Procedures
Laryngoplasty
Definition
Laryngoplasty is reparative or plastic surgery to the larynx.
Laryngeal function
The larynx or voice box is an organ in the neck involved in breathing, voice, coughing and swallowing.
The vocal cords are structures that open and close the laryngeal opening. When the vocal cords are open, breathing takes place. During swallowing the cords close the airway, to prevent food or fluid to enter the airways (aspiration). When you need to cough to expel mucus from your lungs, the cords close momentarily to build up pressure below the cords. They then open to expel the mucus from the lower airways. During speech the cords manipulate pitch and volume, which is essential for phonation. As air rushes from the lungs out through the larynx, the vocal cords vibrate, producing sound. The upper portion of the throat and mouth then modifies this sound to produce voice.
The laryngeal inlet (glottis) is V shaped. The vocal cords are joined in the front and joints at the back are moved by muscles, between an open and closed position.
Vocal Cord Palsy
Most commonly due to nerve damage (thyroid surgery, tumors etc.). May also be caused by a brain injury. Usually only one vocal cord. The paralyzed cord does not lie in the middle, but of center (paramedian). Thus, the normal cord cannot close the glottis completely. Symptoms are loss of voice, weak cough reflex and occasional aspiration. Treatment when recovery is not expected, is surgical medialization of the paralyzed vocal cord- Type 1 thyroplasty.
When both vocal cords are paralyzed, the airway becomes compromised. Both cords lie paramedian, with a limited airway. These patients have stridor or breathing difficulty. Temporary movement of one vocal cord to the side (lateralization) to increase the airway in cases where self-recovery is uncertain or expected. If no recovery is expected a more permanent solution is needed- Type 2 thyroplasty or nerve reinnervation surgery.
Plastic surgeries
Changing the voice frequency or pitch. The vocal pitch may be lowered or increased. The Adam’s apple or laryngeal prominence may be altered. In boys the laryngeal framework grows during puberty, creating the Adam’s apple. When the Adam’s apple is too prominent, it may be reshaped. When the pitch of the voice is too high, it may be lowered with surgery- Type 3 thyroplasty. If the voice pitch is too low, the pitch can be increased with surgery- Type 4 thyroplasty.
Surgical approaches
Some of the laryngeal procedures can be done through the mouth, by laryngoscopy. These include CO2 laser surgery and injections into vocal cords. Depending on the patient anatomy and the type of condition, an external approach may be required. This include an incision in the neck. Some of these procedures can be done under local anesthesia.