Table 2.
Dosimetric parameters are given as mean ± standard deviation and range in parentheses
| Group A | Group B | Group C | Group D | p-value | |
|---|---|---|---|---|---|
| CTDIvol (mGy) | 11.3 ± 0.8 | 10.0 ± 1.1 | 7.8 ± 1.4 | 6.9 ± 1.3 | Groups A vs B p = 0.45; C vs D p = 0.15; |
| (10.0–12.8) | (8.1–12.7) | (5.8–13.3) | (5.0–12.1) | All other p < 0.01 | |
| DLP (mGy × cm) | 308.5 ± 43.0 | 273.7 ± 48.1 | 209.5 ± 38.4 | 188.5 ± 43.3 | Groups A vs B p = 0.41; C vs D p > 0.07, B vs C p < 0.04; |
| (186.0–376.2) | (203.3–411.1) | (155.8–359.9) | (136.1–326.7) | All other p ≤ 0.001 | |
| Effective dose (mSv) | 1.8 ± 0.2 | 1.6 ± 0.3 | 1.1 ± 0.1 | 1.0 ± 0.2 | Groups A vs B p = 0.08; C vs D p = 0.11, |
| (1.2–2.3) | (1.1–2.2) | (0.9–2.1) | (0.8–1.8) | All other p < 0.002 | |
| Mean acquisition length (cm) | 27.2 ± 3.5 | 27.4 ± 4.1 | 27.1 ± 3.4 | 27.2 ± 4.2 | All p > 0.78 |
| (18.0–33.6) | (21.0–35.0) | (17.7–34.9) | (15.8–39.3) | ||
| DLP 27 cm (mGy × cm) | 306.2 ± 22.6 | 270.2 ± 30.8 | 206.9 ± 23.1 | 185.5 ± 49.5 | Groups A vs B p = 0.23; C vs D p = 0.14; |
| (270.5–345.9) | (218.2–341.8) | (169.9–271.6) | (116.9–329.0) | All other p ≤ 0.001 | |
| Effective dose 27 cm (mSv) | 1.8 ± 0.1 | 1.6 ± 0.2 | 1.1 ± 0.2 | 1.0 ± 0.3 | Groups A vs B and C vs D p = 0.10; |
| (1.6–2.0) | (1.3–1.9) | (1.0–1.9) | (0.7–1.5) | All other p < 0.01 |
CTDIvol, CT volume dose index; DLP, Dose-length product.