Measurement of stapedius contraction during vocalization effort in patients after laryngectomy or tracheostomy

The contraction of the stapedius muscle during the effort of vocalization w as examined by measurement of acoustic compliance in subjects who had under gone laryngectomy or tracheostomy. No significant level of persistent compl iance change was recorded in any of the subjects, indicating the absence of effective contraction of the stapedius during the vocalization effort. In two subjects who use an electrolarynx, although no significant compliance c hange resulted from the simple vocalization effort without the electrolaryn x (no actual vocalized sound), a remarkable level of persistent compliance change was observed during the vocalization using the electrolarynx. These results seem to indicate that a simple vocalization effort without actual v oice cannot elicit effective contraction of the middle ear muscles, and tha t sound generation during vocalization is essential for effective contracti on of the middle ear muscles during vocalization, at least in some human su bjects. (C) 2000 Elsevier Science B.V. All rights reserved.