People burdened by severely damaged vocal cords have new reason to hope they could someday get their voices back. Tissue engineers have for the first time made structures that not only resemble real vocal cords but also function like them.
Impaired vocal cords make it hard or impossible for people to speak. There is currently no way to fix severe damage, which can result from surgery, traumatic injury, or diseases like cancer. So researchers at the University of Wisconsin are trying to engineer replacements.
The researchers implanted the engineered tissue into a larynx that had been taken from a dog and had one of its vocal cords removed. They demonstrated that the lab-made tissue vibrates and sounds like healthy tissue. (Click on the video below to hear the sound the tissue makes when researchers push air through the larynx.) Further tests in mice showed that the tissue elicited a minimal immune response, raising the researchers’ hopes that such implants could eventually work in people.
Vocal cords are bands of tissue stretched horizontally on either side of the larynx, or voice box, just above the trachea, or windpipe. They open during breathing and vibrate when a person is using his or her voice. Restoring the voice of someone with a badly damaged vocal cord is challenging because the tissue must thrive under unique biomechanical conditions. Its precise structure and makeup is what makes it able to withstand frequent stress, strain, and vibration.