Figure 6

<p>A. Measurement of depth of the remaining viable cell surface. Objective measurement of the depth (Dp) of the remaining viable cell surface layer in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes of phonation. Measurement bar represents 4 µm. B. Objective examination of depth of the remaining viable cell surface using TEM. Average depth (µm) of the remaining viable cell surface in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions for 30, 60, and 120 minutes. * Denotes a significant difference between groups (p<0.0167).</p

Figure 4

<p>A. SEM representative images for control, modal intensity, and raised intensity phonation. Representative 2×2 µm SEM images for the control, modal intensity, and raised intensity phonation conditions after 30, 60, and 120 minutes of phonation. Measurement bar represents 0.5 µm. B. Visual examination of epithelial surface microprojections. Classification of images by damage severity using routine visual examination of epithelial surface microprojections. Four categories of damage severity: extensive (black fill), moderate (dark gray fill), minimal (light gray fill), and normal (white fill) in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes of phonation. C. Objective examination of epithelial surface microprojection density using SEM. The percentage of vocal fold surface covered by microprojections in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes of phonation. * Denotes a significant difference between groups (p<0.01).</p

Figure 5

<p>A. Measurement of epithelial surface microprojection density and height. Objective measurement of the density (Dn) and height (H) of vocal fold epithelial surface microprojections in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes of phonation. Measurement bar represents 1 µm. B. Objective examination of epithelial surface microprojection density using TEM. The number of microprojections per 10 µm field in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes. * Denotes a significant difference between groups (p<0.0167). C. Objective examination of epithelial surface microprojection height using TEM. Average height (µm) of microprojections in the control (C), modal intensity phonation (M), and raised intensity phonation (R) conditions after 30, 60, and 120 minutes. * Denotes a significant difference between groups (p<0.0167).</p

SEM image of a rabbit vocal fold.

<p>Scanning electron microscopy image of a rabbit vocal fold. Large box represents the central portion of the middle one-third region of the vocal fold. Small box represents a 2×2 µm image used for SEM analysis.</p

Damage severity descriptions used for visual evaluation of microprojections.

<p>All images were categorized into four groups according to the degree of surface damage. (1) extensive – the cell surface was destroyed and cytoskeleton was exposed; (2) moderate – all microprojections were damaged and appeared flat or normal; (3) minimal – microprojections were slightly damaged; and (4) normal – microprojections showed no damage.</p