Volume-of-Interest Values for Various Lesions in Trachea and Larynx
| Angle | Volume of interest | Volume (mm3) | Mean (a.u.) | SD (a.u) | Distance L–A (cm) | A/L (%) | Ac/Lc (%) |
| 20° | Trachea | 464.8 | 2.36 × 10−2 | 2.56 × 10−3 | — | — | — |
| Upper artifact | 500.0 | 4.90 × 10−3 | 2.56 × 10−3 | 2.0 | 20.8 | 19.3 | |
| Lower artifact | 388.7 | 4.95 × 10−3 | 3.21 × 10−3 | 2.0 | 21.0 | 25.1 | |
| Epiglottis | 849.6 | 8.83 × 10−3 | 2.01 × 10−2 | — | — | — | |
| Artifact tubercle | 714.8 | 3.43 × 10−3 | 3.52 × 10−3 | 3.0 | 38.9 | 46.2 | |
| 35° | Trachea | 527.3 | 1.49 × 10−2 | 1.91 × 10−2 | — | — | — |
| Upper artifact | 414.1 | 4.29 × 10−3 | 4.13 × 10−3 | 1.5 | 28.8 | 36.7 | |
| Lower artifact | 304.7 | 4.54 × 10−3 | 2.88 × 10−3 | 1.5 | 30.4 | 52.7 | |
| Epiglottis | 541.0 | 1.01 × 10−2 | 1.97 × 10−2 | — | — | — | |
| Artifact tubercle | 369.1 | 4.62 × 10−3 | 4.38 × 10−3 | 2.5 | 46.6 | 67.0 |
a.u. = arbitrary units; L = lesion volume of interest; A = artifact volume of interest; A/L = ratio between activities within artifact volume of interest and lesion volume of interest; Ac/Lc = ratio between activity concentrations within artifact volume of interest and lesion volume of interest.