When we speak air is pushed up from our lungs through the voice box, the larynx.  The larynx lies in the front of the throat, and contains the vocal cords.  The vocal cords are two folds of tissue that vibrate together to create the sounds that make our voice.

Sometimes a lung cancer can damage the nerve that works one or other of the vocal cords.  This leads to a paralysis of one of the cords, which causes either hoarseness, weakness or a complete loss of the voice.

To work properly the vocal cords must meet together when they vibrate.  If one of the cords is paralysed this leaves a gap between them, which leads to the loss of voice.

If the voice is severely affected it may be possible to do a small operation that might help.  The operation is designed to push the paralysed cord over towards the other vocal cord, so that the two can meet. 

There are two types of surgery that are used to do this. One is called thyroplasty, and uses a small plastic implant to push the cord across, and keep it in place.  The other uses an injection of Teflon into the paralysed cord to make it swell and close the gap between the cords. 

These are quite small operations, and can be done under either a local or a general anaesthetic. Thyroplasty is a reversible procedure, as the implant can be removed later, if necessary, but the Teflon injection permanently changes the vocal cord.

If your father’s loss of voice is troubling him then do get him to ask his doctors if one of these operations might help.