Dia 1

- Select the tightest fitting plan -



20 observers

15 RTT’s, 1 PhD student, 4 Physicists



11 patients

- 5 prone with BB, 6 supine



5 CBCT scans per patient



Delineations according to

Roels et al, 2006, IJROPB

3 margins for ventral side upper mesorectum depending on

anatomy captured on CTref:

Rectum

Full

Medium

Empty

Margins

-25 mm, -15 mm, 0 mm -15 mm, 0 mm, 15 mm 0 mm, 15 mm, 25 mm

Design of the study