Table 1.

Dynamic changes of parotid MR parameters during radiotherapy

	pre-RT	mid-RT	post-RT
V (cm3)	27.2 ± 8.2	19.4 ± 5.5a	19.5 ± 5.7a
T2 (msec)	71.7 ± 5.2	76.0 ± 7.3a	79.4 ± 9.0a,b
FF (%)	38.2 ± 9.7	42.1 ± 10.3a	38.8 ± 13.5b

Note: V volume, FF fat fraction, pre-RT within 2 weeks before radiotherapy, mid-RT 5 weeks after the beginning of radiotherapy, post-RT 4 weeks after radiotherapy. ^a P < 0.017 compared with pre-RT and ^b P < 0.017 compared with mid-RT using paired sample t test with Bonferroni correlation