 |
 |
Joan, this is from memory, I am not an expert on the collagen treatment!: The vocal cords are two flaps of tissue that almost touch, like curtains, when they are affected by Parkinson's they shrink, allowing air to pass through almost unimpeded, giving the effect of a soft voice. The collagen causes the folds to be fattened and therefor the space is almost closed between them, and the air passing through can vibrate them to produce a stronger voice. [log in to unmask]