Dose 2016

Pencil beam kernel parameterisation - 2

Double exponential, incl. depth parameterization, solely based on TPR 20,10 (extracted from photon beam database)

Dose at the centre of a circular field with laterally constant energy fluence in a parallel beam:

d: depth in cm

The pencil kernel is completely defined through 17 parameters that can be calculated using TPR 20,10 (utilizing 6 × 17=102 coefficients).

This parameterization is valid and covers TPR 20,10 from 0.6 up to 0.81 at depths down to 50 cm.

Kernel parameters can be partly interpreted physically

This is the PB kernel parameterization in ESTRO MUV model http://estro-education.org/publications/Documents/EstroBooklet10bw.pdf

T Nyholm, et al (2006) Radiother Oncol 78 , 347-51.