Table 2.
Median (range) CI (V95%/PTV) and dose statistics for PTVm − sc, PTVe, PRVsc, SCring and RVR are shown. Doses are in Grays and volumes are in percent
| ROI | VMAT | IMRT | |
| CI | V95%/PTV | 1.30 (1.02–1.96) | 1.54 (1.20–2.41) |
| PTVm − sc | D95% | 31.4 (31.3–32.9) | 30.7 (30.3–32.4) |
| D90% | 32.8 (32.2–33.6) | 31.9 (31.5–33.3) | |
| V95% | 87.1 (81.0–92.5) | 82.6 (77.6–90.2) | |
| PTVe | D95% | 19.8 (19.5–20.3) | 19.8 (19.4–19.9) |
| D90% | 20.4 (19.8–20.9) | 20.1 (19.8–20.6) | |
| V95% | 99.3 (98.6–99.6) | 99.6 (99.2–100.0) | |
| PRVsc | D1 cm3 | 22.5 (21.9–23.5) | 22.0 (21.9–22.2) |
| SCring | Dmin | 18.1 (15.8–19.6) | 19.2 (18.2–19.5) |
| Dmean | 23.2 (22.3–25.1) | 23.0 (22.5–24.4) | |
| RVR | V10 Gy | 11.0 (9.4–18.9) | 14.6 (9.8–36.6) |
| Dmean | 5.1 (4.4–6.1) | 4.9 (3.8–7.8) |
D, dose; CI, conformity index; IMRT, intensity modulated radiotherapy; PRVsc, planning risk volume of the spinal cord; PTV, planning target volume; PTVe, elective PTV; PTVm − sc, macroscopic PTV minus a 3-mm expansion of the spinal cord; ROI, region of interest; RVR, remaining volume at risk; SCring, ring around the spinal cord; V, volume; VMAT, volumetric modulated arc therapy.