The linear-quadratic model and fractionated stereotactic radiotherapy
Related Experiment Video
Updated: Aug 30, 2026

Stereotactic Radiosurgery for Gynecologic Cancer
Published on: April 17, 2012
Lizhong Liu1, Daniel A Bassano, Satish C Prasad
1Department of Radiation Oncology, State University of New York, Upstate Medical University, Syracuse, NY 13210, USA. liul@upstate.edu
Purpose:
To determine the dose per fraction that could be used when gamma knife or linear accelerator-based stereotactic treatments are delivered in 2 or more fractions.
Methods And Materials:
The linear-quadratic (LQ) model was used to calculate the dose per fraction for a multiple-fraction regimen which is biologically equivalent to a given single-fraction treatment. The results are summarized in lookup tables.
Results And Conclusion:
The tables can be used by practicing clinicians as a guide in planning fractionated treatment. For the large doses used in typical stereotactic treatments and for small fraction numbers, the model is not very sensitive to the value of the alpha/beta ratio in the LQ model. A simple rule of thumb is found that for two-fraction and three-fraction treatments the dose per fraction is roughly two-thirds and one-half of the single-fraction treatment dose, respectively.
Related Concept Videos
Linear Equations
Linearization and Approximation
Mechanistic Models: Compartment Models in Algorithms for Numerical Problem Solving
In individual population analyses, different algorithms are employed, such as Cauchy's method, which uses a...

