TABLE II.
Treatment parameters
| Parameter | Mediana | Rangea |
|---|---|---|
| Planning target volume (ptv [cm3]) | 33.5 | 3.1–75 |
| Total dose (Gy) | 50.4 | 45–60 |
| Fractions (n) | 28 | 23–33 |
| Fields (n) | 5 | 4–6 |
| Prescription isodose surface (%) | 90.1 | 76.9–95.2 |
| Conformity index | 1.4 | 1.2–1.8 |
| Dose covering 99% of the ptv (%) | 98 | 94–100 |
| Maximum dose to the chiasm (Gy) | 52.9 | 44.3–55.5 |
| Mean dose to the chiasm (Gy) | 42.6 | 18.6–49 |
| Maximum dose to optic nerves (Gy) | 51.2 | 17–55.4 |
| Mean dose to the left optic nerve (Gy) | 15.3 | 5–28.5 |
a
Average calculation for all patients.