Article

A study of the effect of the lung shape on the lung absorbed dose in six standard photon and neutron exposure geometries

Physics Department, College of Sciences, Ferdowsi University of Mashhad, 91775-1436 Mashhad, Iran.

^* mirihakim@ferdowsi.um.ac.ir

Received: 19 June 2014
Accepted: 31 October 2014

Abstract

According to the published results of radiation dosimetry studies, there are significant discrepancies in the organ absorbed doses of existing adult male phantoms. As stated, differences in the organ absorbed doses may be associated with the variations in the organs’ volumes, shapes and positions in the body frame. Therefore, this paper focuses on the effect of the lung shape on the lung absorbed dose by creating a series of voxel phantoms, in which the lung shape follows a statistical distribution. These phantoms were exposed to mono-energetic photons and neutrons in six standard irradiation geometries. The results show that when the phantom is irradiated by the low-energy photons, the effects of the lung shape on the lung absorbed dose are considerable (with an uncertainty of more than 100%). For the other irradiation conditions, the variation in the lung shape causes an uncertainty of less than 10% in the dose delivered to the lung.