IMRT

DMLC tracking

Overall, the measurements carried out using a 2D ion chamber array agreed well with the gel measurements (Figure 17). However, due to the limited spatial resolution of the 2D array a detailed comparison was not possible. c) Figure 16. Dose distributions measured using gel dosimetry with and without the DMLC-tumour tracking connected. 100 Gel in motion Static gel PTW in motion Static PTW 2D Array in motion tic 2D Array Overall, the measurements carried out using a 2D ion chamber array agreed well with the gel measurements (Figure 17). However, due to the limited spatial resolution of the 2D array a detailed comparison was not possible. 100 Static gel Static PTW Tracked gel Tracked PTW 2D Array in motion Static 2D Array 2D Array c) Figure 16. Dose distributions measured using gel dosimetry with and without the DMLC-tumour tracking connected. a) b) a) b)

This thesis is based on the following papers, hereafter referred to by their roman numerals:

Static gel Static PTW Tracked gel Tracked PTW 2D Array in motion Static 2D Array 2D Array Verification of dynamic radiotherapy: the potential for 3D dosimetry under respiratory-like motion using polymer gel Sofie Ceberg, Anna Karlsson, Helen Gustavsson, Lena Wittgren and Sven Å.J. Bäck Phys. Med. Biol. 53: N387–N396, 2008 -30 -20 -10 0 10 20 30 20 I Dose integration characteristics in normoxic polymer gel dosimetry investigated using sequential beam irradiation Anna Karlsson, Helen Gustavsson*, Sofie Månsson**, Kim B McCauley and Sven Å.J. Bäck Phys. Med. Biol. 52: 4697-4706, 2007 II 40 60 80 Relative absorbed dose [%] Motion extent [mm]

80

60

40

20

-30 -20 -10 0 10 20 30

Motion extent [mm]

Gel in motion Static gel PTW in motion Static PTW 2D Array in motion atic 2D Array b) Figure 17. Relative absorbed dose profiles extracted from nPAG (lines) and 2D ion chamber array (dots) measurement data, performed with the detectors in motion or in a Ceberg et al 80 100 a)

100

80

dose [%]