Table 2.
Treatment characteristics and dose volume analyses of 100 patients
| Characteristic | |
|---|---|
| Marginal dose D95 (Gy) | 21.0 (17.0–25.0) |
| Fraction number 3/5 | 83/17 |
| Prescribed isodose (%) | 81.6 (61.0–91.4) |
| Conformity indexa | 1.4 (1.1–2.1) |
| Homogeneity indexa | 1.2 (1.1–1.6) |
| Optic nerve maximum dose (Gy) | 19.9 (1.4–25.0) |
| Optic chiasm maximum dose (Gy) | 20.3 (2.6–25.0) |
| Pituitary stalk maximum dose (Gy) | 12.5 (2.5–25.0) |
| Brain stem maximum dose (Gy) | 14.0 (3.0–25.0) |
| Collimator (mm) | |
| 7.5/10.0/12.5/15.0/20.0/25.0 | 3/13/18/17/15/4 |
Abbreviation: D95, dose delivered to 95% of the planning target volume.
*Data are presented as absolute numbers or the median (range).
aConformity index, prescribed isodose volume/target volume; Homogeneity index, maximum dose within the target volume/prescribed dose, according to the Radiation Therapy Oncology Group.23 Radiation doses were prescribed at the margin (95% volume border of the planning target volume).