| RV | Mean radiation dose |
---|
| r | P value | r | P value |
---|
Mid-RT |
RT2 | 0.092 | 0.525 | 0.087 | 0.530 |
RFF | 0.038 | 0.820 | 0.121 | 0.591 |
Post-RT |
RT2 | 0.313 | 0.027a | −0.106 | 0.444 |
RFF | −0.029 | 0.863 | −0.419 | 0.052 |
- Note: Pre-RT within 2 weeks before radiotherapy, mid-RT 5 weeks after the beginning of radiotherapy, post-RT 4 weeks after radiotherapy. RV, RT2 and RFF are the change rates of parotid volume, T2 value and fat fraction (FF) compared with pre-RT, respectively. a P < 0.05 with Pearson’s correlation test