Table 3. Impact of brainstem dose–volume on functional recovery for patients with infratentorial ependymoma treated with postoperative irradiation.

Dose factor	Mean ± SD volume (ml)	Odds ratio (95% CI) of response at 12 months (n = 62 patients)	p value	Odds ratio (95% CI) of response at 24 months (n = 56 patients)	p value
Volume (ml) >54Gy	15.06 + 4.15	1.052 (0.928 to 1.192)	0.43	0.993 (0.877 to 1.125)	0.92
Volume (ml) >56Gy	13.34 + 6.09	1.045 (0.953 to 1.146)	0.35	0.993 (0.912 to 1.082)	0.88
Volume (ml) >58Gy	12.24 + 6.28	1.014 (0.932 to 1.104)	0.75	0.974 (0.897 to 1.058)	0.54
Volume (ml) >60Gy	7.64 + 6.53	1.055 (0.972 to 1.145)	0.2	1.031 (0.949 to 1.120)	0.47
% volume >54Gy	79.95 + 15.66	0.986 (0.954 to 1.020)	0.42	0.964 (0.927 to 1.002)	0.06
% volume >56Gy	69.89 + 28.99	1.002 (0.983 to 1.020)	0.87	0.989 (0.971 to 1.008)	0.25
% volume >58Gy	64.03 + 30.21	0.996 (0.979 to 1.013)	0.64	0.986 (0.969 to 1.004)	0.12
% volume >60Gy	39.60 + 32.47	1.006 (0.989 to 1.022)	0.49	1.001 (0.985 to 1.018)	0.88

Abbreviation: CI = confidence interval.