Table 2.
The optimization objectives of the control and test plans for patients with nasopharyngeal carcinoma patients
| Structures | Optimization objectives |
|---|---|
| PTVnx | V100 ≥ 95%, D1 ≤ 77 Gy |
| PTVnd | V100 ≥ 95% |
| PTV1 | V100 ≥ 95% |
| Brain stem | D1 < 60 Gy |
| Spinal cord | D1 < 45 Gy |
| Optic nerve | D1 < 50 Gy |
| Optic chiasm | Dmax < 54 Gy |
| Lens | D1 < 10 Gy |
| Pituitary | Dmean < 50 Gy |
| Larynx | Dmean < 40 Gy |
| TM joint | Dmean < 50 Gy |
| Oral cavity | Dmean < 40 Gy |
| Parotid gland | Dmean < 35 Gy |
| Thyroid gland | Dmean < 50 Gy |
D1, dose received by 1% volume; Dmax, maximum dose; Dmean, mean dose; PTV1, planning target volume 1; PTVnd, planning target volume of lymph nodes; PTVnx, planning target volume at nasopharynx; TM, temporomandibular; V100, percentage of the volume that received 100% of the prescribed dose.