Code of practice for clinical proton dosimetry

The w-value in air for proton therapy beams

“…Palmans et al (1996) and Seuntjens et al (1994) described water calorimetry and ionization chamber dosimetry in an 85 MeV range-modulated clinical proton beam at a residual energy of 55 MeV. They used the ECHED code of practice (Vynckier et al, 1991 to determine the absorbed doses from ionization chamber measurements. The ratio of the dose measured with the calorimeter to the mean of the doses measured with several different ionization chambers was 0.974.…”

“…The residual proton energy at the measuring depth was 182 MeV. Absorbed doses were calculated from the ionization chamber measurements using the ECHED code of practice (Vynckier et al, 1991). An evaluation of the data reveals that to obtain agreement between calorimetry and ionometry a dry-air (w air ) p -value of (34.170.6) J C À1 is required.…”

“…The residual proton energy at the measuring depth was 180 MeV. Absorbed doses were determined from ionization chamber measurements using the ECHED code of practice (Vynckier et al, 1991 and the AAPM TG-21 protocol (AAPM Task Group 21, 1983). They derived (w air ) p -values for dry air that varied from 34.2 to 34.6 J C À1 using three different ionization chamber calibration techniques.…”

Application of Al 2 O 3 :C+fibre dosimeters for 290 MeV/n carbon therapeutic beam dosimetry

“…In comparison to electron, photon or proton dosimetry, carbon ion dosimetry has to be developed and is currently connected with larger uncertainties [12]. Currently, practiced protocols for clinical proton/HCP dosimetry, such as the AAPM report 16 [13], ECHED code of practice and its supplement [14,15], ICRU report 59 [16] and IAEA TRS-398 [17] recommend cylindrical ionization chambers as reference instruments without taking into account any correction factors for the presence of the ionization chambers in the field. The overall uncertainty in the determination of the absorbed dose in an ion beam is quoted to be 2.8% for cylindrical chambers and 3.2% for plane-parallel chambers.…”

Reference Dosimetry for Fast Neutron and Proton Therapy

“…Several dosimetry protocols for both neutron [1][2][3][4][5][6] and proton [6][7][8][9][10][11] therapy dosimetry have been published. These protocols all recommend that, in the absence of a calorimeter, reference absorbed dose measurements in the clinical situation be made with ionization chambers having 60 Co calibration factors traceable to standards laboratories.…”