Dermal fillers such as collagen are most often used for cosmetic purposes, but they can also be used to treat mobility and structural problems in the vocal cords. These cords are made up of muscle with a membrane coating. They are located in the throat, and the vibration of these cords is responsible for creating sound and modulating its pitch and volume during speech. The sound of normal speech occurs when the two sets of vocal cords come together and touch. When the cords cannot meet in the middle, patients may have difficulty speaking loudly or even making any sound at all. To understand what this feels like, try speaking with a normal voice and then try whispering. When you whisper, the vocal cords are basically still. When you speak out loud, they vibrate and touch each other.
What Causes Problems with the Vocal Cords?
Changes in these structures often occur with aging as the muscles atrophy. Elderly patients may report that they have poor control over the pitch, range, loudness and quality of their voice as a result. Stroke can temporarily or permanently paralyze the vocal cords on one side of the voice box, leading to asymmetrical function. Chronic, progressive diseases such as Parkinson’s and ALS can also affect the shape and strength of the vocal cords over time.
Muscle atrophy from age, nerve damage or scarring from disease or trauma can cause the cords to shrink and bow away from the center line so they no longer touch properly during speech. Patients may also experience shortness of breath or difficulty keeping water out of their windpipe as a result of abnormal vocal fold structure or movement. When non-invasive therapies do not help, patients may be candidates for injection laryngoplasty with collagen or other fillers.
How Does Collagen Help?
An injection of collagen is an easy way to add bulk to the targeted tissue. The purpose of the filler is to normalize the size or position of the affected cord and allow it to function more normally. When the cord is larger and nearer its original shape and position, the patient may have more control over the volume, quality and pitch of their voice. They may also experience some relief from related symptoms with fluid intake or breathing.
Collagen is a temporary solution since it is absorbed by the body over time. However, the treatment is often still useful:
- It can be repeated as necessary to continue giving patients relief from symptoms.
- It is not highly invasive, and the risk of complications is low.
- It does not interfere with other surgeries that may be done later.
- It offers a temporary fix that keeps the patient more comfortable while nerve damage heals.
- It is a good way to test whether a permanent implant might help the patient.
What Type of Collagen Is Used for Treating Vocal Cords?
Bovine collagen (Zyderm or Zyplast) was sometimes used in the past for this treatment. However, the usual collagen filler today is Cymetra (micronized AlloDerm) derived from human tissue. It does not carry the same risk of rare but serious allergic reaction that led to bovine fillers being pulled from the U.S. market. A patient’s own collagen can also be injected, but autologous collagen is much more expensive and requires harvesting donor tissue from elsewhere on the body.
How Is the Procedure Done?
This treatment may be performed using general anesthesia; but some plastic surgeons and ENT specialists prefer to do it using local anesthesia. This allows the patient to participate in the procedure by testing their vocal cords and ensuring that the right amount of filler is injected. The risks are lower and the treatment is less expensive when the patient is awake.
The injection can be done through the mouth or through the skin on the throat. A laryngoscope (a flexible tube equipped with a camera) is passed down into the throat through the nose to visualize the cords and ensure the injections are accurate. The nasal passageways and voice box are numbed with a sprayed anesthetic to reduce gagging and discomfort. Patients who are nervous about the procedure may be offered medication to help them relax.
The injections cause some feelings of pressure that some patients find uncomfortable but manageable. The discomfort typically subsides to a low level after the injections are complete. Individuals who have paralysis in their vocal cords may experience no sensation. Patients may feel that their vocal cords are swollen and their voice is hoarse for a few days or even a couple of weeks after treatment. However, improvement in speech is usually noticeable after the first day. Results may last for three to six months before maintenance injections are needed.