Ann Radiat Ther Oncol | Volume 1, Issue 2 | Research Article | Open Access

Biophysical Models, Microdosimetry and the Linear Quadratic Survival Relation

Roland B Hawkins*

Department of Radiation Oncology, Ochsner Cancer Institute, Ochsner Medical Center, USA

*Correspondance to: Roland B Hawkins 

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The Linear Quadratic (LQ) survival relation is presented along with its derivation from the Theory of Dual Radiation Action (TDRA) and the related Microdosimetric Kinetic (MK) model. The role of the LQ model in the reporting and interpretation of experimental and clinical studies of the effects of ionizing radiation exposure is discussed. The definition of a Biological Effective Dose (BEDα/β) based on the LQ model is given and its use to compare fractionated radiation treatment courses is described. The implications of heterogeneity of radio sensitivity among the cells of an irradiated cell population with regard to the LQ survival relation and the calculation of the BEDα/β are described. The results of important early studies reported using survival constants defined by the target model are reviewed and related to the survival constants of the LQ survival relation. The dependence of the relative biological effectiveness (RBE) on the linear energy transfer (LET) is presented.


Hawkins RB. Biophysical Models, Microdosimetry and the Linear Quadratic Survival Relation. Ann Radiat Ther Oncol. 2017; 1(2): 1013.

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