908 / 1195
Number of CT Measurements (k)
1
2
3
4
5
6
7
8
9 10
Max Dose Reduction in CTV (% of Rx Dose)
0
2
4
6
8
10
12
14
16
18
20
22
24
26
28
30
32
34
36
38
Error bars: mean + 1 sd
80% of patients (
p
= 0.08)
95% of patients (
p
= 0.1)
Accumulating Dose with Organ Motion Deformation
• 2% maximum dose reduction:
•initial CT plus 4 suffices for 80% of patients (
p
=0.08)
4-field box
CTV = prostate+SV
similar result for prostate
only