the throat or on the vocal cords
- diagnose difficulty swallowing
- diagnose suspected cancer
- evaluate causes of persistent earache
- diagnose voice problems, such as weak voice, hoarse voice, breathy voice, or no voice
- Laryngoscopy is also performed to remove foreign objects stuck in the throat or to biopsy a growth in the throat or on the vocal cords.
Preparing for the Procedure
Talk to your doctor about the kind of test being performed, how it will be done, the risks, and the results. Having your questions answered beforehand will help reduce your concerns and give you and your child a better understanding of how the procedure will go.
In many cases, the doctor will have the child undergo a physical exam, chest X-ray, or CT scan (a type of X-ray that uses a computer to take pictures of the inside of the body). Your child may also be asked to swallow a liquid called barium while a series of X-rays of the larynx and esophagus are taken. Barium liquid is harmless and will pass through the body within a day or two. These measures will help your doctor further understand the physical symptoms your child may be having. If general anesthesia will be used, your doctor will give you instructions about your child not eating or drinking before the exam (this is to prevent vomiting). For an office laryngoscopy in which local anesthesia is used, your child will not need to avoid eating or drinking beforehand.
Your doctor may decide to do a direct laryngoscopy if, among other possible reasons, your child gags easily or the airway below the vocal folds needs to be examined. This is done using general anesthetic, so it is important for your child to avoid eating or drinking 8 hours before the procedure.
Also before a direct laryngoscopy, tell the doctor if your child:
- has heart problems
- is taking any medications
- has allergies to any medications, including anesthetics
- has bleeding problems or is taking blood-thinning medicine
- has had recent surgery or radiation treatments to the mouth or throat
During the Procedure
Indirect laryngoscopy and fiber-optic laryngoscopies often are performed in the doctor’s office, sometimes using local anesthetic. These procedures usually take only 5 to 10 minutes.
Your child will be asked to sit up straight in a high-backed chair with a headrest. The chair will allow your child’s head and jaw to move forward. Your child will open his or her mouth wide, and the doctor will spray the throat with an anesthetic or numbing medication. Your child will gargle and then spit out. The doctor will then cover the tongue with gauze and hold it down. The doctor will hold up a warm mirror to the back of the throat. With a light that is usually attached to headgear the doctor is wearing, the doctor will tilt the mirror to view various areas of the throat. Your child may be asked to make high-pitched or low-pitched sounds so that the doctor can view the larynx and see the vocal cords move.
In a fiber-optic laryngoscopy the doctor will use a fiber-optic laryngoscope, which is a thin, flexible instrument that lights and magnifies images, providing a better view of the larynx and vocal cords. The doctor will determine if this procedure is to be done in the operating room under general anesthesia or in the office. The procedure typically does not require a hospital stay. Sometimes numbing medication is sprayed or swabbed in the nose or throat before the procedure. The flexible scope will be inserted through the nostril or the mouth. The doctor will examine the throat area through the scope’s eyepiece. Sometimes the images are displayed on a monitor so that family members can see what the doctor is seeing.
Direct laryngoscopy is done in an operating room and your child will be put under general anesthesia and not feel the scope in his or her throat. Before the direct laryngoscopy procedure, have your child remove all jewelry and eyeglasses. Your child will be asked to empty his or her bladder and then to change into a cloth or paper gown, which will be provided. Inside the operating room, your child will lie on his or her back and the laryngoscope will be placed through the mouth, into the throat. IV fluids and medications, such as antibiotics or steroids, may be administered. If needed, the doctor will remove foreign objects in the throat, collect tissue samples, perform laser treatment, or remove growths from the vocal cords. The examination can take as little as 15 to 30 minutes, but may take much longer if specific treatments are required.
How It Feels
Indirect and fiber-optic laryngoscopy
When the doctor places the mirror at the back of the throat, it may cause gagging. Similarly, your child may become uncomfortable when the doctor pulls on the tongue. If it becomes too painful, your child can signal to the doctor, since speaking will be difficult. If a local anesthetic is used, it may taste bitter and make your child feel like his or her throat is swollen. Ask your child to try to breathe normally and remind him or her that the exam will be over within a few minutes.
For a direct laryngoscopy procedure, your child will be asleep under anesthesia and will not feel anything.
After the Procedure
If a local anesthetic or topical numbing spray was used during the examination, it will wear off in about 30 minutes. Your child should not eat or drink anything for about 2 hours, until the spray has worn off and the throat is no longer numb.
After a direct laryngoscopy, your child will be watched by a nurse until fully awake and able to swallow. This usually takes about 2 hours. In some cases, an overnight hospital stay may be required. Your child may have some nausea, general muscle aches, and feel tired for a day or two. Gargling and sucking on throat lozenges will help with the soreness, and pain medication will be given, if needed. Your child may sound hoarse or have noisy breathing for a few days after the procedure. This is normal. If the hoarseness persists, or your child is having difficulty breathing, check with your doctor.
The doctor will explain the findings after the procedure. If a biopsy was obtained, a laboratory will examine the removed tissue biopsies and provide a written report to your doctor, who will discuss the results and treatment options with you. Usually, biopsy results take about 3 to 5 days. Depending on the outcome of the exam, an office visit or a follow-up procedure may be scheduled with your doctor for 4 to 6 weeks after the initial procedure. Your doctor will discuss this with you.
Having your child undergo laryngoscopy is one of the best ways to find and treat the causes of voice problems, difficulty swallowing, persistent sore throats or hoarseness, or trouble with vocal cords. Laryngoscopy is also an excellent way to retrieve foreign objects from the throat, windpipe, or lungs, or clear blockages in the airway.
Risks and Complications
Laryngoscopy is considered an extremely effective medical exam. However, as with most procedures, there are some risks, including:
In some cases, anesthesia medications can cause complications in children (such as irregular heart rhythms, breathing problems, and, in very rare cases, death). These complications are not common. Allergic reactions also are not common. If they do occur, they typically develop within a few minutes after the anesthesia is given. The doctors can provide immediate medical attention if that happens.
Inserting a laryngoscope down the throat has the potential to cause swelling of the airways and breathing difficulties. Sometimes the airway is already blocked by the foreign body or condition that caused the problem in the first place. In very rare cases, doctors may need to perform a tracheotomy (a small incision made in the neck and windpipe, or trachea) to allow air into the lungs.
Bleeding or infection
If a biopsy was taken, there’s the rare possibility of bleeding or infection at the site. When your child is having any kind of procedure, it’s understandable to be a little uneasy. But it helps to know that in most cases, laryngoscopies are routine procedures and complications are rare. If you have any questions about laryngoscopies, speak with your doctor.
Dr. Heba Abdel Mawgoud Mohamed
MBBCh, MSc (Otorhinolaryngology)
GMC Hospital & Research Centre, Fujairah