At age 72 he fell and hit his head with a brain hemorrhage which was drained. His voice became very soft after the surgery. Over 4 months he gradually recovered about 70% of his volume but he runs out of breath quickly. His voice cracks frequently and fades out with use. He is naturally a quiet person, rating his talkativeness as a 3/7.
In this case, vocal capabilities pattern matching yields the following. His voice is soft and airy during reading. As he goes down in pitch, his voice is gravelly or rough. On maximum phonation time testing the duration is 21 seconds with a lot of breathiness. His highest pitch is about an octave above his speaking pitch and he leaks air. He does have normal vocal entrainment with yelling, suprising his wife how normal his voice sounds.
Vocal capabilities pattern matching directs our endoscopic exam to take place at both low and high volume, so that we can compare his abnormal vibrations at low volume with his normal vibrations at high volume. The pathology causing the problem should be most visible at low pitch with low volume.
With vocal cord bowing, air leak is greater at low pitch when the concave vocal cords allow the most air to escape. Since the thyroarytenoid muscles are still functioning, with the increased subglottic pressure during a yell, they can maintain tension and vibrate normally.