Figure 9a. Normal larynx. (a) Axial CT scan shows the normal appearance of the larynx during quiet respiration. The true vocal cords are abducted. (b) Volume-rendered image shows the upper airways during quiet respiration. The true and false vocal cords are poorly seen (arrows). (c) Axial CT scan obtained during phonation shows that the true vocal cords are thin and adducted. The ventricles are properly inflated (*). (d) Volume-rendered laryngogram obtained during phonation clearly shows the true (arrows) and false (*) vocal cords. The laryngeal ventricles are well demonstrated (arrowheads). The piriform sinuses are inflated.