Table 1.
Spatial variables for neutral, comfortable chin-down, and chin-tuck postures
| Neutral | Comfortable chin-down | Strict chin-tuck | |
|---|---|---|---|
| Distance at rest (mm) | |||
| Epiglottic base-posterior wall* | 19.70 (3.28)e | 19.38 (4.25)f | 17.89 (3.26)e,f |
| Epiglottic base-arytenoid* | 16.36 (5.00)e | 15.72 (4.90) | 14.03 (4.27)e |
| Hyoid bone-vocal cord* | 36.92 (6.19)d,e | 34.14 (6.73)d,f | 30.78 (7.22)e,f |
| Chin-posterior wall* | 80.66 (7.00)e | 80.19 (8.13)f | 74.67 (8.22)e,f |
| Hyoid bone, maximal excursion (mm) | |||
| Vertical | 11.43 (4.80) | 10.63 (5.21) | 12.02 (4.89) |
| Horizontal* | 12.55 (2.59)e | 12.14 (2.99)f | 9.64 (3.03)e,f |
| 2D | 14.59 (3.43) | 14.29 (3.89) | 13.93 (3.92) |
| Epiglottic base, maximal excursion (mm) | |||
| Vertical* | 13.33 (4.48)e | 13.43 (4.68)f | 15.79 (4.67)e,f |
| Horizontal* | 10.73 (3.97)d | 12.66 (4.52)d | 11.61 (3.72) |
| 2D (Posterior-upward)* | 13.26 (4.71)e | 14.16 (4.91)f | 16.25 (4.38)e,f |
| Epiglottic flip angle, degrees (°) | 111.37 (21.65) | 118.55 (22.32) | 119.68 (31.31) |
| Vocal cords, maximal excursion (mm) | |||
| Vertical* | 21.13 (5.56)a | 18.86 (5.82)a | 19.01 (6.18) |
| Horizontal* | 6.64 (2.13)b,d | 4.69 (1.55)d | 5.32 (2.61)b |
| 2D | 21.84 (6.28)a,b | 19.50 (5.65)a | 19.24 (6.83)b |
2D two-dimensional
* p < 0.01 using a repeated-measure ANOVA
a,b,cSignificantly different at p < 0.05 by Bonferroni-corrected pairwise comparisons
d,e,fSignificantly different at p < 0.01 by Bonferroni-corrected pairwise comparisons