Table 2 Comparison of the averaged numerical result of dosimetric metrics from all patients for target coverage and dose to oars between IMPT and proton Arc plans

GTV

D95% [%]

> 100

101.1 ± 1.0

101.4 ± 0.4

0.29

CI_RTOG

1

0.88 ± 0.18

0.96 ± 0.23

0.11

R50% [%]

7.24 ± 2.12

7.25 ± 1.98

0.97

R10% [%]

41.83 ± 13.80

50.71 ± 16.89

0.01

Retina

D_max [Gy]

D_mean [Gy]

< 55

54.5 ± 0.7

37.7 ± 4.9

53.2 ± 0.3

38.0 ± 5.2

< 0.01

0.66

Lens

D_max [Gy]

< 30

22.4 ± 9.2

23.4 ± 8.0

0.42

Cornea

D_max [Gy]

D_mean [Gy]

< 30

24.4 ± 9.1

10.7 ± 5.5

24.0 ± 7.7

10.5 ± 5.4

0.82

0.81

Conjunctiva

D_max [Gy]

D_mean [Gy]

< 55

43.2 ± 7.9

13.6 ± 4.6

44.0 ± 7.5

14.0 ± 5.7

0.30

0.77

Lacrimal Gland

D_max [Gy]

D_mean [Gy]

< 55

41.8 ± 8.6

25.5 ± 12.5

41.9 ± 7.3

24.6 ± 12.2

0.92

0.61

Optic Nerve

D_max [Gy]

D_mean [Gy]

< 55

52.7 ± 1.1

19.6 ± 4.0

52.6 ± 0.6

21.0 ± 4.6

0.86

0.10

Eyebrow

D_max [Gy]

< 20

15.3 ± 7.9

11.7 ± 5.8

0.13